Catastrophic Decompression; Small Place Solo

[Aviation]

I have two questions inspired by Hollywood movies.

In the movies (Goldfinger, Executive Decision and so on),
when pressurized aircraft suffer catastrophic decompression
at high (25000+ feet) altitude (usually when the bad guy
shoots a bullet through a window) everything not tied down
gets sucked out of the plane and the aircraft goes into an
immediate, rapid nose dive and the pilots or the good guys
have to struggle to level it off or prevent a crash.

Is this an automatic "safety" feature of real, regular aircraft?
On the one hand, passengers need to get denser air to breathe
but large aircraft have oxygen masks that drop down. (I could
do some rough estimates that the average fat slob can hold
their breath for less than a minute so, without masks, the jet
would have to go from let's say 30000 feet to 5000 feet in
30-45 seconds. My ears would explode.)

I would think that a crash dive to a lower altitude could be
even more dangerous such as if it occurred in a crowded air
corridor. Maybe there are other dangers.

What REALLY happens (or is supposed to happen) in the event
of sudden decompression of real high flying aircraft?



The second Hollywood inspired question comes from Executive
Decision (1996). The main character is taking flying lessons
in a single prop 2-seater plane and lands. The plane is still
running (on the ground) and his instructor says, 'I think
you're ready to solo' and gets out. The main character starts
to taxi and then other non-flying plot developments happen.
I was wondering if taking your FIRST solo flight is that simple.

The location in the film in Washington, DC but I figure all
US flying is FAA regulated. Wouldn't the first time soloist
have to fill out some forms, file a flight plan with the
airport and maybe even do a complete pre-flight check on the
aircraft? Is the simplified movie solo flight completely
bogus or could it happen that way?


THANK YOU VERY MUCH.






--
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This is a spam protected message. Please answer with reference header.
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[Peter Duniho]

"Aviation" > wrote in message
u...
> I have two questions inspired by Hollywood movies.

One should not believe pretty much anything a Hollywood movie has to say
about anything. Especially aviation.

That said, other than signing the student pilot's certificate and logbook,
there's not much fanfare to the student's first solo.

The other stuff is crap, just like pretty much any other "factual" element
of a Hollywood movie. They are for entertainment, not education.

Pete

[Ron Natalie]

"Aviation" > wrote in message > Is this an automatic "safety" feature of real, regular
aircraft?
> On the one hand, passengers need to get denser air to breathe
> but large aircraft have oxygen masks that drop down.

The pilots initiate the dive for the reasons you suggest. While
supplemental oxygen helps, it's still better to get down to a reasonable
altitude. They presmably notify ATC while they are doing this that
there is an emergency in progress.

>My ears would explode.)

Your ears already exploded when the aircraft cabin went from an
effective altitude of 8000 feet to 36,000 feet in a few seconds when
the depressurization occured.
>
> The second Hollywood inspired question comes from Executive
> Decision (1996). The main character is taking flying lessons
> in a single prop 2-seater plane and lands. The plane is still
> running (on the ground) and his instructor says, 'I think
> you're ready to solo' and gets out. The main character starts
> to taxi and then other non-flying plot developments happen.
> I was wondering if taking your FIRST solo flight is that simple.

That's about how it happens. Technically, the student pilot's certificate
and logbook need to be signed to authorize the solo flight...but that's
pretty much how it happened to me. The instructor figured I was ready,
did a couple of landings with him (without him indicating that I might be
ready for solo) and then he got out. It was at a controlled field, so
shortly after takeoff, the controller asked how much better it flew without
that fat guy in the right seat.

> Wouldn't the first time soloist
> have to fill out some forms, file a flight plan with the
> airport and maybe even do a complete pre-flight check on the
> aircraft?

It wasn't Washington, it was "supposed" to be Frederick, Maryland about 50 miles NW
of DC. No flight plan is required, and the pre-flight check was done before they took off
the first time together, so there isn't much reason to do another.

Of course, most of the rest of that movie, including to stupid diversion to FDK rather than
Dulles (the Dulles runways are much wider and over twice as long as FDK), etc...

[Bob Gardner]

Aircraft pressure vessels are continuously pressurized by bleed air from the
engines...that is, air is being pumped into the plane all of the time. To
keep the airplane from being blown up like a big balloon, an outflow valve
provides a continuous "leak" that lets air escape at a rate programmed by
the cabin altitude setting....so there is already a "hole" in the airplane,
put their by design. I have no direct knowledge of how big an airliner
outflow valve is, but I am going to guess three inches in diameter. Backing
up the outflow valve, in case it sticks in the closed position, is a safety
valve, preloaded to open at a given pressure differential...so there is
another hole, just waiting to open. Contrast that with the hole made by a
9mm bullet.

Don't believe ANYTHING you see on TV or in the movies about aviation. The
producers want viewers to be horrified, so they hype things up quite a bit.
Explosive decompression in and of itself does not cause the airplane to go
out of control, but the emergency measures required to get down to
breathable levels (typically 14,000 feet and below) in a hurry requires
extreme bank angles, far beyond what any airline passenger has ever
experienced in normal flight.

If a window blows out, everything that is not tied down will certainly be
sucked out, and this could include people if they were small enough. I keep
my safety belt fastened at all times when I fly...do you? Pilots have access
to altitude chambers, where they can experience explosive decompression
under controlled conditions...my ears did not blow out during a "dive" from
25000 feet to sea level. There was a big bang and the chamber filled with
fog...that was the moisture from the breath of us "passengers" condensing
out.

Emergency descents are part of training and recurrent training for jet
pilots.

I recall a movie starring either Governor Arnold or Bruce Willis in which a
fuselage-mounted engine was on fire. The hero was hanging out of the door,
of course (conveniently bypassing the fact that they are plug-type doors)
and the smoke from the burning engine was moving forward, into the relative
wind! Quite a trick!

Bob Gardner

"Aviation" > wrote in message
u...
> I have two questions inspired by Hollywood movies.
>
> In the movies (Goldfinger, Executive Decision and so on),
> when pressurized aircraft suffer catastrophic decompression
> at high (25000+ feet) altitude (usually when the bad guy
> shoots a bullet through a window) everything not tied down
> gets sucked out of the plane and the aircraft goes into an
> immediate, rapid nose dive and the pilots or the good guys
> have to struggle to level it off or prevent a crash.
>
> Is this an automatic "safety" feature of real, regular aircraft?
> On the one hand, passengers need to get denser air to breathe
> but large aircraft have oxygen masks that drop down. (I could
> do some rough estimates that the average fat slob can hold
> their breath for less than a minute so, without masks, the jet
> would have to go from let's say 30000 feet to 5000 feet in
> 30-45 seconds. My ears would explode.)
>
> I would think that a crash dive to a lower altitude could be
> even more dangerous such as if it occurred in a crowded air
> corridor. Maybe there are other dangers.
>
> What REALLY happens (or is supposed to happen) in the event
> of sudden decompression of real high flying aircraft?
>
>
>
> The second Hollywood inspired question comes from Executive
> Decision (1996). The main character is taking flying lessons
> in a single prop 2-seater plane and lands. The plane is still
> running (on the ground) and his instructor says, 'I think
> you're ready to solo' and gets out. The main character starts
> to taxi and then other non-flying plot developments happen.
> I was wondering if taking your FIRST solo flight is that simple.
>
> The location in the film in Washington, DC but I figure all
> US flying is FAA regulated. Wouldn't the first time soloist
> have to fill out some forms, file a flight plan with the
> airport and maybe even do a complete pre-flight check on the
> aircraft? Is the simplified movie solo flight completely
> bogus or could it happen that way?
>
>
> THANK YOU VERY MUCH.
>
>
>
>
>
>
> --
> Sent by xanadoof from yahoo element from com
> This is a spam protected message. Please answer with reference header.
> Posted via http://www.usenet-replayer.com

[Ron Natalie]

"Bob Gardner" > wrote in message news:cLmIb.79193$VB2.159840@attbi_s51...
>I have no direct knowledge of how big an airliner
> outflow valve is, but I am going to guess three inches in diameter

I think this is a good guess. It sort of looks like the top of a can of
parmesan cheese.

[Marco Leon]

"Aviation" > wrote in message
u...
>
> The second Hollywood inspired question comes from Executive
> Decision (1996). The main character is taking flying lessons
> in a single prop 2-seater plane and lands. The plane is still
> running (on the ground) and his instructor says, 'I think
> you're ready to solo' and gets out. The main character starts
> to taxi and then other non-flying plot developments happen.
> I was wondering if taking your FIRST solo flight is that simple.
>
> The location in the film in Washington, DC but I figure all
> US flying is FAA regulated. Wouldn't the first time soloist
> have to fill out some forms, file a flight plan with the
> airport and maybe even do a complete pre-flight check on the
> aircraft? Is the simplified movie solo flight completely
> bogus or could it happen that way?
>

Yes as mentioned by others, the first solo is usually that easy (with a
couple of signatures in your logbook)

The plane in Executive Decision was a Bonanza that has 4 or 6 seats (model
F33 or A/B36 respectively. Not sure which was in the movie) and Kurt Russell
is a pilot in real life. That plane could have very well been his own ;) Or
at least he may have been flying it during the filming. Anyone know??

Marco



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[Martin Hotze]

On Tue, 30 Dec 2003 17:32:44 -0500, Ron Natalie wrote:

>I think this is a good guess. It sort of looks like the top of a can of
>parmesan cheese.

A _*can*_ of cheese? Hu?

Cheese has to be 'fresh', and parmesan is made at the table from the piece.

#m

--
harsh regulations in North Korea (read below link after reading the story):
http://www.laweekly.com/ink/04/04/open-mikulan.php
oooops ... sorry ... it happened in the USA, ya know: the land of the free.

[Bob Gardner]

All of the gasses contained in your body come out through the closest
orifice (not your eardrums). Even if you were warned about the impending
decompression, you could not hold your mouth shut. In the pressure chamber,
from 25000 to sea level is instantaneous and you do a sustained
burp-and-fart. Never had to descend at emergency descent rates so I have no
experience in what happens to your breathing on the way down.

Bob Gardner

"Ron Natalie" > wrote in message
m...
>
> "Aviation" > wrote in message > Is
this an automatic "safety" feature of real, regular
> aircraft?
> > On the one hand, passengers need to get denser air to breathe
> > but large aircraft have oxygen masks that drop down.
>
> The pilots initiate the dive for the reasons you suggest. While
> supplemental oxygen helps, it's still better to get down to a reasonable
> altitude. They presmably notify ATC while they are doing this that
> there is an emergency in progress.
>
> >My ears would explode.)
>
> Your ears already exploded when the aircraft cabin went from an
> effective altitude of 8000 feet to 36,000 feet in a few seconds when
> the depressurization occured.
> >
> > The second Hollywood inspired question comes from Executive
> > Decision (1996). The main character is taking flying lessons
> > in a single prop 2-seater plane and lands. The plane is still
> > running (on the ground) and his instructor says, 'I think
> > you're ready to solo' and gets out. The main character starts
> > to taxi and then other non-flying plot developments happen.
> > I was wondering if taking your FIRST solo flight is that simple.
>
> That's about how it happens. Technically, the student pilot's certificate
> and logbook need to be signed to authorize the solo flight...but that's
> pretty much how it happened to me. The instructor figured I was ready,
> did a couple of landings with him (without him indicating that I might be
> ready for solo) and then he got out. It was at a controlled field, so
> shortly after takeoff, the controller asked how much better it flew
without
> that fat guy in the right seat.
>
> > Wouldn't the first time soloist
> > have to fill out some forms, file a flight plan with the
> > airport and maybe even do a complete pre-flight check on the
> > aircraft?
>
> It wasn't Washington, it was "supposed" to be Frederick, Maryland about 50
miles NW
> of DC. No flight plan is required, and the pre-flight check was done
before they took off
> the first time together, so there isn't much reason to do another.
>
> Of course, most of the rest of that movie, including to stupid diversion
to FDK rather than
> Dulles (the Dulles runways are much wider and over twice as long as FDK),
etc...
>

[Bob Gardner]

I just measured my Kraft 8oz container of grated Parmesan...2 3/4 inches.
Close enough?

Bob Gardner

"Ron Natalie" > wrote in message
m...
>
> "Bob Gardner" > wrote in message
news:cLmIb.79193$VB2.159840@attbi_s51...
> >I have no direct knowledge of how big an airliner
> > outflow valve is, but I am going to guess three inches in diameter
>
> I think this is a good guess. It sort of looks like the top of a can of
> parmesan cheese.
>

[Geoffrey Barnes]

Can't offer much help with your first question, but...

> The second Hollywood inspired question comes from Executive
> Decision (1996). The main character is taking flying lessons
> in a single prop 2-seater plane and lands. The plane is still
> running (on the ground) and his instructor says, 'I think
> you're ready to solo' and gets out. The main character starts
> to taxi and then other non-flying plot developments happen.
> I was wondering if taking your FIRST solo flight is that simple.
>
> The location in the film in Washington, DC but I figure all
> US flying is FAA regulated. Wouldn't the first time soloist
> have to fill out some forms, file a flight plan with the
> airport and maybe even do a complete pre-flight check on the
> aircraft? Is the simplified movie solo flight completely
> bogus or could it happen that way?

The basic answer is "more or less". My first solo was more or less exactly
like that. But keep in mind that nobody solos on their first lesson, or
their third, or usually even their fifth, sixth, seventh or eighth. I had
15 sessions of dual instructruction, all with the same instructor, before he
signed me off to do my first solo.

Now, onto specifics. The first time soloist would have to hold a valid
medical certificate, and the instructor is required to have tested the
applicant on key bits of knowledge. Usually, this knowledge is tested using
an informal written examination. But other than getting the medical and
taking this test, no other forms need to be filled out, at least by the
student. The instructor has some paperwork to fill out. Specifically, the
instructor must inscribe some verbage into the student's log book, and sign
off an endorsement on the reverse side of the student's medical certificate.
So the instructor can't just verbally say, "I think you are ready", and then
climb out of the plane. Instead, the student gets a good minute or two to
contemplate their impending solo as the instructor writes things in their
book and on their certificate, and then the instructor gets out. And boy,
is it quiet all of the sudden when the instructor leaves, let me tell you!

No flight plan is required, because the first time soloist isn't really
going anywhere. The most a first time soloist is going to do is take off,
follow a rectangular path around the airport's traffic pattern, and land
(almost always on the same runway that he or she took off from).

The pre-flight wouldn't be necessary in this case, because the characters in
the movie would have alreaedy done one before the lesson began. After the
first few lessons, the student always does a preflight anyway. So in the
movie, the student would have done one prior to taking off with the
instructor onboard. By the way, the instructor has to do a few landings and
takeoffs with the student (I think it's three of each) immediately before
the first solo occurs. I'm not sure if that's part of the FARs, or just a
requirement of my FBO, but that's what he told me.

Hope this helps!

[Kiwi Jet Jock]

> In the pressure chamber,
> from 25000 to sea level is instantaneous and you do a sustained
> burp-and-fart.

> Bob Gardner

Other way around Bob. (sea level to 25,000)

[Mike Rapoport]

The preasure is not going to drop to ambient in an airliner unless there is
a HUGE hole. The combined outflow valve area on an airliner is probably
bigger that the area of a cabin window, maybe several windows. As soon as
the preasure starts dropping, the valves are going to start closing. There
may not even be a loss of preasurization

Mike
MU-2


"G.R. Patterson III" > wrote in message
...
>
>
> Aviation wrote:
> >
> > On the one hand, passengers need to get denser air to breathe
> > but large aircraft have oxygen masks that drop down.
>
> If the aircraft is much above 25,000', the masks will do little good. You
need
> a pressure mask to survive long at (for example) 35,000'. Those used by
the
> airlines for passengers are not good enough for that.
>
> > (I could
> > do some rough estimates that the average fat slob can hold
> > their breath for less than a minute so, without masks, the jet
> > would have to go from let's say 30000 feet to 5000 feet in
> > 30-45 seconds. My ears would explode.)
>
> Nobody can hold their breath in that situation - the pressure difference
will
> cause you to exhale. Above about 25,000', the air pressure is low enough
that
> oxygen actually passes backwards out of your bloodstream into the lungs
and out
> of the body. As for your ears, they're already toast. The pressure just
dropped
> from the pressure at 8,000' to that at cruise altitude in a few seconds.
>
> Basically, the pilots need to get their masks on and get the plane down
below
> 25,000' as rapidly as it can possibly be done. The descent to 10,000' can
be made
> a little more leisurely, but not much - there's always someone in the
cattle
> section who panicked and isn't wearing a mask. If that's one of the flight
> attendants, you're really in trouble.
>
have to do it again just because the instructor's getting out.
>
> George Patterson
> Great discoveries are not announced with "Eureka!". What's usually
said is
> "Hummmmm... That's interesting...."

[Ralph Nesbitt]

"G.R. Patterson III" > wrote in message
...
>
>
> Aviation wrote:
> >
> > On the one hand, passengers need to get denser air to breathe
> > but large aircraft have oxygen masks that drop down.
>
> If the aircraft is much above 25,000', the masks will do little good. You
need
> a pressure mask to survive long at (for example) 35,000'. Those used by
the
> airlines for passengers are not good enough for that.
>
> > (I could
> > do some rough estimates that the average fat slob can hold
> > their breath for less than a minute so, without masks, the jet
> > would have to go from let's say 30000 feet to 5000 feet in
> > 30-45 seconds. My ears would explode.)
>
> Nobody can hold their breath in that situation - the pressure difference
will
> cause you to exhale. Above about 25,000', the air pressure is low enough
that
> oxygen actually passes backwards out of your bloodstream into the lungs
and out
> of the body. As for your ears, they're already toast. The pressure just
dropped
> from the pressure at 8,000' to that at cruise altitude in a few seconds.
>
Agreed
>
> Basically, the pilots need to get their masks on and get the plane down
below
> 25,000' as rapidly as it can possibly be done. The descent to 10,000' can
be made
> a little more leisurely, but not much - there's always someone in the
cattle
> section who panicked and isn't wearing a mask. If that's one of the flight
> attendants, you're really in trouble.
>
Agreed.

There is 1 further issue not yet addressed. Ambient Temp at altitude.
Ambient temps of -30 degrees F or lower are not uncommon at altitudes
>25,000 ASL.

Decompression, explosive or otherwise, results in a significant drop in
cabin Temp resulting in ~ fairly rapid freezing.

There have been any number of documented incidents, military & civilian,
over the years where an A/C lost pressure at altitude, disabling the crew,
with the A/C continuing on "Auto Pilot", crashing when fuel exhausted. It is
routine for A/C in this situation to be intercepted/followed/kept under
surveillance/filmed by military A/C. The most recent "Widely/Highly
Publicized Example"of this was the "Payne Stewart" incident.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Viperdoc]

The FAA has opportunities for a chamber ride to actually experience rapid
decompression, and we have to do it periodically in the Air Force while on
flying status. On of our classmates volunteered to take off his oxygen mask
at 25,000 feet. He turned green immediately and started seizing, and despite
being prepared, he was unable to gang load his oxygen regulator and put his
mask back on. I wonder how many brain cells he killed.

The rapid decompression was pretty uneventful- there was kind of a loud pop,
and a lot of fog. This is the result of condensation due to cooling of the
air from expansion, not moisture from our bodies.

If you ate a lot of Mexican food the night before the pain from the gas
expanding comes on the ascent, not on the descent. Likewise, ear blocks
(feels like sticking an ice pick in your ear from personal experience) comes
during descent only, as the increased ambient pressure pushes inward on your
ear drum.

The most valuable part of the ride was the ability to recognize symptoms of
hypoxia, like decreased color vision, etc. A

Anyone who ever flies over 10,000 feet (or less at night) should consider a
chamber ride a valuable and potentially life saving experience.

[G.R. Patterson III]

Aviation wrote:
>
> On the one hand, passengers need to get denser air to breathe
> but large aircraft have oxygen masks that drop down.

If the aircraft is much above 25,000', the masks will do little good. You need
a pressure mask to survive long at (for example) 35,000'. Those used by the
airlines for passengers are not good enough for that.

> (I could
> do some rough estimates that the average fat slob can hold
> their breath for less than a minute so, without masks, the jet
> would have to go from let's say 30000 feet to 5000 feet in
> 30-45 seconds. My ears would explode.)

Nobody can hold their breath in that situation - the pressure difference will
cause you to exhale. Above about 25,000', the air pressure is low enough that
oxygen actually passes backwards out of your bloodstream into the lungs and out
of the body. As for your ears, they're already toast. The pressure just dropped
from the pressure at 8,000' to that at cruise altitude in a few seconds.

Basically, the pilots need to get their masks on and get the plane down below
25,000' as rapidly as it can possibly be done. The descent to 10,000' can be made
a little more leisurely, but not much - there's always someone in the cattle
section who panicked and isn't wearing a mask. If that's one of the flight
attendants, you're really in trouble.

> I was wondering if taking your FIRST solo flight is that simple.

Pretty much. My instructor also told me to do three takeoffs and landings to a
full stop and park it when I was done.

> The location in the film in Washington, DC but I figure all
> US flying is FAA regulated. Wouldn't the first time soloist
> have to fill out some forms, file a flight plan with the
> airport and maybe even do a complete pre-flight check on the
> aircraft?

All the forms got filled out way back when you applied for a student pilot's
licence. No flight plan is required for any VFR flight in the U.S.. The pre-flight
inspection was done before the student and instructor got in the plane - you
don't have to do it again just because the instructor's getting out.

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

[Jeff Franks]

> If a window blows out, everything that is not tied down will certainly be
> sucked out, and this could include people if they were small enough.

Its my understanding that in an explosive decompression like this, the
decompression will happen very fast. The Goldfinger episode goes on for 45
minutes of hanging on for dear life while the plane depressurizes. My
un-educated guess is that this would happen in seconds or less.

[David G. Nagel]

Get the tail number and look it up...



Marco Leon wrote:
> "Aviation" > wrote in message
> u...
>
>>The second Hollywood inspired question comes from Executive
>>Decision (1996). The main character is taking flying lessons
>>in a single prop 2-seater plane and lands. The plane is still
>>running (on the ground) and his instructor says, 'I think
>>you're ready to solo' and gets out. The main character starts
>>to taxi and then other non-flying plot developments happen.
>>I was wondering if taking your FIRST solo flight is that simple.
>>
>>The location in the film in Washington, DC but I figure all
>>US flying is FAA regulated. Wouldn't the first time soloist
>>have to fill out some forms, file a flight plan with the
>>airport and maybe even do a complete pre-flight check on the
>>aircraft? Is the simplified movie solo flight completely
>>bogus or could it happen that way?
>>
>
>
> Yes as mentioned by others, the first solo is usually that easy (with a
> couple of signatures in your logbook)
>
> The plane in Executive Decision was a Bonanza that has 4 or 6 seats (model
> F33 or A/B36 respectively. Not sure which was in the movie) and Kurt Russell
> is a pilot in real life. That plane could have very well been his own ;) Or
> at least he may have been flying it during the filming. Anyone know??
>
> Marco
>
>
>
> Posted Via Usenet.com Premium Usenet Newsgroup Services
> ----------------------------------------------------------
> ** SPEED ** RETENTION ** COMPLETION ** ANONYMITY **
> ----------------------------------------------------------
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[David G. Nagel]

Having questions about flying in general and soloing in particular I
would like to suggest that everyone go out to your nearest local airport
and inquire into taking the introduction student flight. This is a half
hour flight under instruction and can be free at most FBO's. Check "
http://www.beapilot.com " for information.
The cost of obtaining your private pilot license is in the $3,000 to
$4,000 range. It usually takes 50 to 60 hours of instruction and flying
to qualify.

David Nagel

Geoffrey Barnes wrote:

> Can't offer much help with your first question, but...
>
>
>>The second Hollywood inspired question comes from Executive
>>Decision (1996). The main character is taking flying lessons
>>in a single prop 2-seater plane and lands. The plane is still
>>running (on the ground) and his instructor says, 'I think
>>you're ready to solo' and gets out. The main character starts
>>to taxi and then other non-flying plot developments happen.
>>I was wondering if taking your FIRST solo flight is that simple.
>>
>>The location in the film in Washington, DC but I figure all
>>US flying is FAA regulated. Wouldn't the first time soloist
>>have to fill out some forms, file a flight plan with the
>>airport and maybe even do a complete pre-flight check on the
>>aircraft? Is the simplified movie solo flight completely
>>bogus or could it happen that way?
>
>
> The basic answer is "more or less". My first solo was more or less exactly
> like that. But keep in mind that nobody solos on their first lesson, or
> their third, or usually even their fifth, sixth, seventh or eighth. I had
> 15 sessions of dual instructruction, all with the same instructor, before he
> signed me off to do my first solo.
>
> Now, onto specifics. The first time soloist would have to hold a valid
> medical certificate, and the instructor is required to have tested the
> applicant on key bits of knowledge. Usually, this knowledge is tested using
> an informal written examination. But other than getting the medical and
> taking this test, no other forms need to be filled out, at least by the
> student. The instructor has some paperwork to fill out. Specifically, the
> instructor must inscribe some verbage into the student's log book, and sign
> off an endorsement on the reverse side of the student's medical certificate.
> So the instructor can't just verbally say, "I think you are ready", and then
> climb out of the plane. Instead, the student gets a good minute or two to
> contemplate their impending solo as the instructor writes things in their
> book and on their certificate, and then the instructor gets out. And boy,
> is it quiet all of the sudden when the instructor leaves, let me tell you!
>
> No flight plan is required, because the first time soloist isn't really
> going anywhere. The most a first time soloist is going to do is take off,
> follow a rectangular path around the airport's traffic pattern, and land
> (almost always on the same runway that he or she took off from).
>
> The pre-flight wouldn't be necessary in this case, because the characters in
> the movie would have alreaedy done one before the lesson began. After the
> first few lessons, the student always does a preflight anyway. So in the
> movie, the student would have done one prior to taking off with the
> instructor onboard. By the way, the instructor has to do a few landings and
> takeoffs with the student (I think it's three of each) immediately before
> the first solo occurs. I'm not sure if that's part of the FARs, or just a
> requirement of my FBO, but that's what he told me.
>
> Hope this helps!
>
>

[Hamish Reid]

In article >,
"Ron Natalie" > wrote:

> "Bob Gardner" > wrote in message
> news:cLmIb.79193$VB2.159840@attbi_s51...
> >I have no direct knowledge of how big an airliner
> > outflow valve is, but I am going to guess three inches in diameter
>
> I think this is a good guess. It sort of looks like the top of a can of
> parmesan cheese.

Parmesan cheese comes in *cans*?! Maybe I've lived in the Bay Area too
long :-).

Hamish

[Ralph Nesbitt]

"Jeff Franks" > wrote in message
...
>
> > If a window blows out, everything that is not tied down will certainly
be
> > sucked out, and this could include people if they were small enough.
>
> Its my understanding that in an explosive decompression like this, the
> decompression will happen very fast. The Goldfinger episode goes on for
45
> minutes of hanging on for dear life while the plane depressurizes. My
> un-educated guess is that this would happen in seconds or less.
>
Witnessed the result of "Port Hole Window" on the starboard side of a C-5
blowing out during "Initial Factory Pressure checks" on a new C-5". The
window itself went through the side of a "Tin Sided Building" ~ 200' from
where the window/port hole came from. A substantial number of the
insulation/batting blankets were torn from their normal place in the cargo
bay & piled on the cargo bay floor near the opening. A large number of the
insulation blankets/bats, along with seat cushions from the upper aft troop
compartment were piled around the entrance to the stairs from the troop
compartment down to the cargo bay, plus scattered along the cargo bay floor
in the direction of the failed port hole/window. Seat cushions, mattresses
from bunks, & insulation bats/blankets from the upper front area were piled
against the exit stairs from the upper from lobe & along the cargo bay floor
toward the failed port hole/window. A few of the insulation bats/blankets
were blown out the failed port hole/window.

A/C being tested were instrumented to record/document test protocols as
appropriate. According to instrumentation on the A/C, at time of port
hole/window failure the air pressure dropped from 14.5 lbs to 0 in .003
seconds.

Factory Pressure Check on C-5's was 15 pounds, slightly over 1 atmosphere.
This was worked up to in stages. This incident occurred.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[StellaStar]

>Basically, the pilots need to get their masks on and get the plane down below
>25,000' as rapidly as it can possibly be done.

A couple links to the sad story of Payne Stewart a few years ago. I was
working in Minnesota and there was great consternation as the plane autopiloted
its way across a corner of the state and the military wondered if it would be
necessary to shoot it down. Had it come much closer to a big city, they would
have had to make that decision.

http://www.newsmax.com/articles/?a=1999/10/25/164032

http://www.cnn.com/US/9910/26/shootdown/

The NTSB report:
http://www.ntsb.gov/publictn/2000/AAB0001.htm

I'd always assumed, as many did, that something catastrophic happened shortly
after takeoff, like a window failing, and the pilots didn't even have time to
get oxygen masks on. A friend suggests it never pressurized, which makes one
wonder whether they could become anoxic to the point they were helpless even
without a catastrophe, if they didn't realize the cabin was never
pressurizing...but lots of folks have told me about the foolishness that comes
with lack of oxygen. The full report makes fascinating reading...accident
investigation includes lots and lots of stuff.

[Cub Driver]

>Don't believe ANYTHING you see on TV or in the movies about aviation

In my case, the warning about explosive decompression came from a
BRITISH AIRLINE SECURITY CONSULTANT, speaking on an NPR station. So
clearly the myth extends far beyond Hollywood. This man was presented
as making a living from his special knowledge!


all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[Dr. George O. Bizzigotti]

On Tue, 30 Dec 2003 19:43:55 -0800, "G.R. Patterson III"
> wrote:

>Aviation wrote:

>> On the one hand, passengers need to get denser air to breathe
>> but large aircraft have oxygen masks that drop down.

[snip]

>As for your ears, they're already toast. The pressure just dropped
>from the pressure at 8,000' to that at cruise altitude in a few seconds.

Based on what others have written about chamber simulations, it would
appear that irreversible ear damage (which is what I would infer as
being "toast") is not an inevitable consequence, although. I've no
doubt that the sensation from any reversible consequences is not
always pleasant .

>Basically, the pilots need to get their masks on and get the plane down below
>25,000' as rapidly as it can possibly be done. The descent to 10,000' can be made
>a little more leisurely, but not much - there's always someone in the cattle
>section who panicked and isn't wearing a mask.

One aspect that I have not seen addressed in this thread is the fact
that most oxygen systems can provide supplemental oxygen for a few
minutes only (I dimly recall figures like 3-5 minutes, but that may be
inaccurate). The pilots also need to get down to 10,000 feet within
that time before everyone's oxygen generators run out.

Regards,

George
************************************************** ********************
Dr. George O. Bizzigotti Telephone: (703) 610-2115
Mitretek Systems, Inc. Fax: (703) 610-1558
3150 Fairview Park Drive South E-Mail:
Falls Church, Virginia, 22042-4519
************************************************** ********************

[Marco Leon]

I was hoping this medium would be faster than renting the flick. Besides,
many publically accessible information regarding celebrities are ususally
cryptic. Ever seen a privately-owned plane registered under a corporation?



"David G. Nagel" > wrote in message
...
> Get the tail number and look it up...
>
>
>
> Marco Leon wrote:
> > "Aviation" > wrote in message
> > u...
> >
> >>The second Hollywood inspired question comes from Executive
> >>Decision (1996). The main character is taking flying lessons
> >>in a single prop 2-seater plane and lands. The plane is still
> >>running (on the ground) and his instructor says, 'I think
> >>you're ready to solo' and gets out. The main character starts
> >>to taxi and then other non-flying plot developments happen.
> >>I was wondering if taking your FIRST solo flight is that simple.
> >>
> >>The location in the film in Washington, DC but I figure all
> >>US flying is FAA regulated. Wouldn't the first time soloist
> >>have to fill out some forms, file a flight plan with the
> >>airport and maybe even do a complete pre-flight check on the
> >>aircraft? Is the simplified movie solo flight completely
> >>bogus or could it happen that way?
> >>
> >
> >
> > Yes as mentioned by others, the first solo is usually that easy (with a
> > couple of signatures in your logbook)
> >
> > The plane in Executive Decision was a Bonanza that has 4 or 6 seats
(model
> > F33 or A/B36 respectively. Not sure which was in the movie) and Kurt
Russell
> > is a pilot in real life. That plane could have very well been his own ;)
Or
> > at least he may have been flying it during the filming. Anyone know??
> >
> > Marco
> >
> >
> >
> > Posted Via Usenet.com Premium Usenet Newsgroup Services
> > ----------------------------------------------------------
> > ** SPEED ** RETENTION ** COMPLETION ** ANONYMITY **
> > ----------------------------------------------------------
> > http://www.usenet.com
>



Posted Via Usenet.com Premium Usenet Newsgroup Services
----------------------------------------------------------
** SPEED ** RETENTION ** COMPLETION ** ANONYMITY **
----------------------------------------------------------
http://www.usenet.com

[Ron Natalie]

"Hamish Reid" > wrote in message news:hamishxyz-
> >
> > I think this is a good guess. It sort of looks like the top of a can of
> > parmesan cheese.
>
> Parmesan cheese comes in *cans*?! Maybe I've lived in the Bay Area too
> long :-).
>
Well, the good stuff comes in chunks that you grate yourself. But most of America
eats this Kraft simulation that comes in a shaker can with a little twisty top on it.

[One's Too Many]

"Bob Gardner" > wrote in message news:<d0oIb.79631$VB2.161783@attbi_s51>...
> I just measured my Kraft 8oz container of grated Parmesan...2 3/4 inches.
> Close enough?
>
> Bob Gardner

Well, maybe close enough. That stuff in the Kraft can might qualify as
some kind of 'Parmesan-like substance', but I'd hestiate to call it
real Parmesan cheese. I'd only consider putting it on my pasta if I'd
had way too much wine to drink beforehand.

>
> "Ron Natalie" > wrote in message
> m...
> >
> > "Bob Gardner" > wrote in message
> news:cLmIb.79193$VB2.159840@attbi_s51...
> > >I have no direct knowledge of how big an airliner
> > > outflow valve is, but I am going to guess three inches in diameter
> >
> > I think this is a good guess. It sort of looks like the top of a can of
> > parmesan cheese.
> >

[Ron Natalie]

"One's Too Many" > wrote in message om...
> "Bob Gardner" > wrote in message news:<d0oIb.79631$VB2.161783@attbi_s51>...
> > I just measured my Kraft 8oz container of grated Parmesan...2 3/4 inches.
> > Close enough?
> >
> > Bob Gardner
>
> Well, maybe close enough. That stuff in the Kraft can might qualify as
> some kind of 'Parmesan-like substance', but I'd hestiate to call it
> real Parmesan cheese. I'd only consider putting it on my pasta if I'd
> had way too much wine to drink beforehand.
>

Here's a picture of some outflow valves as well as the pressure relief port that
Bob described. The outflow valve doesn't look like the cheese style one that
I was thinking of:
http://www.b737.org.uk/pressurisation.htm

The cheese one sort of looks like a metal disk with triangles in it that are opened
and closed by rotating the triangles expose the underlying holes in the valve.

By the way, I actually have pictures of LongEZ cockpit vent that was literally the
top of a parmesan cheese can.

[Mike Rapoport]

"Ralph Nesbitt" > wrote in message
m...
>
> "Jeff Franks" > wrote in message
> ...

> Witnessed the result of "Port Hole Window" on the starboard side of a C-5
> blowing out during "Initial Factory Pressure checks" on a new C-5". The
> window itself went through the side of a "Tin Sided Building" ~ 200' from
> where the window/port hole came from. A substantial number of the
> insulation/batting blankets were torn from their normal place in the cargo
> bay & piled on the cargo bay floor near the opening. A large number of the
> insulation blankets/bats, along with seat cushions from the upper aft
troop
> compartment were piled around the entrance to the stairs from the troop
> compartment down to the cargo bay, plus scattered along the cargo bay
floor
> in the direction of the failed port hole/window. Seat cushions, mattresses
> from bunks, & insulation bats/blankets from the upper front area were
piled
> against the exit stairs from the upper from lobe & along the cargo bay
floor
> toward the failed port hole/window. A few of the insulation bats/blankets
> were blown out the failed port hole/window.
>
> A/C being tested were instrumented to record/document test protocols as
> appropriate. According to instrumentation on the A/C, at time of port
> hole/window failure the air pressure dropped from 14.5 lbs to 0 in .003
> seconds.
>
> Factory Pressure Check on C-5's was 15 pounds, slightly over 1 atmosphere.
> This was worked up to in stages. This incident occurred.
> Ralph Nesbitt
> Professional FD/CFR/ARFF Type
>
>
This is not the same situation. First the preasurization was set to twice
what it will be in flight. Second the preasure dropped because the engines
were not pumping air in. Take a bicycle tire pump it up to 8psi (almost
flat) and then let the air out. This it the same preasure differential.

Mike
MU-2

[Jim Weir]

And if you've ever had to service the filter on one of them, you'd gag and vomit
at the next cigarette you saw (back in the '60s, when smoking was all the rage
on the airplane).

There's a hell of a good question -- why did the OUTFLOW valve on the 727
(located on the starboard side of the aircraft back in the aft airstairs
compartment) have a FILTER on it?

Jim


"Ron Natalie" >
shared these priceless pearls of wisdom:

->
->"Bob Gardner" > wrote in message
news:cLmIb.79193$VB2.159840@attbi_s51...
->>I have no direct knowledge of how big an airliner
->> outflow valve is, but I am going to guess three inches in diameter
->
->I think this is a good guess. It sort of looks like the top of a can of
->parmesan cheese.



Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

[Mike Rapoport]

To keep debris from clogging the valve?

Mike
MU-2

"Jim Weir" > wrote in message
...
>
> And if you've ever had to service the filter on one of them, you'd gag and
vomit
> at the next cigarette you saw (back in the '60s, when smoking was all the
rage
> on the airplane).
>
> There's a hell of a good question -- why did the OUTFLOW valve on the 727
> (located on the starboard side of the aircraft back in the aft airstairs
> compartment) have a FILTER on it?
>
> Jim
>
>
> "Ron Natalie" >
> shared these priceless pearls of wisdom:
>
> ->
> ->"Bob Gardner" > wrote in message
> news:cLmIb.79193$VB2.159840@attbi_s51...
> ->>I have no direct knowledge of how big an airliner
> ->> outflow valve is, but I am going to guess three inches in diameter
> ->
> ->I think this is a good guess. It sort of looks like the top of a can of
> ->parmesan cheese.
>
>
>
> Jim Weir (A&P/IA, CFI, & other good alphabet soup)
> VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
> http://www.rst-engr.com

[Ron Natalie]

"Jim Weir" > wrote in message ...

> There's a hell of a good question -- why did the OUTFLOW valve on the 727
> (located on the starboard side of the aircraft back in the aft airstairs
> compartment) have a FILTER on it?

Don't want all that nasty nicotine polluting the upper atmosphere?

Possibly because at ground level, it's possible that air might go in the outflows?

[Scott M. Kozel]

Dr. George O. Bizzigotti > wrote:
>
> "G.R. Patterson III" > wrote:
>
> >Basically, the pilots need to get their masks on and get the plane down below
> >25,000' as rapidly as it can possibly be done. The descent to 10,000' can be made
> >a little more leisurely, but not much - there's always someone in the cattle
> >section who panicked and isn't wearing a mask.
>
> One aspect that I have not seen addressed in this thread is the fact
> that most oxygen systems can provide supplemental oxygen for a few
> minutes only (I dimly recall figures like 3-5 minutes, but that may be
> inaccurate). The pilots also need to get down to 10,000 feet within
> that time before everyone's oxygen generators run out.

How could an SST like the Concorde get from cruising altitude down to
10,000 feet in 3-5 minutes?

[John Gaquin]

"G.R. Patterson III" > wrote in message
>
> If the aircraft is much above 25,000', the masks will do little good. You
need
> a pressure mask to survive long at (for example) 35,000'. Those used by
the
> airlines for passengers are not good enough for that.

Passenger masks generally only need to provide sustenance for a couple of
minutes.

> > ....the jet would have to go from let's say 30000 feet to 5000 feet in
> > 30-45 seconds. My ears would explode.)
>
> Basically, the pilots need to get their masks on and get the plane down
below
> 25,000' as rapidly as it can possibly be done. The descent to 10,000' can
be made
> a little more leisurely, but not much - there's always someone in the
cattle
> section who panicked and isn't wearing a mask. If that's one of the flight
> attendants, you're really in trouble.

Ten thousand is where supplemental O2 is no longer legally required. In
reality, you're back in survivable atmosphere, for most people, at about
14,000 or so. Emergency descent procedures are predicated on descending
from cruise altitude to 10,000 MSL (or an altitude where you can maintain a
cabin alt of 10K) as rapidly as is safely possible. As a practical matter,
you won't be descending at much over 12-15 thousand f/m or so, so the
descent will take a minute and a half or more.

[Robert Moore]

Jim Weir > wrote
> There's a hell of a good question -- why did the OUTFLOW valve on the
> 727 (located on the starboard side of the aircraft back in the aft
> airstairs compartment) have a FILTER on it?

My B-727 Flight Manual does not confirm that this is the location
of the aft outflow valve and with 5 years experience flying the a/c,
(one year as FE) I don't recall it being there.

Bob Moore

[John Gaquin]

"Ron Natalie" > wrote in message news:3ff1fd08$0$32339
>
> "Bob Gardner" > wrote in message news:cLmIb.79193
> >I have no direct knowledge of how big an airliner
> > outflow valve is, but I am going to guess three inches in diameter
>
> I think this is a good guess. It sort of looks like the top of a can of
> parmesan cheese.

Actually, a little bigger. There are two outflow valves that work in
tandem. On the 747 they're located on the aft belly, and each is a touch
smaller in area than one aircraft window -- an oval about 4in by 12in.
There are also two relief valves on the left side of the airplane, and they
are about 8" in diameter.

JG

[Jim Weir]

Different dash models perhaps? PSA had some of the first units to come off the
line. Later models may have found a better location? I dunno. I do remember
changing them at 3 am just after graveyard shift lunchtime. Barfo.

Then again, that was 40+ years ago. Things get hazy when you haven't done them
in a while.

Jim


Robert Moore >
shared these priceless pearls of wisdom:

->Jim Weir > wrote
->> There's a hell of a good question -- why did the OUTFLOW valve on the
->> 727 (located on the starboard side of the aircraft back in the aft
->> airstairs compartment) have a FILTER on it?
->
->My B-727 Flight Manual does not confirm that this is the location
->of the aft outflow valve and with 5 years experience flying the a/c,
->(one year as FE) I don't recall it being there.
->
->Bob Moore


Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

[Mike Rapoport]

Easily. My MU-2 can descend 10,000fpm. Any jet can easily do it.

Mike
MU-2


"Scott M. Kozel" > wrote in message
...
> Dr. George O. Bizzigotti > wrote:
> >
> > "G.R. Patterson III" > wrote:
> >
> > >Basically, the pilots need to get their masks on and get the plane down
below
> > >25,000' as rapidly as it can possibly be done. The descent to 10,000'
can be made
> > >a little more leisurely, but not much - there's always someone in the
cattle
> > >section who panicked and isn't wearing a mask.
> >
> > One aspect that I have not seen addressed in this thread is the fact
> > that most oxygen systems can provide supplemental oxygen for a few
> > minutes only (I dimly recall figures like 3-5 minutes, but that may be
> > inaccurate). The pilots also need to get down to 10,000 feet within
> > that time before everyone's oxygen generators run out.
>
> How could an SST like the Concorde get from cruising altitude down to
> 10,000 feet in 3-5 minutes?

[Ralph Nesbitt]

"Mike Rapoport" > wrote in message
link.net...
>
> "Ralph Nesbitt" > wrote in message
> m...
> >
> > "Jeff Franks" > wrote in message
> > ...
>
> > Witnessed the result of "Port Hole Window" on the starboard side of a
C-5
> > blowing out during "Initial Factory Pressure checks" on a new C-5". The
> > window itself went through the side of a "Tin Sided Building" ~ 200'
from
> > where the window/port hole came from. A substantial number of the
> > insulation/batting blankets were torn from their normal place in the
cargo
> > bay & piled on the cargo bay floor near the opening. A large number of
the
> > insulation blankets/bats, along with seat cushions from the upper aft
> troop
> > compartment were piled around the entrance to the stairs from the troop
> > compartment down to the cargo bay, plus scattered along the cargo bay
> floor
> > in the direction of the failed port hole/window. Seat cushions,
mattresses
> > from bunks, & insulation bats/blankets from the upper front area were
> piled
> > against the exit stairs from the upper from lobe & along the cargo bay
> floor
> > toward the failed port hole/window. A few of the insulation
bats/blankets
> > were blown out the failed port hole/window.
> >
> > A/C being tested were instrumented to record/document test protocols as
> > appropriate. According to instrumentation on the A/C, at time of port
> > hole/window failure the air pressure dropped from 14.5 lbs to 0 in .003
> > seconds.
> >
> > Factory Pressure Check on C-5's was 15 pounds, slightly over 1
atmosphere.
> > This was worked up to in stages. This incident occurred.
> > Ralph Nesbitt
> > Professional FD/CFR/ARFF Type
> >
> >
> This is not the same situation. First the preasurization was set to twice
> what it will be in flight. Second the preasure dropped because the
engines
> were not pumping air in. Take a bicycle tire pump it up to 8psi (almost
> flat) and then let the air out. This it the same preasure differential.
>
> Mike
> MU-2
>
Agreed.

The purpose of the pressure test in question is to assure structural
pressure integrity to 1 atmosphere above AGSL.

Hopefully all realize when referring to "Air Pressure" at altitude this is
an "absolute" pressure value inside the fuselage irrespective of ambient.
When referring to air pressures at ground level the pressure reading is
above unadjusted ambient barometric pressure.

A/C pressure systems are set to operate from departure point. If set
manually from info provided by ATC this is "Unadjusted Barometric Presser"
read from an instrument at the base of the Tower, a specified height above
the ramp. Most modern commercial A/C are equipped with automatic systems
that capture relevant data upon command/that is reset for each flight.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Bob Gardner]

No way. You start off at sea level, of course, and they pump the chamber
pressure down to 25000 feet with masks on...then they do some experiments
with a few of the pilots taking their masks off, just to show how severely
their abilities are affected. Then comes the explosive decompression, which
takes the chamber from 25K back down to sea level in a second or two.

Bob Gardner

"Kiwi Jet Jock" > wrote in message
...
> > In the pressure chamber,
> > from 25000 to sea level is instantaneous and you do a sustained
> > burp-and-fart.
>
> > Bob Gardner
>
> Other way around Bob. (sea level to 25,000)
>
>

[Bob Gardner]

Gotta admit that I am working from memory of events many long years ago and
may easily have screwed up the details. With regard to the fog, however,
there has to be moisture from somewhere...simple expansion is not the whole
story. Fog is, after all, a gazillion eensy-teensy droplets.

Bob

"Viperdoc" > wrote in message
...
> The FAA has opportunities for a chamber ride to actually experience rapid
> decompression, and we have to do it periodically in the Air Force while on
> flying status. On of our classmates volunteered to take off his oxygen
mask
> at 25,000 feet. He turned green immediately and started seizing, and
despite
> being prepared, he was unable to gang load his oxygen regulator and put
his
> mask back on. I wonder how many brain cells he killed.
>
> The rapid decompression was pretty uneventful- there was kind of a loud
pop,
> and a lot of fog. This is the result of condensation due to cooling of the
> air from expansion, not moisture from our bodies.
>
> If you ate a lot of Mexican food the night before the pain from the gas
> expanding comes on the ascent, not on the descent. Likewise, ear blocks
> (feels like sticking an ice pick in your ear from personal experience)
comes
> during descent only, as the increased ambient pressure pushes inward on
your
> ear drum.
>
> The most valuable part of the ride was the ability to recognize symptoms
of
> hypoxia, like decreased color vision, etc. A
>
> Anyone who ever flies over 10,000 feet (or less at night) should consider
a
> chamber ride a valuable and potentially life saving experience.
>
>

[John Gaquin]

I think what Kiwi meant was that you do the "burp & fart" going from SL to
250, when the pressure outside the body is decreasing, as opposed to from
250 to SL, as you posited, when the external pressure would be *increasing*
rapidly.

JG


>
> "Kiwi Jet Jock" > wrote in message
> ...
> > > In the pressure chamber,
> > > from 25000 to sea level is instantaneous and you do a sustained
> > > burp-and-fart.
> >
> > > Bob Gardner
> >
> > Other way around Bob. (sea level to 25,000)
> >
> >
>
> No way. You start off at sea level,

[John Gaquin]

"Bob Gardner" > wrote in message news:JXDIb.16018

> ....With regard to the fog, however,
> there has to be moisture from somewhere...simple expansion is not the
whole
> story.

There is some moisture in the pressurization air pumped into the cabin, but
not much. More is absorbed from the bodies on board and evaporating water
and other fluids. Enough to condense when you rapidly drop the pressure
from around 800 to 300 mb.

JG

[John Gaquin]

"Scott M. Kozel" > wrote in message
>
> How could an SST like the Concorde get from cruising altitude down to
> 10,000 feet in 3-5 minutes?

I'd guess about 3-4 minutes from FL600 to 10K. Just my guess, never read up
on the craft. But 12-15 K ft/m would not be unusual in an emergency
descent.


Regards,

John Gaquin
B727, B747

[Martin Hotze]

On Wed, 31 Dec 2003 10:02:40 -0500, Ron Natalie wrote:

>Well, the good stuff comes in chunks that you grate yourself. But most of America
>eats this Kraft simulation that comes in a shaker can with a little twisty top on it.

*shudder*

#m
--
harsh regulations in North Korea (read below link after reading the story):
http://www.laweekly.com/ink/04/04/open-mikulan.php
oooops ... sorry ... it happened in the USA, ya know: the land of the free.

[Ron Natalie]

"Scott M. Kozel" > wrote in message ...

> How could an SST like the Concorde get from cruising altitude down to
> 10,000 feet in 3-5 minutes?

Push the yoke forward :-)

[Aardvark]

Bob Gardner wrote:
> Then comes the explosive decompression, which
> takes the chamber from 25K back down to sea level in a second or two.
>
> Bob Gardner
>
Just an observation......
Wouldn't the above statement be "implosive compression".

Not trying to stir the pot :)

WW

[Bob Gardner]

Well, it's been awhile, John, and I can hardly remember things that happened
last week, much less things that happened in the 70s. However, I do not
recall anything odd happening to my body during the ascent to 25000 but do
recall my lips doing the blub-blub-blub thing during the decompression. As
the pressure in the chamber rapidly increased, it kinda pushed the trapped
gas out.

Bob

"John Gaquin" > wrote in message
...
> I think what Kiwi meant was that you do the "burp & fart" going from SL to
> 250, when the pressure outside the body is decreasing, as opposed to from
> 250 to SL, as you posited, when the external pressure would be
*increasing*
> rapidly.
>
> JG
>
>
> >
> > "Kiwi Jet Jock" > wrote in message
> > ...
> > > > In the pressure chamber,
> > > > from 25000 to sea level is instantaneous and you do a sustained
> > > > burp-and-fart.
> > >
> > > > Bob Gardner
> > >
> > > Other way around Bob. (sea level to 25,000)
> > >
> > >
> >
> > No way. You start off at sea level,
>
>

[Mike Rapoport]

"Ralph Nesbitt" > wrote in message
m...
> Hopefully all realize when referring to "Air Pressure" at altitude this is
> an "absolute" pressure value inside the fuselage irrespective of ambient.
> When referring to air pressures at ground level the pressure reading is
> above unadjusted ambient barometric pressure.
>
This is incorrect, pressurization is the differential between ambient and
cabin preasure.

Mike
MU-2

> A/C pressure systems are set to operate from departure point. If set
> manually from info provided by ATC this is "Unadjusted Barometric Presser"
> read from an instrument at the base of the Tower, a specified height above
> the ramp. Most modern commercial A/C are equipped with automatic systems
> that capture relevant data upon command/that is reset for each flight.
> Ralph Nesbitt
> Professional FD/CFR/ARFF Type
>
>

[Robert Moore]

"Ralph Nesbitt" wrote
>
> Hopefully all realize when referring to "Air Pressure" at altitude this is
> an "absolute" pressure value inside the fuselage irrespective of ambient.
> When referring to air pressures at ground level the pressure reading is
> above unadjusted ambient barometric pressure.

In the Boeing aircraft that I flew (B-727,B-707,B-720) there were two
gages on the FE's panel. One was a simple altimeter that indicated the
cabin altitude at all times and the other, a differential pressure gage
that indicated the difference in pressure between outside and inside.
The maximum differential for those aircraft was around 8.6 psi. The only
way to determine the absolute pressure inside the aircraft would be to use
a graph to convert the altimeter indication to pressure.

Bob Moore

[G.R. Patterson III]

Jim Weir wrote:
>
> There's a hell of a good question -- why did the OUTFLOW valve on the 727
> (located on the starboard side of the aircraft back in the aft airstairs
> compartment) have a FILTER on it?

Obviously to protect the people on the ground from the effects of secondary smoke.

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

[Jon Woellhaf]

During the explosive decompression portion of my Air Force altitude chamber
training, we sat in a small chamber adjacent to the larger main chamber with
our masks off. The airtight door between the two chambers was closed. The
large chamber was evacuated to 50,000 feet, or so. We were at about 10,000
feet and had our masks off.

Without warning, the hatch between the chambers was suddenly opened. There
was a loud bang, and the pressure in the two chambers very quickly equalized
to about 30,000 feet. The whole chamber filled with thick fog. I felt for my
mask and put it on.

Ever after, I have been amused at the flight attendant's briefing, "In the
unlikely event of a sudden loss of cabin pressure, the oxygen masks in front
of you will automatically deploy. Simply put the mask over your mouth and
nose and breath normally. Etc. etc."

Yeah, right! First there's a loud bang and everyone thinks a bomb has gone
off. Then the cabin fills with super cold thick fog. The pilot puts the
plane in a dive to get to breathable air and the masks are hanging a couple
feet in front of you. I think it would be absolute chaos.

Have any of you experienced an actual explosive decompression while in
flight?

Jon

[John Galban]

Cub Driver > wrote in message >...
> >Don't believe ANYTHING you see on TV or in the movies about aviation
>
> In my case, the warning about explosive decompression came from a
> BRITISH AIRLINE SECURITY CONSULTANT, speaking on an NPR station. So
> clearly the myth extends far beyond Hollywood. This man was presented
> as making a living from his special knowledge!
>

Was that in reference to a stray bullet causing the decompression?
If so, I'd have to agree that he's full of it. Explosive
decompression caused by a larger hole in the pressure vessel (i.e.
small bomb or failure of the structure) can be quite serious.
Remember that 747 that had a big chunk of the skin blow out enroute to
Australia? As I recall, 2 or 3 people were sucked out along with
their seats. Also, at 35K ft. the amount of time until loss of
conciousness is measured in seconds.

I was once enroute on a long X-C near the AZ/NM border when I heard
a TWA flight tell Center that they were in an emergency descent due to
a sudden decompression of the cabin. A few minutes later I watched
the 727 come down to 12K ft. (a few thousand ft. over the mountain
tops) and start a turn east towards Albuquerque. Very strange to see
something that large down at unpressurized GA altitudes.

John Galban=====>N4BQ (PA28-180)

[Robert Moore]

"Bob Gardner" > wrote
> No way. You start off at sea level, of course, and they pump the chamber
> pressure down to 25000 feet with masks on...then they do some experiments
> with a few of the pilots taking their masks off, just to show how severely
> their abilities are affected. Then comes the explosive decompression, which
> takes the chamber from 25K back down to sea level in a second or two.

Bob, what you have described is "explosive compression" not "decompression".

I would reccommend this web site to clear-up the confusion:

http://www.wvi.com/~lelandh/Alt_Chamber.htm

Bob Moore

[Scott M. Kozel]

(John Galban) wrote:
>
> Was that in reference to a stray bullet causing the decompression?
> If so, I'd have to agree that he's full of it. Explosive
> decompression caused by a larger hole in the pressure vessel (i.e.
> small bomb or failure of the structure) can be quite serious.
> Remember that 747 that had a big chunk of the skin blow out enroute to
> Australia? As I recall, 2 or 3 people were sucked out along with
> their seats. Also, at 35K ft. the amount of time until loss of
> conciousness is measured in seconds.

About 22,000 feet, and 9 pax were sucked out. Better than the loss of
all 356 people on board, though.

Date: February 24, 1989
Type: 747-122
Registration: N4713U
Operator: United Airlines
Where: Honolulu, Hawaii
Report No. NTSB-AAR-90-01
Report Date: April 16, 1990 Pages: 68

Executive Summary:

On February 24, 1989, United Airlines (UAL), flight 811, a Boeing
747-122 (B-747), N4713U, was being operated as a regularly scheduled
flight from Los Angeles, California (LAX) to Sydney, Australia (SYD)
with intermediate stops in Honolulu, Hawaii (HNL) and Aukland, New
Zealand (AKL). There were 3 flightcrew, 15 flight attendants, and 337
passengers aboard the airplane.

The flightcrew reported the airplane's operation to be normal during
the takeoff from Honolulu, and during the initial and intermediate
segments of the climb. The flightcrew observed en route thunderstorms
both visually and on the airplane's weather radar, so they requested
and received clearance for a deviation to the left of course from the
HNL Combined Center Radar Approach Control (CERAP). The captain
elected to leave the passenger seat belt sign "on."

The flightcrew stated that the first indication of a problem occurred
while the airplane was climbing between 22,000 and 23,000 feet at an
indicated airspeed (IAS) of 300 knots. They heard a sound, described
as a "thump," which shook the airplane. They said that this sound was
followed immediately by a "tremendous explosion." The airplane had
experienced an explosive decompression. They said that they donned
their respective oxygen masks but found no oxygen available. Engines
No. 3 and 4 were shutdown because of damage from foreign object
ingestion.

The airplane made a successful emergency landing at HNL and the
occupants evacuated the airplane. Examination of the airplane revealed
that the forward lower lobe cargo door had separated in flight and had
caused extensive damage to the fuselage and cabin structure adjacent to
the door. Nine of the passengers had been ejected from the airplane
and lost at sea.

The issues in this investigation centered around the design and
certification of the B-747 cargo doors, and the operation and
maintenance to assure the continuing airworthiness of the doors.

The National Transportation Safety Board determines that the probable
cause of this accident was the sudden opening of the improperly latched
forward lower lobe cargo door in flight and the subsequent explosive
decompression. Contributing to the cause of the accident was a
deficiency in the design of the cargo door locking mechanisms, which
made them susceptible to inservice damage, and which allowed the door
to be unlatched, yet to show a properly latched and locked position.
Also contributing to the accident was the lack of proper maintenance
and inspection of the cargo door by United Airlines, and a lack of
timely corrective actions by Boeing and the FAA following the 1987
cargo door opening incident on a Pan Am B-747.

The Safety Board issued three safety recommendations as a result of
this investigation that addressed measures to improve the airworthiness
of the B-747 cargo doors and other non-plug doors on pressurized
transport category airplanes. It also issued recommendations affecting
cabin safety.

http://dnausers.d-n-a.net/dnetGOjg/240289.htm

--
Scott M. Kozel Highway and Transportation History Websites
Virginia/Maryland/Washington, D.C. http://www.roadstothefuture.com
Philadelphia and Delaware Valley http://www.pennways.com

[Rob Perkins]

On Tue, 30 Dec 2003 23:05:40 GMT, Martin Hotze >
wrote:

>On Tue, 30 Dec 2003 17:32:44 -0500, Ron Natalie wrote:
>
>>I think this is a good guess. It sort of looks like the top of a can of
>>parmesan cheese.
>
>A _*can*_ of cheese? Hu?
>
>Cheese has to be 'fresh', and parmesan is made at the table from the piece.

You *can't* have spent enough time in the U.S. if you've never seen a
green can of Kraft grated parmesan cheese.

And there's no such thing as "fresh cheese".

Rob

[Jim Weir]

Then you've never been around Oshkosh at dawn after a couple of six-packs and a
few cans of bean dip the night before.

Jim

->
->And there's no such thing as "fresh cheese".
->
->Rob


Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

[Bob Gardner]

Wouldn't it be nice if all participants in the aviation newsgroups
subscribed to...what was that name again?...oh yes, the Summit Aviation
CD-ROM. Then they could research this stuff themselves.

(Couldn't live without it, Jon)

Bob Gardner

"Jon Woellhaf" > wrote in message
news:jvFIb.85543$VB2.191432@attbi_s51...
> During the explosive decompression portion of my Air Force altitude
chamber
> training, we sat in a small chamber adjacent to the larger main chamber
with
> our masks off. The airtight door between the two chambers was closed. The
> large chamber was evacuated to 50,000 feet, or so. We were at about 10,000
> feet and had our masks off.
>
> Without warning, the hatch between the chambers was suddenly opened. There
> was a loud bang, and the pressure in the two chambers very quickly
equalized
> to about 30,000 feet. The whole chamber filled with thick fog. I felt for
my
> mask and put it on.
>
> Ever after, I have been amused at the flight attendant's briefing, "In the
> unlikely event of a sudden loss of cabin pressure, the oxygen masks in
front
> of you will automatically deploy. Simply put the mask over your mouth and
> nose and breath normally. Etc. etc."
>
> Yeah, right! First there's a loud bang and everyone thinks a bomb has gone
> off. Then the cabin fills with super cold thick fog. The pilot puts the
> plane in a dive to get to breathable air and the masks are hanging a
couple
> feet in front of you. I think it would be absolute chaos.
>
> Have any of you experienced an actual explosive decompression while in
> flight?
>
> Jon
>
>

[Aviation]

Thank you, everyone, for providing lots of helpful answers and info.

Even with slightly inaccurate info (2-seater; 6-seater), I guess
the second Q was easy:
>>Is the simplified movie solo flight completely
>> bogus or could it happen that way?
>
>The basic answer is "more or less".

The answers to the first Q, being more tecnically compicated, leave
me asking for a few clarifications. That was about what REALLY happens
when a large pressurized aircraft, e.g., a 747, explosively or
catastrophically decompresses at high (25000+ feet) altitude.

Ron Natalie ) wrote:
>> On the one hand, passengers need to get denser air to breathe
>> but large aircraft have oxygen masks that drop down.
>
>The pilots initiate the dive for the reasons you suggest. While
>supplemental oxygen helps, it's still better to get down to a >reasonable altitude. They presmably notify ATC while they are doing
>this that there is an emergency in progress.

So, other than alarms or other signals, there is NOTHING AUTOMATIC
that puts the aircraft into rapid descent. Pilots have to respond
to the signals (explosion, screams from the cabin, meters in their
cockpit, their own ears popping, flashing lights, bells and whistles,
etc.) and initiate the dive MANUALLY. For well trained pilots this
would take, what, only a few seconds at most? Do they put their oxygen
masks on FIRST or start the dive first?

In some movies, the pilots are often unconscious, slumped over the
controls (wedging the 'steering wheel' / joystick full forward) as
the hero struggles to pull them out of the way and get out of the
dive. It sounds like a pilot, if not alert or in good health, could
actually lose consciousness from hypoxia under these conditions, so
maybe those kinds of movie scenes are ALMOST believable?

(This assumes worst case total decompression. It was pointed out
by Mike Rapoport ) that the cabin might
not even go to ambient pressure if the hole isn't too big and the
outflow valves close down and the engines keep pumping air into the
cabin.)

Someone also pointed out my goof about "holding" your breath
upon going from cabin (8000 ft pressure) to ambient (25-35,000
ft pressure). In estimating how much time the average civilian
passenger could go without TAKING a breath of good air (14,000
ft or below), I used the HOLD your breath estimate. Assuming
there is 3-5 minutes of mask-oxygen and one minute of "holding"
the last breath, they've got 3-6 minutes to get down to breathable
(14,000 ft?) air and then below. For the movie Executive Decision,
they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?

I found some rate of ASCENT data of about 3850 ft/min at
http://www.altairva-fs.com/fleet/poh/Boeing%20747%20POH.htm
but descent data isn't clear to me but it looks like 2500 ft/min
from cruise altitude down to 10,000 ft is the recommended ROD.

The discussion of the ear problem seems unsettled. Upon going
from 8000 ft cabin pressure to 25000+ ft pressure in a couple
of seconds (if loss of pressure is total), some rapid swallowing
should equilibrate your ears to low pressure. Descending from
25,000+ (39,000) ft at 5,000 ft/min could result in reversible
or IRREVERSIBLE damage depending on a person's ability to
equilibrate REALLY fast. Apparently, some people posting have
done this during training in hyperbaric chambers.

Once again, THANK YOU for your answers. Even tho' I'm annoyed
or perplexed by a lot of Hollywood pseudoscience, I get extra
value from these usenet discussions.

Have a Happy New Year.






--
Sent by xanadoof from yahoo included in com
This is a spam protected message. Please answer with reference header.
Posted via http://www.usenet-replayer.com

[Ron Natalie]

"Bob Gardner" > wrote in message news:bgFIb.16418$I07.44872@attbi_s53...
> Well, it's been awhile, John, and I can hardly remember things that happened
> last week, much less things that happened in the 70s. However, I do not
> recall anything odd happening to my body during the ascent to 25000 but do
> recall my lips doing the blub-blub-blub thing during the decompression. As
> the pressure in the chamber rapidly increased, it kinda pushed the trapped
> gas out.
It's the other parts of your body doing the blub-blub-blub thing that's problematic.

[Mike Rapoport]

Basically the Hollywood depicts what would happen if the cabin was
preasurized to 400PSI.

Mike
MU-2

"Aviation" > wrote in message
u...
> Thank you, everyone, for providing lots of helpful answers and info.
>
> Even with slightly inaccurate info (2-seater; 6-seater), I guess
> the second Q was easy:
> >>Is the simplified movie solo flight completely
> >> bogus or could it happen that way?
> >
> >The basic answer is "more or less".
>
> The answers to the first Q, being more tecnically compicated, leave
> me asking for a few clarifications. That was about what REALLY happens
> when a large pressurized aircraft, e.g., a 747, explosively or
> catastrophically decompresses at high (25000+ feet) altitude.
>
> Ron Natalie ) wrote:
> >> On the one hand, passengers need to get denser air to breathe
> >> but large aircraft have oxygen masks that drop down.
> >
> >The pilots initiate the dive for the reasons you suggest. While
> >supplemental oxygen helps, it's still better to get down to a >reasonable
altitude. They presmably notify ATC while they are doing
> >this that there is an emergency in progress.
>
> So, other than alarms or other signals, there is NOTHING AUTOMATIC
> that puts the aircraft into rapid descent. Pilots have to respond
> to the signals (explosion, screams from the cabin, meters in their
> cockpit, their own ears popping, flashing lights, bells and whistles,
> etc.) and initiate the dive MANUALLY. For well trained pilots this
> would take, what, only a few seconds at most? Do they put their oxygen
> masks on FIRST or start the dive first?
>
> In some movies, the pilots are often unconscious, slumped over the
> controls (wedging the 'steering wheel' / joystick full forward) as
> the hero struggles to pull them out of the way and get out of the
> dive. It sounds like a pilot, if not alert or in good health, could
> actually lose consciousness from hypoxia under these conditions, so
> maybe those kinds of movie scenes are ALMOST believable?
>
> (This assumes worst case total decompression. It was pointed out
> by Mike Rapoport ) that the cabin might
> not even go to ambient pressure if the hole isn't too big and the
> outflow valves close down and the engines keep pumping air into the
> cabin.)
>
> Someone also pointed out my goof about "holding" your breath
> upon going from cabin (8000 ft pressure) to ambient (25-35,000
> ft pressure). In estimating how much time the average civilian
> passenger could go without TAKING a breath of good air (14,000
> ft or below), I used the HOLD your breath estimate. Assuming
> there is 3-5 minutes of mask-oxygen and one minute of "holding"
> the last breath, they've got 3-6 minutes to get down to breathable
> (14,000 ft?) air and then below. For the movie Executive Decision,
> they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
> to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?
>
> I found some rate of ASCENT data of about 3850 ft/min at
> http://www.altairva-fs.com/fleet/poh/Boeing%20747%20POH.htm
> but descent data isn't clear to me but it looks like 2500 ft/min
> from cruise altitude down to 10,000 ft is the recommended ROD.
>
> The discussion of the ear problem seems unsettled. Upon going
> from 8000 ft cabin pressure to 25000+ ft pressure in a couple
> of seconds (if loss of pressure is total), some rapid swallowing
> should equilibrate your ears to low pressure. Descending from
> 25,000+ (39,000) ft at 5,000 ft/min could result in reversible
> or IRREVERSIBLE damage depending on a person's ability to
> equilibrate REALLY fast. Apparently, some people posting have
> done this during training in hyperbaric chambers.
>
> Once again, THANK YOU for your answers. Even tho' I'm annoyed
> or perplexed by a lot of Hollywood pseudoscience, I get extra
> value from these usenet discussions.
>
> Have a Happy New Year.
>
>
>
>
>
>
> --
> Sent by xanadoof from yahoo included in com
> This is a spam protected message. Please answer with reference header.
> Posted via http://www.usenet-replayer.com

[Ron Natalie]

"Jim Weir" > wrote in message ...
>
> Then you've never been around Oshkosh at dawn after a couple of six-packs and a
> few cans of bean dip the night before.
>
Don't forget the cheese curds!

[G.R. Patterson III]

Bob Gardner wrote:
>
> Gotta admit that I am working from memory of events many long years ago and
> may easily have screwed up the details. With regard to the fog, however,
> there has to be moisture from somewhere...simple expansion is not the whole
> story. Fog is, after all, a gazillion eensy-teensy droplets.

When the pressure drops, the temperature drops. All that happened was you went
below the dew point in the chamber.

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

[Ron Natalie]

"Aviation" > wrote in message >
> For well trained pilots this
> would take, what, only a few seconds at most? Do they put their oxygen
> masks on FIRST or start the dive first?

At the most. They almost certainly put their maskes on first, but they are
of a "quick don" type that can be put on with one hand, so it's quite concievable
that they are already starting the dive concurrently with flipping the mask over
their face.

> In some movies, the pilots are often unconscious, slumped over the
> controls (wedging the 'steering wheel' / joystick full forward) as
> the hero struggles to pull them out of the way and get out of the
> dive. It sounds like a pilot, if not alert or in good health, could
> actually lose consciousness from hypoxia under these conditions, so
> maybe those kinds of movie scenes are ALMOST believable?

I believe that you've got a reasonable amount of time (30 seconds).
I can't vounch for whatever scenario you're specifically talking about.

> For the movie Executive Decision,
> they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
> to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?

5000 feet a minute isn't hard to obtain.

[John Gaquin]

"Aviation" > wrote in message
>
> So, other than alarms or other signals, there is NOTHING AUTOMATIC
> that puts the aircraft into rapid descent.

Correct.


>Pilots have to respond to the signals... and initiate the dive MANUALLY.
For well >trained pilots this would take, what, only a few seconds at most?
Do they put their >oxygen masks on FIRST or start the dive first?

*Always* get the cockpit crew on O2 before anything else.

>
> In some movies, the pilots are often unconscious, slumped over the
> controls (wedging the 'steering wheel' / joystick full forward) as
> the hero struggles to pull them out of the way and get out of the
> dive. It sounds like a pilot, if not alert or in good health, could
> actually lose consciousness from hypoxia under these conditions, so
> maybe those kinds of movie scenes are ALMOST believable?

Not even remotly close to almost believable. Hollywood would have you
believe that there is an auto-trigger on all aircraft that renders the
engines non-functional, the aircraft uncontrollable, and the crew
unconscious whenever anything stressful occurs in the passenger cabin.
Truth is, if you're cruising at FL350 or higher you've only got about 5
seconds max to get the mask on, but it only takes about one to two seconds
to don the mask and get full O2 flowing. This is why crews train to an
instinctive reaction to get the mask FIRST. A person in average good health
will not have a problem with a few seconds of decompressing atmosphere. The
problem comes in on long flights. Toward the end, your day is already 12 or
more hours long, you're up high for efficiency - maybe 390 or 410 - which
means the cabin altitude is up around 9000 ft or more and everyone is tired.
Reaction time becomes crucial. When you're cruising high, a prudent crew
will ensure that the masks are preset and ready to go, and will don the O2
for a few minutes every little while just to make sure everyone stays alert.



> Assuming
> there is 3-5 minutes of mask-oxygen and one minute of "holding"
> the last breath, they've got 3-6 minutes to get down to breathable
> (14,000 ft?) air and then below. For the movie Executive Decision,
> they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
> to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?

Absolutely. In an emergency descent, the prime (only) consideration is to
*get down safely*. The limiting factor is airspeed buildup. Airplanes are
very "slippery", and will build up speed at an impressive rate when allowed
to run freely downhill. In a rapid descent, you extend all the high drag
devices you can use (flaps, slats, spoilers, Ldg gear) to control airspeed
while you let the craft descend at the maximum vertical rate possible. In
the 747, the limit airspeed is 320 kt, (iirc) and that speed range's not
atypical for other transports, either. Typically, you'll see descent rates
of 10 to 15 thousand feet/minute.


>
> The discussion of the ear problem seems unsettled..... Descending from
> 25,000+ (39,000) ft at 5,000 ft/min could result in reversible
> or IRREVERSIBLE damage depending on a person's ability to
> equilibrate REALLY fast.

When you get into emergency actions, you think in terms of minimizing or
prioritizing injuries. A rapid descent may well cause some passengers (or
crew) ear injuries, or even broken bones if they're not belted in. But the
alternative is substantially less desirable.

[Bob Gardner]

Read 91.211 for more info. There are conditions under which one pilot must
be wearing the mask under non-emergency conditions.

This reminds me of the time when LearJet got a jet certified for 51,000
feet...the photograph in the aviation press showed both pilots smiling into
the camera at FL510 without an oxygen mask in sight. Always wondered how the
FAA reacted to that.

Bob Gardner

"Aviation" > wrote in message
u...
> Thank you, everyone, for providing lots of helpful answers and info.
>
> Even with slightly inaccurate info (2-seater; 6-seater), I guess
> the second Q was easy:
> >>Is the simplified movie solo flight completely
> >> bogus or could it happen that way?
> >
> >The basic answer is "more or less".
>
> The answers to the first Q, being more tecnically compicated, leave
> me asking for a few clarifications. That was about what REALLY happens
> when a large pressurized aircraft, e.g., a 747, explosively or
> catastrophically decompresses at high (25000+ feet) altitude.
>
> Ron Natalie ) wrote:
> >> On the one hand, passengers need to get denser air to breathe
> >> but large aircraft have oxygen masks that drop down.
> >
> >The pilots initiate the dive for the reasons you suggest. While
> >supplemental oxygen helps, it's still better to get down to a >reasonable
altitude. They presmably notify ATC while they are doing
> >this that there is an emergency in progress.
>
> So, other than alarms or other signals, there is NOTHING AUTOMATIC
> that puts the aircraft into rapid descent. Pilots have to respond
> to the signals (explosion, screams from the cabin, meters in their
> cockpit, their own ears popping, flashing lights, bells and whistles,
> etc.) and initiate the dive MANUALLY. For well trained pilots this
> would take, what, only a few seconds at most? Do they put their oxygen
> masks on FIRST or start the dive first?
>
> In some movies, the pilots are often unconscious, slumped over the
> controls (wedging the 'steering wheel' / joystick full forward) as
> the hero struggles to pull them out of the way and get out of the
> dive. It sounds like a pilot, if not alert or in good health, could
> actually lose consciousness from hypoxia under these conditions, so
> maybe those kinds of movie scenes are ALMOST believable?
>
> (This assumes worst case total decompression. It was pointed out
> by Mike Rapoport ) that the cabin might
> not even go to ambient pressure if the hole isn't too big and the
> outflow valves close down and the engines keep pumping air into the
> cabin.)
>
> Someone also pointed out my goof about "holding" your breath
> upon going from cabin (8000 ft pressure) to ambient (25-35,000
> ft pressure). In estimating how much time the average civilian
> passenger could go without TAKING a breath of good air (14,000
> ft or below), I used the HOLD your breath estimate. Assuming
> there is 3-5 minutes of mask-oxygen and one minute of "holding"
> the last breath, they've got 3-6 minutes to get down to breathable
> (14,000 ft?) air and then below. For the movie Executive Decision,
> they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
> to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?
>
> I found some rate of ASCENT data of about 3850 ft/min at
> http://www.altairva-fs.com/fleet/poh/Boeing%20747%20POH.htm
> but descent data isn't clear to me but it looks like 2500 ft/min
> from cruise altitude down to 10,000 ft is the recommended ROD.
>
> The discussion of the ear problem seems unsettled. Upon going
> from 8000 ft cabin pressure to 25000+ ft pressure in a couple
> of seconds (if loss of pressure is total), some rapid swallowing
> should equilibrate your ears to low pressure. Descending from
> 25,000+ (39,000) ft at 5,000 ft/min could result in reversible
> or IRREVERSIBLE damage depending on a person's ability to
> equilibrate REALLY fast. Apparently, some people posting have
> done this during training in hyperbaric chambers.
>
> Once again, THANK YOU for your answers. Even tho' I'm annoyed
> or perplexed by a lot of Hollywood pseudoscience, I get extra
> value from these usenet discussions.
>
> Have a Happy New Year.
>
>
>
>
>
>
> --
> Sent by xanadoof from yahoo included in com
> This is a spam protected message. Please answer with reference header.
> Posted via http://www.usenet-replayer.com

[Robert Moore]

"John Gaquin" > wrote
> Truth is, if you're cruising at FL350 or higher you've only got about 5
> seconds max to get the mask on, but it only takes about one to two
> seconds to don the mask and get full O2 flowing.

From the following web site:

http://www.sff.net/people/Geoffrey.Landis/vacuum.html

A larger body of information about how long you would remain conscious comes
from aviation medicine. Aviation medicine defines the "time of useful
consciousness", that is, how long after a decompression incident pilots will
be awake and be sufficiently aware to take active measures to save their
lives. Above 40,000 feet (12 km), the time of useful consciousness is 12 to
25 seconds. (The shorter figure is for a person actively moving; the longer
figure is for a person sitting quietly.)

The number that we were always taught in the airline business was that at
39,000', the time of useful conciousness was 18 seconds.

Bob Moore

[Robert Moore]

"Bob Gardner" > wrote

> This reminds me of the time when LearJet got a jet certified for 51,000
> feet...the photograph in the aviation press showed both pilots smiling
> into the camera at FL510 without an oxygen mask in sight. Always
> wondered how the FAA reacted to that.

They probably had "quick donners" available, which modifies the reg.

Bob Moore

[Jim Weir]

Yes, I got results on the carbon fiber and I would have SWORN that I posted them
to this site.

Putting a GPS antenna UNDER a small bowl-shaped carbon fiber radome immediately
killed any GPS signal into a 27 dB gain active antenna INCLUDING satellites that
were directly overhead.

Figuring that the carbon was so lousy a transmissive path, I drilled a hole on
the top of the bowl and used the bowl as the groundplane. VIOLA. The GPS
antenna worked every bit as well on TOP of the carbon fiber as it did on a metal
ground plane of approximately the same size.

I can't say this is true for any other service than GPS (transponder, vhf nav &
com, etc.) but it did test well for GPS.

Jim



Richard Riley >
shared these priceless pearls of wisdom:

->
->Did you ever get results on the carbon?

Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

[Cub Driver]

> Was that in reference to a stray bullet causing the decompression?
>If so, I'd have to agree that he's full of it.

Yes, just so. He agreed that the sky marshal would have frangible
bullets, but argued that the terrorist would not. That would lead to a
bullet through the airplane (he didn't specify window, which I
understand to be a problem) followed by explosive decompression "and
all that that entails."

all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

[John Gaquin]

"Robert Moore" > wrote in message
>
> Above 40,000 feet (12 km), the time of useful consciousness is 12 to
> 25 seconds. (The shorter figure is for a person actively moving; the
longer
> figure is for a person sitting quietly.)
>
> The number that we were always taught in the airline business was that at
> 39,000', the time of useful conciousness was 18 seconds.

Bob, I was taught similar numbers. I based my estimate solely on anecdotal
reference provided by two friends, each of whom had "enjoyed" a rapid
decompression at high flight level -- one at 390 and one at 410. The fellow
at 390 was out of his seat getting coffee (small galley immediately behind
the jump seats on 747 freighters) when the cabin blew. They both related
similar sensations. They went right for the masks, and had them on quickly
[estimated 2-3 seconds for the guy in his seat, and 3-4 seconds for the
coffee drinker], but each said they felt "spacey" almost immediately. A
combination of fatigue, confusion, forced exhalation, etc., left each of
them, in separate instances, with the conviction that at somewhere around 10
seconds or so they probably would have lost the mental discipline to stay
focused and get the damn mask on. I have no personal experience that would
allow me to comment on their remarks.

John Gaquin

[Bob Gardner]

I would never have picked up on it, but the aviation magazines made a big
thing of it at the time.

Bob Gardner

"Robert Moore" > wrote in message
. 8...
> "Bob Gardner" > wrote
>
> > This reminds me of the time when LearJet got a jet certified for 51,000
> > feet...the photograph in the aviation press showed both pilots smiling
> > into the camera at FL510 without an oxygen mask in sight. Always
> > wondered how the FAA reacted to that.
>
> They probably had "quick donners" available, which modifies the reg.
>
> Bob Moore

[G.R. Patterson III]

Aviation wrote:
>
> Do they put their oxygen masks on FIRST or start the dive first?

Masks go on first. After the Payne Weber incident, there was some discussion about
instituting a policy whereby at least one of the flight crew is wearing a mask at all
times above a certain altitude. I don't know if that was emplemented. Crews would set
the autopilot to perform the descent even if they lose consciousness.

> Someone also pointed out my goof about "holding" your breath
> upon going from cabin (8000 ft pressure) to ambient (25-35,000
> ft pressure). In estimating how much time the average civilian
> passenger could go without TAKING a breath of good air (14,000
> ft or below), I used the HOLD your breath estimate. Assuming
> there is 3-5 minutes of mask-oxygen and one minute of "holding"
> the last breath, they've got 3-6 minutes to get down to breathable
> (14,000 ft?) air and then below.

Once again. You cannot hold the last breath for 1 minute. You can't hold it for five
seconds. The air will rush out of your lungs as rapidly as it rushes out of the
plane,
and there isn't a single thing you can do about it. As soon as the pressure gets
below
about 10 psi, the oxygen will start to leave your bloodstream. You have perhaps 45
seconds before you turn into a babbling idiot - probably much less. If they don't get
you down to a decent altitude in less than about 4 minutes, you may stay a babbling
idiot for the rest of your life. A few more minutes, and you will probably die.

> For the movie Executive Decision,
> they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
> to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?

Mike Rappaport posted that his aircraft can descend at 10,000 fpm. He also posted
the opinion that many jets can do better than that.

> I found some rate of ASCENT data of about 3850 ft/min at
> http://www.altairva-fs.com/fleet/poh/Boeing%20747%20POH.htm
> but descent data isn't clear to me but it looks like 2500 ft/min
> from cruise altitude down to 10,000 ft is the recommended ROD.

Recommended descent rate goes out the window in an emergency. Think on it a little.
Most jet airliners top out between 400 and 500 mph. Idle the engines and point the
nose down, you should be able to get a rate of descent in excess of 25,000 fpm. Hit
500 knots straight down, and you're talking 50,000 fpm, but the pullout would
probably
pull the wings off.

> The discussion of the ear problem seems unsettled. Upon going
> from 8000 ft cabin pressure to 25000+ ft pressure in a couple
> of seconds (if loss of pressure is total), some rapid swallowing
> should equilibrate your ears to low pressure. Descending from
> 25,000+ (39,000) ft at 5,000 ft/min could result in reversible
> or IRREVERSIBLE damage depending on a person's ability to
> equilibrate REALLY fast.

If you have the presence of mind to do the exercises necessary to save your ears
when the pressure drops, perhaps you'd have the presence of mind to hold your
nose and blow into your ears on the way down? Even if you don't, it beats dying.

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

[Ralph Nesbitt]

"Mike Rapoport" > wrote in message
hlink.net...
>
> "Ralph Nesbitt" > wrote in message
> m...
> > Hopefully all realize when referring to "Air Pressure" at altitude this
is
> > an "absolute" pressure value inside the fuselage irrespective of
ambient.
> > When referring to air pressures at ground level the pressure reading is
> > above unadjusted ambient barometric pressure.
> >
> This is incorrect, pressurization is the differential between ambient and
> cabin preasure.
>
> Mike
> MU-2
>
Please reconsider your statement above as it applies to pressurization of
A/C cabins at altitude.

At altitude A/C cabins are like a pressure vessel. A/C cabins are
pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal atmospheric
pressure @ 11,000' ASL, in the cabin irrespective of altitude above 11,000'
ASL.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

> > A/C pressure systems are set to operate from departure point. If set
> > manually from info provided by ATC this is "Unadjusted Barometric
Presser"
> > read from an instrument at the base of the Tower, a specified height
above
> > the ramp. Most modern commercial A/C are equipped with automatic systems
> > that capture relevant data upon command/that is reset for each flight.
> > Ralph Nesbitt
> > Professional FD/CFR/ARFF Type
> >
> >
>
>

[Ralph Nesbitt]

"Robert Moore" > wrote in message
...
> "Ralph Nesbitt" wrote
> >
> > Hopefully all realize when referring to "Air Pressure" at altitude this
is
> > an "absolute" pressure value inside the fuselage irrespective of
ambient.
> > When referring to air pressures at ground level the pressure reading is
> > above unadjusted ambient barometric pressure.
>
> In the Boeing aircraft that I flew (B-727,B-707,B-720) there were two
> gages on the FE's panel. One was a simple altimeter that indicated the
> cabin altitude at all times and the other, a differential pressure gage
> that indicated the difference in pressure between outside and inside.
> The maximum differential for those aircraft was around 8.6 psi. The only
> way to determine the absolute pressure inside the aircraft would be to use
> a graph to convert the altimeter indication to pressure.
>
> Bob Moore
>
The protocols you reiterate above will translate to a ~ constant pressure of
12 PSI Gauge inside the cabin as the A/C moves through it's flight profile
above ~ 11,000'.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Ralph Nesbitt]

"Jon Woellhaf" > wrote in message
news:jvFIb.85543$VB2.191432@attbi_s51...
> During the explosive decompression portion of my Air Force altitude
chamber
> training, we sat in a small chamber adjacent to the larger main chamber
with
> our masks off. The airtight door between the two chambers was closed. The
> large chamber was evacuated to 50,000 feet, or so. We were at about 10,000
> feet and had our masks off.
>
> Without warning, the hatch between the chambers was suddenly opened. There
> was a loud bang, and the pressure in the two chambers very quickly
equalized
> to about 30,000 feet. The whole chamber filled with thick fog. I felt for
my
> mask and put it on.
>
> Ever after, I have been amused at the flight attendant's briefing, "In the
> unlikely event of a sudden loss of cabin pressure, the oxygen masks in
front
> of you will automatically deploy. Simply put the mask over your mouth and
> nose and breath normally. Etc. etc."
>
> Yeah, right! First there's a loud bang and everyone thinks a bomb has gone
> off. Then the cabin fills with super cold thick fog. The pilot puts the
> plane in a dive to get to breathable air and the masks are hanging a
couple
> feet in front of you. I think it would be absolute chaos.
>
> Have any of you experienced an actual explosive decompression while in
> flight?
>
> Jon
>
Never experienced it personally, but have met 4 A/C that have over my 40+/-
years of CFR/ARFF experience.

There were a few injuries from flying stuff, otherwise many had "Bloody
Noses", while some had "bleeding from the ears. In most instances those
injured by various "Flying Objects" showed signs of hypoxia.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Richard Riley]

Jim, if I install a transponder pin with a carbon fiber ground plane,
inside a fiberglass fuselage, what equipment is needed to see how well
it's working? Or do I just fly around and ask ATC "Can you see me
now? Can you see me now?"

(actually, I've already installed it, but I'm not flying yet.)


On Wed, 31 Dec 2003 15:57:13 -0800, Jim Weir > wrote:

:Yes, I got results on the carbon fiber and I would have SWORN that I posted them
:to this site.
:
:Putting a GPS antenna UNDER a small bowl-shaped carbon fiber radome immediately
:killed any GPS signal into a 27 dB gain active antenna INCLUDING satellites that
:were directly overhead.
:
:Figuring that the carbon was so lousy a transmissive path, I drilled a hole on
:the top of the bowl and used the bowl as the groundplane. VIOLA. The GPS
:antenna worked every bit as well on TOP of the carbon fiber as it did on a metal
:ground plane of approximately the same size.
:
:I can't say this is true for any other service than GPS (transponder, vhf nav &
:com, etc.) but it did test well for GPS.
:
:Jim
:
:
:
:Richard Riley >
:shared these priceless pearls of wisdom:
:
:->
:->Did you ever get results on the carbon?
:
:Jim Weir (A&P/IA, CFI, & other good alphabet soup)
:VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
:http://www.rst-engr.com

[Ralph Nesbitt]

"Cub Driver" > wrote in message
...
>
> > Was that in reference to a stray bullet causing the decompression?
> >If so, I'd have to agree that he's full of it.
>
> Yes, just so. He agreed that the sky marshal would have frangible
> bullets, but argued that the terrorist would not. That would lead to a
> bullet through the airplane (he didn't specify window, which I
> understand to be a problem) followed by explosive decompression "and
> all that that entails."
>
> all the best -- Dan Ford
The comments below are applicable to modern commercial Pax A/C. Anyone
familiar with the structure of an A/C will immediately ROFL at the idea of a
9mm bullet penetrating the external skin if fired from inside the cabin.

It would take a substantially more powerful weapon than a 9mm to cause a
"Window Failure", even then impact would have to be near 90 degrees because
of their "Plug design, plus they are thicker in the center than the edge
This curvature is on the inside.

The same applies to a bullet exiting through the A/C skin. Consider between
what is seen as the interior cabin wall & the "External Skin" of the A/C is
a layer of insulation, assorted wiring, plumbing in some places, plus
untold ribs, stiffeners, & other assorted structural components all of which
have some "Curvature" to them. All these components are riveted together
through "Lap Joints". All joints/connections are sealed with "Sealant" of
varying strengths.

The structure of an A/C is designed to flex, expand, & contract as the A/C
goes thru pressurization/de-pressurization cycles.

There are a few places a "Very High Velocity Bullet" of large caliber could
possibly exit the external skin if it the internal point of impact was at a
"very specific angle, very close to 90 degrees to external skin" if fired
from close range internally. Consider all the materials described above a
bullet would have to impact/penetrate, without its path being diverted by
some degree of ricochet.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Roger Halstead]

On Wed, 31 Dec 2003 16:04:08 -0500, "Ron Natalie" >
wrote:

>
>"Bob Gardner" > wrote in message news:bgFIb.16418$I07.44872@attbi_s53...
>> Well, it's been awhile, John, and I can hardly remember things that happened
>> last week, much less things that happened in the 70s. However, I do not
>> recall anything odd happening to my body during the ascent to 25000 but do
>> recall my lips doing the blub-blub-blub thing during the decompression. As
>> the pressure in the chamber rapidly increased, it kinda pushed the trapped
>> gas out.
>It's the other parts of your body doing the blub-blub-blub thing that's problematic.

Just remember it's absolutely essential to drink lots of beer, eat a
lot of chips with a hot dip and baked beans the night before to make
the altitude chamber a truely memorable experience.

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

[khobar]

Ralph Nesbitt > wrote in message
gy.com...
>
> "Robert Moore" > wrote in message
> ...
> > "Ralph Nesbitt" wrote
> > >
> > > Hopefully all realize when referring to "Air Pressure" at altitude
this
> is
> > > an "absolute" pressure value inside the fuselage irrespective of
> ambient.
> > > When referring to air pressures at ground level the pressure reading
is
> > > above unadjusted ambient barometric pressure.
> >
> > In the Boeing aircraft that I flew (B-727,B-707,B-720) there were two
> > gages on the FE's panel. One was a simple altimeter that indicated the
> > cabin altitude at all times and the other, a differential pressure gage
> > that indicated the difference in pressure between outside and inside.
> > The maximum differential for those aircraft was around 8.6 psi. The
only
> > way to determine the absolute pressure inside the aircraft would be to
use
> > a graph to convert the altimeter indication to pressure.
> >
> > Bob Moore
> >
> The protocols you reiterate above will translate to a ~ constant pressure
of
> 12 PSI Gauge inside the cabin as the A/C moves through it's flight profile
> above ~ 11,000'.
> Ralph Nesbitt
> Professional FD/CFR/ARFF Type

http://books.nap.edu/books/0309082897/html/36.html#pagetop

http://print.nap.edu/pdf/0309082897/pdf_image/36.pdf


Paul Nixon

[Scott M. Kozel]

"Ralph Nesbitt" > wrote:
>
> "Cub Driver" > wrote:
>
> > >Was that in reference to a stray bullet causing the decompression?
> > >If so, I'd have to agree that he's full of it.
> >
> > Yes, just so. He agreed that the sky marshal would have frangible
> > bullets, but argued that the terrorist would not. That would lead to a
> > bullet through the airplane (he didn't specify window, which I
> > understand to be a problem) followed by explosive decompression "and
> > all that that entails."
>
> The comments below are applicable to modern commercial Pax A/C. Anyone
> familiar with the structure of an A/C will immediately ROFL at the idea of a
> 9mm bullet penetrating the external skin if fired from inside the cabin.
>
> It would take a substantially more powerful weapon than a 9mm to cause a
> "Window Failure", even then impact would have to be near 90 degrees because
> of their "Plug design, plus they are thicker in the center than the edge
> This curvature is on the inside.
>
> The same applies to a bullet exiting through the A/C skin. Consider between
> what is seen as the interior cabin wall & the "External Skin" of the A/C is
> a layer of insulation, assorted wiring, plumbing in some places, plus
> untold ribs, stiffeners, & other assorted structural components all of which
> have some "Curvature" to them. All these components are riveted together
> through "Lap Joints". All joints/connections are sealed with "Sealant" of
> varying strengths.
>
> The structure of an A/C is designed to flex, expand, & contract as the A/C
> goes thru pressurization/de-pressurization cycles.
>
> There are a few places a "Very High Velocity Bullet" of large caliber could
> possibly exit the external skin if it the internal point of impact was at a
> "very specific angle, very close to 90 degrees to external skin" if fired
> from close range internally. Consider all the materials described above a
> bullet would have to impact/penetrate, without its path being diverted by
> some degree of ricochet.

Really? I saw a movie in the 1960s where a guy with a .38 revolver
tried to shoot another pax on an airliner (I think it was a DC-7), and
he missed and the slug went through the cabin wall and hit an engine and
set it on fire. :-]

[Jerry Hall]

When I conducted my first solo flight, it was pretty much a non-event
except that I had the plane to myself. After about thirty minutes of
dual - read that as two of us in the airplane, student (me) and the
instructor - including several landings at a controlled (has a tower)
airport, the instructor had me taxi over to the base of the tower and
shut the airplane down. He then asked for my log book and scribbled an
endorsement in the back certifying that I was qualified for solo flight.
Mind you, I had already received ten hours of flight training up to that
point plus extensive text work as well. He then told me to keep the
airplane "in the pattern", i.e. don't leave the controlled airspace
surrounding the airport: approximately a five mile radius. I was then
to perform three "touch and goes" - landings in which you place the
airplane on the runway but do not come to a stop but rather retract the
flaps while still rolling, apply power, and takeoff again. Then I was
to land with a full stop and return to the tower. He said he would
watch with the controllers. Geez, now I had an audience. I contacted
the tower via radio and was given clearance to takeoff and stay in the
pattern. I remembered I was literally shaking, not with fear but with
exhilaration. "Don't screw this up, don't screw this up," was my
mantra. I advanced the throttle once I was positioned on the centerline
of the runway and, in my estimation, the little Cessna 152 leapt
forward, unencumbered by the weight of a second person. Reaching 50
knots, I gently pulled back on the yoke and the plane rotated and
departed the runway. "WOW! I was flying! Really flying! I was in
control! I am a pilot!"
It was all I could do to not start whistling the theme from "The High
and the Mighty." The rest is history. Many hundreds and hundreds of
flight hours (PIC or Pilot In Command) later and innummerable aircraft,
I find myself grounded due to diabetes. Nothing will ever quite compare
to that first solo flight. God I miss it. Jerry


Aviation wrote:
> I have two questions inspired by Hollywood movies.
>
> In the movies (Goldfinger, Executive Decision and so on),
> when pressurized aircraft suffer catastrophic decompression
> at high (25000+ feet) altitude (usually when the bad guy
> shoots a bullet through a window) everything not tied down
> gets sucked out of the plane and the aircraft goes into an
> immediate, rapid nose dive and the pilots or the good guys
> have to struggle to level it off or prevent a crash.
>
> Is this an automatic "safety" feature of real, regular aircraft?
> On the one hand, passengers need to get denser air to breathe
> but large aircraft have oxygen masks that drop down. (I could
> do some rough estimates that the average fat slob can hold
> their breath for less than a minute so, without masks, the jet
> would have to go from let's say 30000 feet to 5000 feet in
> 30-45 seconds. My ears would explode.)
>
> I would think that a crash dive to a lower altitude could be
> even more dangerous such as if it occurred in a crowded air
> corridor. Maybe there are other dangers.
>
> What REALLY happens (or is supposed to happen) in the event
> of sudden decompression of real high flying aircraft?
>
>
>
> The second Hollywood inspired question comes from Executive
> Decision (1996). The main character is taking flying lessons
> in a single prop 2-seater plane and lands. The plane is still
> running (on the ground) and his instructor says, 'I think
> you're ready to solo' and gets out. The main character starts
> to taxi and then other non-flying plot developments happen.
> I was wondering if taking your FIRST solo flight is that simple.
>
> The location in the film in Washington, DC but I figure all
> US flying is FAA regulated. Wouldn't the first time soloist
> have to fill out some forms, file a flight plan with the
> airport and maybe even do a complete pre-flight check on the
> aircraft? Is the simplified movie solo flight completely
> bogus or could it happen that way?
>
>
> THANK YOU VERY MUCH.
>
>
>
>
>
>

[John E. Carty]

"Jerry Hall" > wrote in message
...
> When I conducted my first solo flight, it was pretty much a non-event
> except that I had the plane to myself. After about thirty minutes of
> dual - read that as two of us in the airplane, student (me) and the
> instructor - including several landings at a controlled (has a tower)
> airport, the instructor had me taxi over to the base of the tower and shut
> the airplane down. He then asked for my log book and scribbled an
> endorsement in the back certifying that I was qualified for solo flight.
> Mind you, I had already received ten hours of flight training up to that
> point plus extensive text work as well. He then told me to keep the
> airplane "in the pattern", i.e. don't leave the controlled airspace
> surrounding the airport: approximately a five mile radius. I was then to
> perform three "touch and goes" - landings in which you place the airplane
> on the runway but do not come to a stop but rather retract the flaps while
> still rolling, apply power, and takeoff again. Then I was to land with a
> full stop and return to the tower. He said he would watch with the
> controllers. Geez, now I had an audience. I contacted the tower via
> radio and was given clearance to takeoff and stay in the pattern. I
> remembered I was literally shaking, not with fear but with exhilaration.
> "Don't screw this up, don't screw this up," was my mantra. I advanced the
> throttle once I was positioned on the centerline of the runway and, in my
> estimation, the little Cessna 152 leapt forward, unencumbered by the
> weight of a second person. Reaching 50 knots, I gently pulled back on the
> yoke and the plane rotated and departed the runway. "WOW! I was flying!
> Really flying! I was in control! I am a pilot!"
> It was all I could do to not start whistling the theme from "The High and
> the Mighty." The rest is history.

>Many hundreds and hundreds of flight hours (PIC or Pilot In Command) later
>and innummerable aircraft, I find myself grounded due to diabetes.

Have you thought about getting a special issuance (if your diabetes is under
fairly good control) to get your medical back and start flying again? :-)

>Nothing will ever quite compare to that first solo flight. God I miss it.
>Jerry
>
>
> Aviation wrote:
>> I have two questions inspired by Hollywood movies.
>>
>> In the movies (Goldfinger, Executive Decision and so on), when
>> pressurized aircraft suffer catastrophic decompression
>> at high (25000+ feet) altitude (usually when the bad guy shoots a bullet
>> through a window) everything not tied down gets sucked out of the plane
>> and the aircraft goes into an immediate, rapid nose dive and the pilots
>> or the good guys have to struggle to level it off or prevent a crash. Is
>> this an automatic "safety" feature of real, regular aircraft? On the one
>> hand, passengers need to get denser air to breathe but large aircraft
>> have oxygen masks that drop down. (I could do some rough estimates that
>> the average fat slob can hold their breath for less than a minute so,
>> without masks, the jet
>> would have to go from let's say 30000 feet to 5000 feet in 30-45 seconds.
>> My ears would explode.)
>>
>> I would think that a crash dive to a lower altitude could be even more
>> dangerous such as if it occurred in a crowded air corridor. Maybe there
>> are other dangers.
>>
>> What REALLY happens (or is supposed to happen) in the event
>> of sudden decompression of real high flying aircraft? The second
>> Hollywood inspired question comes from Executive
>> Decision (1996). The main character is taking flying lessons
>> in a single prop 2-seater plane and lands. The plane is still
>> running (on the ground) and his instructor says, 'I think you're ready to
>> solo' and gets out. The main character starts to taxi and then other
>> non-flying plot developments happen. I was wondering if taking your
>> FIRST solo flight is that simple. The location in the film in
>> Washington, DC but I figure all
>> US flying is FAA regulated. Wouldn't the first time soloist have to fill
>> out some forms, file a flight plan with the airport and maybe even do a
>> complete pre-flight check on the aircraft? Is the simplified movie solo
>> flight completely bogus or could it happen that way?
>>
>>
>> THANK YOU VERY MUCH.
>>
>>
>>
>

[Dennis O'Connor]

After roughly ten seconds at 25K all thinking is backwards..
Denny

"Tom Fleischman" > wrote > You're
thinking backwards, Bob.

[Ron Natalie]

"Ralph Nesbitt" > wrote in message gy.com...

>
> At altitude A/C cabins are like a pressure vessel. A/C cabins are
> pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal atmospheric
> pressure @ 11,000' ASL, in the cabin irrespective of altitude above 11,000'

Actually, 8,000' (at least in US certificated transports).

[Morgans]

"John E. Carty" > wrote

> >Many hundreds and hundreds of flight hours (PIC or Pilot In Command)
later
> >and innummerable aircraft, I find myself grounded due to diabetes.
>
> Have you thought about getting a special issuance (if your diabetes is
under
> fairly good control) to get your medical back and start flying again? :-)
>
> >Nothing will ever quite compare to that first solo flight. God I miss
it.
> >Jerry
> >
> >
Get a pump, and one of those sugar checkers that records every reading, and
getting back into the air should be no big deal. Do it!
--
Jim in NC

[Morgans]

"John E. Carty" > wrote

> >Many hundreds and hundreds of flight hours (PIC or Pilot In Command)
later
> >and innummerable aircraft, I find myself grounded due to diabetes.
>
> Have you thought about getting a special issuance (if your diabetes is
under
> fairly good control) to get your medical back and start flying again? :-)
>
> >Nothing will ever quite compare to that first solo flight. God I miss
it.
> >Jerry
> >
> >
Get a pump, and one of those sugar checkers that records every reading, and
getting back into the air should be no big deal. Do it!
--
Jim in NC

[[email protected]]

On 31-Dec-2003, Jim Weir > wrote:

> Putting a GPS antenna UNDER a small bowl-shaped carbon fiber radome
> immediately
> killed any GPS signal into a 27 dB gain active antenna INCLUDING
> satellites that
> were directly overhead.


Yes, carbon fiber is an excellent RF absorber, particularly at GPS
frequencies.

--
-Elliott Drucker

[Jerry Hall]

John. It seems that once you move from oral medication to insulin as a
treatment for diabetes, that is the death knell to one's medical
certificate. Lord knows I've certainly jumped through a lot of hoops.
Several years ago the FAA medical folks as much as said, "Give it up,
turkey. You're not getting your medical reinstated." I go through a
similar line of BS in keeping my automobile driver's license. And my
glucose readings seldom go over 140. Have been hoping the newer "Sport"
license might allow me to fly again. Then there are ultralights but
that just isn't quite the same thing. To steal a line from Top Gun, I
feel the need for speed. Had a 177 RG. Jerry

John E. Carty wrote:
> "Jerry Hall" > wrote in message
> ...
>
>>When I conducted my first solo flight, it was pretty much a non-event
>>except that I had the plane to myself. After about thirty minutes of
>>dual - read that as two of us in the airplane, student (me) and the
>>instructor - including several landings at a controlled (has a tower)
>>airport, the instructor had me taxi over to the base of the tower and shut
>>the airplane down. He then asked for my log book and scribbled an
>>endorsement in the back certifying that I was qualified for solo flight.
>>Mind you, I had already received ten hours of flight training up to that
>>point plus extensive text work as well. He then told me to keep the
>>airplane "in the pattern", i.e. don't leave the controlled airspace
>>surrounding the airport: approximately a five mile radius. I was then to
>>perform three "touch and goes" - landings in which you place the airplane
>>on the runway but do not come to a stop but rather retract the flaps while
>>still rolling, apply power, and takeoff again. Then I was to land with a
>>full stop and return to the tower. He said he would watch with the
>>controllers. Geez, now I had an audience. I contacted the tower via
>>radio and was given clearance to takeoff and stay in the pattern. I
>>remembered I was literally shaking, not with fear but with exhilaration.
>>"Don't screw this up, don't screw this up," was my mantra. I advanced the
>>throttle once I was positioned on the centerline of the runway and, in my
>>estimation, the little Cessna 152 leapt forward, unencumbered by the
>>weight of a second person. Reaching 50 knots, I gently pulled back on the
>>yoke and the plane rotated and departed the runway. "WOW! I was flying!
>>Really flying! I was in control! I am a pilot!"
>>It was all I could do to not start whistling the theme from "The High and
>>the Mighty." The rest is history.
>
>
>>Many hundreds and hundreds of flight hours (PIC or Pilot In Command) later
>>and innummerable aircraft, I find myself grounded due to diabetes.
>
>
> Have you thought about getting a special issuance (if your diabetes is under
> fairly good control) to get your medical back and start flying again? :-)
>
>
>>Nothing will ever quite compare to that first solo flight. God I miss it.
>>Jerry
>>
>>
>>Aviation wrote:
>>
>>>I have two questions inspired by Hollywood movies.
>>>
>>>In the movies (Goldfinger, Executive Decision and so on), when
>>>pressurized aircraft suffer catastrophic decompression
>>>at high (25000+ feet) altitude (usually when the bad guy shoots a bullet
>>>through a window) everything not tied down gets sucked out of the plane
>>>and the aircraft goes into an immediate, rapid nose dive and the pilots
>>>or the good guys have to struggle to level it off or prevent a crash. Is
>>>this an automatic "safety" feature of real, regular aircraft? On the one
>>>hand, passengers need to get denser air to breathe but large aircraft
>>>have oxygen masks that drop down. (I could do some rough estimates that
>>>the average fat slob can hold their breath for less than a minute so,
>>>without masks, the jet
>>>would have to go from let's say 30000 feet to 5000 feet in 30-45 seconds.
>>>My ears would explode.)
>>>
>>>I would think that a crash dive to a lower altitude could be even more
>>>dangerous such as if it occurred in a crowded air corridor. Maybe there
>>>are other dangers.
>>>
>>>What REALLY happens (or is supposed to happen) in the event
>>>of sudden decompression of real high flying aircraft? The second
>>>Hollywood inspired question comes from Executive
>>>Decision (1996). The main character is taking flying lessons
>>>in a single prop 2-seater plane and lands. The plane is still
>>>running (on the ground) and his instructor says, 'I think you're ready to
>>>solo' and gets out. The main character starts to taxi and then other
>>>non-flying plot developments happen. I was wondering if taking your
>>>FIRST solo flight is that simple. The location in the film in
>>>Washington, DC but I figure all
>>>US flying is FAA regulated. Wouldn't the first time soloist have to fill
>>>out some forms, file a flight plan with the airport and maybe even do a
>>>complete pre-flight check on the aircraft? Is the simplified movie solo
>>>flight completely bogus or could it happen that way?
>>>
>>>
>>>THANK YOU VERY MUCH.
>>>
>>>
>>>
>>
>
>

[Ralph Nesbitt]

"khobar" > wrote in message
news:c4QIb.16727$7D3.2605@fed1read02...
> Ralph Nesbitt > wrote in message
> gy.com...
> >
> > "Robert Moore" > wrote in message
> > ...
> > > "Ralph Nesbitt" wrote
> > > >
> > > > Hopefully all realize when referring to "Air Pressure" at altitude
> this
> > is
> > > > an "absolute" pressure value inside the fuselage irrespective of
> > ambient.
> > > > When referring to air pressures at ground level the pressure reading
> is
> > > > above unadjusted ambient barometric pressure.
> > >
> > > In the Boeing aircraft that I flew (B-727,B-707,B-720) there were two
> > > gages on the FE's panel. One was a simple altimeter that indicated
the
> > > cabin altitude at all times and the other, a differential pressure
gage
> > > that indicated the difference in pressure between outside and inside.
> > > The maximum differential for those aircraft was around 8.6 psi. The
> only
> > > way to determine the absolute pressure inside the aircraft would be to
> use
> > > a graph to convert the altimeter indication to pressure.
> > >
> > > Bob Moore
> > >
> > The protocols you reiterate above will translate to a ~ constant
pressure
> of
> > 12 PSI Gauge inside the cabin as the A/C moves through it's flight
profile
> > above ~ 11,000'.
> > Ralph Nesbitt
> > Professional FD/CFR/ARFF Type
>
> http://books.nap.edu/books/0309082897/html/36.html#pagetop
>
> http://print.nap.edu/pdf/0309082897/pdf_image/36.pdf
>
>
> Paul Nixon
>
Thanks for detailed "Technical Spec's" for A/C pressurization.


My number of ~12 PSI Gauge was based on rule of thumb used by FD/CFR/ARFF
for off the cuff calculation of A/C pressurization & apparatus pump flow
rates; re 75% of 15.8 lbs (11.85 to 12) or 31.6 inches of mercury barometric
pressure rounded to closest number with 100% humidity at sea level. In
winter 75% of 14.4 lbs (10.8 to 11) or 28.7 inches of mercury barometric
pressure rounded to closest number with 100% humidity. These values are
"Rule of Thumb" ranges "Normally Encountered". Unusual atmospheric
conditions can cause higher or lower Barometric pressure values.

To determine exact PSIG it is necessary to use "unadjusted barometric
pressure values at any given location".

The variance in range of barometric pressures encountered is why
pressurization systems are based on "Relative Values" instead of absolute
values".
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Ralph Nesbitt]

"Scott M. Kozel" > wrote in message
...
> "Ralph Nesbitt" > wrote:
> >
> > "Cub Driver" > wrote:
> >
> > > >Was that in reference to a stray bullet causing the decompression?
> > > >If so, I'd have to agree that he's full of it.
> > >
> > > Yes, just so. He agreed that the sky marshal would have frangible
> > > bullets, but argued that the terrorist would not. That would lead to a
> > > bullet through the airplane (he didn't specify window, which I
> > > understand to be a problem) followed by explosive decompression "and
> > > all that that entails."
> >
> > The comments below are applicable to modern commercial Pax A/C. Anyone
> > familiar with the structure of an A/C will immediately ROFL at the idea
of a
> > 9mm bullet penetrating the external skin if fired from inside the cabin.
> >
> > It would take a substantially more powerful weapon than a 9mm to cause a
> > "Window Failure", even then impact would have to be near 90 degrees
because
> > of their "Plug design, plus they are thicker in the center than the edge
> > This curvature is on the inside.
> >
> > The same applies to a bullet exiting through the A/C skin. Consider
between
> > what is seen as the interior cabin wall & the "External Skin" of the A/C
is
> > a layer of insulation, assorted wiring, plumbing in some places, plus
> > untold ribs, stiffeners, & other assorted structural components all of
which
> > have some "Curvature" to them. All these components are riveted together
> > through "Lap Joints". All joints/connections are sealed with "Sealant"
of
> > varying strengths.
> >
> > The structure of an A/C is designed to flex, expand, & contract as the
A/C
> > goes thru pressurization/de-pressurization cycles.
> >
> > There are a few places a "Very High Velocity Bullet" of large caliber
could
> > possibly exit the external skin if it the internal point of impact was
at a
> > "very specific angle, very close to 90 degrees to external skin" if
fired
> > from close range internally. Consider all the materials described above
a
> > bullet would have to impact/penetrate, without its path being diverted
by
> > some degree of ricochet.
>
> Really? I saw a movie in the 1960s where a guy with a .38 revolver
> tried to shoot another pax on an airliner (I think it was a DC-7), and
> he missed and the slug went through the cabin wall and hit an engine and
> set it on fire. :-]
>
Was that the 1 with the promotion for "Scenic Florida Vacation Property at
+/- 2' sea level" as a "Promotional Trailer"?
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Scott M. Kozel]

"Ralph Nesbitt" > wrote:
>
> "Scott M. Kozel" > wrote:
> > "Ralph Nesbitt" > wrote:
> >
> > > The structure of an A/C is designed to flex, expand, & contract as the A/C
> > > goes thru pressurization/de-pressurization cycles.
> > >
> > > There are a few places a "Very High Velocity Bullet" of large caliber could
> > > possibly exit the external skin if it the internal point of impact was at a
> > > "very specific angle, very close to 90 degrees to external skin" if fired
> > > from close range internally. Consider all the materials described above a
> > > bullet would have to impact/penetrate, without its path being diverted by
> > > some degree of ricochet.
> >
> > Really? I saw a movie in the 1960s where a guy with a .38 revolver
> > tried to shoot another pax on an airliner (I think it was a DC-7), and
> > he missed and the slug went through the cabin wall and hit an engine and
> > set it on fire. :-]
>
> Was that the 1 with the promotion for "Scenic Florida Vacation Property at
> +/- 2' sea level" as a "Promotional Trailer"?

It happened on a flight from San Francisco to Hawaii. :-)

[Big John]

Jon

I have friends who were hit in the pressurized cockpit of fighters and
experienced explosive decompression. Of course they were wearing their
masks and unless the hit made the plane un flyable they just returned
to base and landed.

Another example of explosive decompression was the British "Comet' Jet
Transport. The fuselage exploded and everything went to flight
altitude pressure. Of course the damage to the aircraft made it un
flyable so it crashed.

A current model transport I have heard about was the 737 out of Hawaii
a few years ago. Cabin blew out (due to corrosion) and a 'stew' was
lost (not strapped in). They flew the bird back and landed it with a
10 foot by 10 foot hole in the fuselage.

Probably some other instances but not hitting on all since my return
from FL and Xmas visit with my family.

Big John

In altitude chamber, when they demo the explosive decompression, there
is no ear problem as the air in the inner ear is blown out and goes to
the higher altitude (lower air pressure). The other way, on descent,
if you have an infection or blockage in the ear/sinus you can get
blockage very easy. You should remember that you have to clear your
ears on a normal descent for landing from cruising cabin pressure
altitude on a commercial jet (that's going from a lower pressure to a
higher pressure).

HAPPY NEW YEARS TO ALL


----clip----

>Have any of you experienced an actual explosive decompression while in
>flight?
>
>Jon
>

[Big John]

Robert

You may know or someone?

As I recall there are some times when one of the pilots has to wear a
mask. Is it above a certain altitude or some other condition (like one
pilot leaving the cockpit???)

Remember it was a safety measure.

Big John


On Wed, 31 Dec 2003 23:13:10 GMT, Robert Moore
> wrote:

>"John Gaquin" > wrote
>> Truth is, if you're cruising at FL350 or higher you've only got about 5
>> seconds max to get the mask on, but it only takes about one to two
>> seconds to don the mask and get full O2 flowing.
>
>From the following web site:
>
>http://www.sff.net/people/Geoffrey.Landis/vacuum.html
>
>A larger body of information about how long you would remain conscious comes
>from aviation medicine. Aviation medicine defines the "time of useful
>consciousness", that is, how long after a decompression incident pilots will
>be awake and be sufficiently aware to take active measures to save their
>lives. Above 40,000 feet (12 km), the time of useful consciousness is 12 to
>25 seconds. (The shorter figure is for a person actively moving; the longer
>figure is for a person sitting quietly.)
>
>The number that we were always taught in the airline business was that at
>39,000', the time of useful conciousness was 18 seconds.
>
>Bob Moore

[C J Campbell]

Most movies use physics from an alternate universe. Bullets flash when they
hit things (even wood!). People outrun shock waves from explosions. The MAC
10 holds an infinite amount of ammo. You can poison a whole airplane by
contaminating the pressurization and/or the oxygen system. Alternatively,
the airplane pressurization will keep a plane filled with air even under
water. Small aircraft routinely outclimb and run into airliners.

As for Goldfinger, I suppose he *could* have hit the elevator and jammed it
when he was sucked out. But, really, why let the facts get in the way of a
good story?

As for solo flight, usually I just sign the student's log book and get out
of the airplane. I will have already briefed him on what I want him to do
during the solo -- three takeoffs and landings. A flight plan is not
required for VFR flight in the United States and most pilots do not file
one, especially if they are just going to remain in the local pattern. It is
only used for search and rescue, although some areas demanding extra
security since 9/11 also require a flight plan. The student would not call
the tower if there was no tower at the airport.

[C J Campbell]

"Dr. George O. Bizzigotti" > wrote in message
...
|
| One aspect that I have not seen addressed in this thread is the fact
| that most oxygen systems can provide supplemental oxygen for a few
| minutes only (I dimly recall figures like 3-5 minutes, but that may be
| inaccurate). The pilots also need to get down to 10,000 feet within
| that time before everyone's oxygen generators run out.
|

It really does not matter. The worst that will happen is that some people
will pass out, but it would be life threatening only to a very frail person.
As the airplane descends the time of useful consciousness increases rapidly,
so that oxygen would really only be needed for the first few minutes of
descent.

[David CL Francis]

On Wed, 31 Dec 2003 at 19:32:31 in message
<jvFIb.85543$VB2.191432@attbi_s51>, Jon Woellhaf
> wrote:

>Yeah, right! First there's a loud bang and everyone thinks a bomb has gone
>off. Then the cabin fills with super cold thick fog. The pilot puts the
>plane in a dive to get to breathable air and the masks are hanging a couple
>feet in front of you. I think it would be absolute chaos.
>
>Have any of you experienced an actual explosive decompression while in
>flight?

The nearest case I can find a record of is the 747-122 N44713U incident
on February 24, 1989.

It was climbing out of Hawaii when at 23,000 ft the front cargo door
blew off. This went with a big bang and took a large section of cabin
wall above with it. 9 passengers were ejected and never found, all but
one from the outer pairs of seats. There was a sudden thump followed by
'a mind shattering explosion'. The aircraft lurched, there was a huge
jump in wind noise and sudden misting of the cabin and flight deck. It
was dark and the lights went out. Many thought their last hour had come.
The cabin altitude warning sounded, the crew started an emergency
descent and turned 180 degrees to head back to Honolulu. No 3 engine was
now losing power. The gap in the skin extended up as far as the upper
deck windows.

The aircraft was landed. 17 passengers suffered injuries.

That was a very big hole!
--
David CL Francis

[khobar]

C J Campbell > wrote in message
...
> Most movies use physics from an alternate universe. Bullets flash when
they
> hit things (even wood!). People outrun shock waves from explosions. The
MAC
> 10 holds an infinite amount of ammo. You can poison a whole airplane by
> contaminating the pressurization and/or the oxygen system. Alternatively,
> the airplane pressurization will keep a plane filled with air even under
> water. Small aircraft routinely outclimb and run into airliners.
>
> As for Goldfinger, I suppose he *could* have hit the elevator and jammed
it
> when he was sucked out. But, really, why let the facts get in the way of a
> good story?
>

http://news.bbc.co.uk/2/hi/uk_news/3039583.stm

An interesting take on the situation especially in light of the fact that
there has been a case of a cabin window being shattered by engine debris
resulting in a PAX being blown out through that window.

Paul Nixon

[Robert Moore]

Big John > wrote
> As I recall there are some times when one of the pilots has to wear a
> mask. Is it above a certain altitude or some other condition (like one
> pilot leaving the cockpit???)

Yes...above FL240, if one pilot leaves the cockpit, the remaining
one must wear the mask and use the oxygen. From my own personal
experience, it was not very well enforced at any airline. At PanAm,
the PIC was encouraged to drill the crew in donning the masks with
one hand in less than the required 5 seconds.

Bob Moore

[David CL Francis]

On Wed, 31 Dec 2003 at 11:53:49 in message
>, Scott M. Kozel > wrote:

>How could an SST like the Concorde get from cruising altitude down to
>10,000 feet in 3-5 minutes?

I believe with the two inboard engines on reverse thrust the outer two
on idle. On my only Concorde flight (a test with volunteer passengers)
we descended from cruise height with two engines on reverse thrust. All
I remember was that the clouds below seemed to come up very fast!
--
David CL Francis

[David G. Nagel]

Contrary to popular opinion you may be on insulin and get a 3rd class
medical. You must only keep you A1C sugar within limits, pass a series
of medical tests and follow a test regimen during flight quarters. The
fly in the ointment is that you must have a flight physical every 90
days. This correlates with the A1C blood glucose test.
I am a difficult diabetic patient. I have not stabilized to a
significant enough degree as to be able to pass the A1c. BTW the limits
are very liberal for passing. The other problem is that the tests can
cost several thousand dollars but only have to be done once. Your
glucose is very much within tolerance and if you have no nerve or blood
circulation problems you should be able to qualify. I'm still working on it.
This program has been in effect for more than 5 years I believe.

Dave Nagel

Jerry Hall wrote:
> John. It seems that once you move from oral medication to insulin as a
> treatment for diabetes, that is the death knell to one's medical
> certificate. Lord knows I've certainly jumped through a lot of hoops.
> Several years ago the FAA medical folks as much as said, "Give it up,
> turkey. You're not getting your medical reinstated." I go through a
> similar line of BS in keeping my automobile driver's license. And my
> glucose readings seldom go over 140. Have been hoping the newer "Sport"
> license might allow me to fly again. Then there are ultralights but
> that just isn't quite the same thing. To steal a line from Top Gun, I
> feel the need for speed. Had a 177 RG. Jerry
>
> John E. Carty wrote:
>
>> "Jerry Hall" > wrote in message
>> ...
>>
>>> When I conducted my first solo flight, it was pretty much a non-event
>>> except that I had the plane to myself. After about thirty minutes of
>>> dual - read that as two of us in the airplane, student (me) and the
>>> instructor - including several landings at a controlled (has a tower)
>>> airport, the instructor had me taxi over to the base of the tower and
>>> shut the airplane down. He then asked for my log book and scribbled
>>> an endorsement in the back certifying that I was qualified for solo
>>> flight. Mind you, I had already received ten hours of flight training
>>> up to that point plus extensive text work as well. He then told me
>>> to keep the airplane "in the pattern", i.e. don't leave the
>>> controlled airspace surrounding the airport: approximately a five
>>> mile radius. I was then to perform three "touch and goes" - landings
>>> in which you place the airplane on the runway but do not come to a
>>> stop but rather retract the flaps while still rolling, apply power,
>>> and takeoff again. Then I was to land with a full stop and return to
>>> the tower. He said he would watch with the controllers. Geez, now I
>>> had an audience. I contacted the tower via radio and was given
>>> clearance to takeoff and stay in the pattern. I remembered I was
>>> literally shaking, not with fear but with exhilaration. "Don't screw
>>> this up, don't screw this up," was my mantra. I advanced the
>>> throttle once I was positioned on the centerline of the runway and,
>>> in my estimation, the little Cessna 152 leapt forward, unencumbered
>>> by the weight of a second person. Reaching 50 knots, I gently pulled
>>> back on the yoke and the plane rotated and departed the runway.
>>> "WOW! I was flying! Really flying! I was in control! I am a pilot!"
>>> It was all I could do to not start whistling the theme from "The High
>>> and the Mighty." The rest is history.
>>
>>
>>
>>> Many hundreds and hundreds of flight hours (PIC or Pilot In Command)
>>> later and innummerable aircraft, I find myself grounded due to diabetes.
>>
>>
>>
>> Have you thought about getting a special issuance (if your diabetes is
>> under fairly good control) to get your medical back and start flying
>> again? :-)
>>
>>
>>> Nothing will ever quite compare to that first solo flight. God I
>>> miss it. Jerry
>>>
>>>
>>> Aviation wrote:
>>>
>>>> I have two questions inspired by Hollywood movies.
>>>>
>>>> In the movies (Goldfinger, Executive Decision and so on), when
>>>> pressurized aircraft suffer catastrophic decompression
>>>> at high (25000+ feet) altitude (usually when the bad guy shoots a
>>>> bullet through a window) everything not tied down gets sucked out of
>>>> the plane and the aircraft goes into an immediate, rapid nose dive
>>>> and the pilots or the good guys have to struggle to level it off or
>>>> prevent a crash. Is this an automatic "safety" feature of real,
>>>> regular aircraft? On the one hand, passengers need to get denser
>>>> air to breathe but large aircraft have oxygen masks that drop down.
>>>> (I could do some rough estimates that the average fat slob can hold
>>>> their breath for less than a minute so, without masks, the jet
>>>> would have to go from let's say 30000 feet to 5000 feet in 30-45
>>>> seconds. My ears would explode.)
>>>>
>>>> I would think that a crash dive to a lower altitude could be even
>>>> more dangerous such as if it occurred in a crowded air corridor.
>>>> Maybe there are other dangers.
>>>>
>>>> What REALLY happens (or is supposed to happen) in the event
>>>> of sudden decompression of real high flying aircraft? The second
>>>> Hollywood inspired question comes from Executive
>>>> Decision (1996). The main character is taking flying lessons
>>>> in a single prop 2-seater plane and lands. The plane is still
>>>> running (on the ground) and his instructor says, 'I think you're
>>>> ready to solo' and gets out. The main character starts to taxi and
>>>> then other non-flying plot developments happen. I was wondering if
>>>> taking your FIRST solo flight is that simple. The location in the
>>>> film in Washington, DC but I figure all
>>>> US flying is FAA regulated. Wouldn't the first time soloist have to
>>>> fill out some forms, file a flight plan with the airport and maybe
>>>> even do a complete pre-flight check on the aircraft? Is the
>>>> simplified movie solo flight completely bogus or could it happen
>>>> that way?
>>>>
>>>>
>>>> THANK YOU VERY MUCH.
>>>>
>>>>
>>>>
>>>
>>
>>
>

[Jim Weir]

Would you mind keeping your gratuitous comments on the obvious to yourself?

Jim



shared these priceless pearls of wisdom:

->Yes, carbon fiber is an excellent RF absorber, particularly at GPS
->frequencies.

Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

[Ralph Nesbitt]

"Scott M. Kozel" > wrote in message
...
> "Ralph Nesbitt" > wrote:
> >
> > "Scott M. Kozel" > wrote:
> > > "Ralph Nesbitt" > wrote:
> > >
> > > > The structure of an A/C is designed to flex, expand, & contract as
the A/C
> > > > goes thru pressurization/de-pressurization cycles.
> > > >
> > > > There are a few places a "Very High Velocity Bullet" of large
caliber could
> > > > possibly exit the external skin if it the internal point of impact
was at a
> > > > "very specific angle, very close to 90 degrees to external skin" if
fired
> > > > from close range internally. Consider all the materials described
above a
> > > > bullet would have to impact/penetrate, without its path being
diverted by
> > > > some degree of ricochet.
> > >
> > > Really? I saw a movie in the 1960s where a guy with a .38 revolver
> > > tried to shoot another pax on an airliner (I think it was a DC-7), and
> > > he missed and the slug went through the cabin wall and hit an engine
and
> > > set it on fire. :-]
> >
> > Was that the 1 with the promotion for "Scenic Florida Vacation Property
at
> > +/- 2' sea level" as a "Promotional Trailer"?
>
> It happened on a flight from San Francisco to Hawaii. :-)
>
Saw the movie of trip between or flt segment in movie?
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Ralph Nesbitt]

"khobar" > wrote in message
news:%T1Jb.16822$7D3.7011@fed1read02...
> C J Campbell > wrote in message
> ...
> > Most movies use physics from an alternate universe. Bullets flash when
> they
> > hit things (even wood!). People outrun shock waves from explosions. The
> MAC
> > 10 holds an infinite amount of ammo. You can poison a whole airplane by
> > contaminating the pressurization and/or the oxygen system.
Alternatively,
> > the airplane pressurization will keep a plane filled with air even under
> > water. Small aircraft routinely outclimb and run into airliners.
> >
> > As for Goldfinger, I suppose he *could* have hit the elevator and jammed
> it
> > when he was sucked out. But, really, why let the facts get in the way of
a
> > good story?
> >
>
> http://news.bbc.co.uk/2/hi/uk_news/3039583.stm
>
> An interesting take on the situation especially in light of the fact that
> there has been a case of a cabin window being shattered by engine debris
> resulting in a PAX being blown out through that window.
>
> Paul Nixon
>
The "Ballistics Profile" of the most powerful hand gun "Pales in
comparison/is infatisimal compared to that of debris from an "Uncontained
Engine Failure".
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[John E. Carty]

Jerry Hall > wrote in message >...
> John. It seems that once you move from oral medication to insulin as a
> treatment for diabetes, that is the death knell to one's medical
> certificate. Lord knows I've certainly jumped through a lot of hoops.
> Several years ago the FAA medical folks as much as said, "Give it up,
> turkey. You're not getting your medical reinstated." I go through a
> similar line of BS in keeping my automobile driver's license. And my
> glucose readings seldom go over 140. Have been hoping the newer "Sport"
> license might allow me to fly again. Then there are ultralights but
> that just isn't quite the same thing. To steal a line from Top Gun, I
> feel the need for speed. Had a 177 RG. Jerry

Jerry,

That's how it used to be, but no more. I got mine back and I take
injections twice a day. Your blood sugars have to be between 100-300
thirty minutes prior to flight, and checked every two hours during
flight. Though I have to admit that if the Sport certification comes
through soon it'll probably be easier, and defiantely be cheaper, to
go that route.

Best of Luck,
John

>
> John E. Carty wrote:
> > "Jerry Hall" > wrote in message
> > ...
> >
> >>When I conducted my first solo flight, it was pretty much a non-event
> >>except that I had the plane to myself. After about thirty minutes of
> >>dual - read that as two of us in the airplane, student (me) and the
> >>instructor - including several landings at a controlled (has a tower)
> >>airport, the instructor had me taxi over to the base of the tower and shut
> >>the airplane down. He then asked for my log book and scribbled an
> >>endorsement in the back certifying that I was qualified for solo flight.
> >>Mind you, I had already received ten hours of flight training up to that
> >>point plus extensive text work as well. He then told me to keep the
> >>airplane "in the pattern", i.e. don't leave the controlled airspace
> >>surrounding the airport: approximately a five mile radius. I was then to
> >>perform three "touch and goes" - landings in which you place the airplane
> >>on the runway but do not come to a stop but rather retract the flaps while
> >>still rolling, apply power, and takeoff again. Then I was to land with a
> >>full stop and return to the tower. He said he would watch with the
> >>controllers. Geez, now I had an audience. I contacted the tower via
> >>radio and was given clearance to takeoff and stay in the pattern. I
> >>remembered I was literally shaking, not with fear but with exhilaration.
> >>"Don't screw this up, don't screw this up," was my mantra. I advanced the
> >>throttle once I was positioned on the centerline of the runway and, in my
> >>estimation, the little Cessna 152 leapt forward, unencumbered by the
> >>weight of a second person. Reaching 50 knots, I gently pulled back on the
> >>yoke and the plane rotated and departed the runway. "WOW! I was flying!
> >>Really flying! I was in control! I am a pilot!"
> >>It was all I could do to not start whistling the theme from "The High and
> >>the Mighty." The rest is history.
> >
> >
> >>Many hundreds and hundreds of flight hours (PIC or Pilot In Command) later
> >>and innummerable aircraft, I find myself grounded due to diabetes.
> >
> >
> > Have you thought about getting a special issuance (if your diabetes is under
> > fairly good control) to get your medical back and start flying again? :-)
> >
> >
> >>Nothing will ever quite compare to that first solo flight. God I miss it.
> >>Jerry
> >>
> >>
> >>Aviation wrote:
> >>
> >>>I have two questions inspired by Hollywood movies.
> >>>
> >>>In the movies (Goldfinger, Executive Decision and so on), when
> >>>pressurized aircraft suffer catastrophic decompression
> >>>at high (25000+ feet) altitude (usually when the bad guy shoots a bullet
> >>>through a window) everything not tied down gets sucked out of the plane
> >>>and the aircraft goes into an immediate, rapid nose dive and the pilots
> >>>or the good guys have to struggle to level it off or prevent a crash. Is
> >>>this an automatic "safety" feature of real, regular aircraft? On the one
> >>>hand, passengers need to get denser air to breathe but large aircraft
> >>>have oxygen masks that drop down. (I could do some rough estimates that
> >>>the average fat slob can hold their breath for less than a minute so,
> >>>without masks, the jet
> >>>would have to go from let's say 30000 feet to 5000 feet in 30-45 seconds.
> >>>My ears would explode.)
> >>>
> >>>I would think that a crash dive to a lower altitude could be even more
> >>>dangerous such as if it occurred in a crowded air corridor. Maybe there
> >>>are other dangers.
> >>>
> >>>What REALLY happens (or is supposed to happen) in the event
> >>>of sudden decompression of real high flying aircraft? The second
> >>>Hollywood inspired question comes from Executive
> >>>Decision (1996). The main character is taking flying lessons
> >>>in a single prop 2-seater plane and lands. The plane is still
> >>>running (on the ground) and his instructor says, 'I think you're ready to
> >>>solo' and gets out. The main character starts to taxi and then other
> >>>non-flying plot developments happen. I was wondering if taking your
> >>>FIRST solo flight is that simple. The location in the film in
> >>>Washington, DC but I figure all
> >>>US flying is FAA regulated. Wouldn't the first time soloist have to fill
> >>>out some forms, file a flight plan with the airport and maybe even do a
> >>>complete pre-flight check on the aircraft? Is the simplified movie solo
> >>>flight completely bogus or could it happen that way?
> >>>
> >>>
> >>>THANK YOU VERY MUCH.
> >>>
> >>>
> >>>
> >>
> >
> >

[Mike Rapoport]

"Ralph Nesbitt" > wrote in message
gy.com...
>
> "Mike Rapoport" > wrote in message
> hlink.net...
> >
> > "Ralph Nesbitt" > wrote in message
> > m...
> > > Hopefully all realize when referring to "Air Pressure" at altitude
this
> is
> > > an "absolute" pressure value inside the fuselage irrespective of
> ambient.
> > > When referring to air pressures at ground level the pressure reading
is
> > > above unadjusted ambient barometric pressure.
> > >
> > This is incorrect, pressurization is the differential between ambient
and
> > cabin preasure.
> >
> > Mike
> > MU-2
> >
> Please reconsider your statement above as it applies to pressurization of
> A/C cabins at altitude.
>
> At altitude A/C cabins are like a pressure vessel. A/C cabins are
> pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal atmospheric
> pressure @ 11,000' ASL, in the cabin irrespective of altitude above
11,000'
> ASL.
> Ralph Nesbitt
> Professional FD/CFR/ARFF Type

No, the cabin is not at a constant preasure above 11,000' (and the number
that you are looking for is 8,000') unless the rate controller is set to a
rate greater than the climb rate of the aircraft (which is never done). If
what you say were true then the cabin altitude would not climb with the
airplane above 11,000' (8,000') which it clearly does. If you doubt this,
go buy an altimeter watch and see for yourself. Or you could buy a
pressurized airplane.

Mike
MU-2

[Ralph Nesbitt]

I believe C J Campbell posted he could find only 1 reference to an explosive
decompression incident involveing commercial pax A/C.

The following, in no particular order are explosive decompression incidents
occuring over the past ~ 35 years in no particular order.

Several incidents involveing early DC-10's due a "Door Design Problem". 1
catastrophic incident involved Turkish Airlines in/over France. Another IRC
involved a NW Airlines A/C near Detroit that made a sucessful landing.

The pressure bulkhead of a 747 blew out in/over Japan with catastrophic
consequences.

A 737 on an inter island flight lost a section of it's top near Hawaii.

While military, another incident of note was the catastrophic crash of a C-5
carrying "Orphans" as it departed Saigon in the early 70's due explosive
decompression when the rear pressure door locks failed.

I apologize for not folowing the post in the thread, but MS OLE decided the
post in ? should disapear by "Crashing" my computer as I was responding.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Scott M. Kozel]

"Ralph Nesbitt" > wrote:
>
> "Scott M. Kozel" > wrote:
> > "Ralph Nesbitt" > wrote:
> > > "Scott M. Kozel" > wrote:
> > >
> > > > Really? I saw a movie in the 1960s where a guy with a .38 revolver
> > > > tried to shoot another pax on an airliner (I think it was a DC-7), and
> > > > he missed and the slug went through the cabin wall and hit an engine and
> > > > set it on fire. :-]
> > >
> > > Was that the 1 with the promotion for "Scenic Florida Vacation Property at
> > > +/- 2' sea level" as a "Promotional Trailer"?
> >
> > It happened on a flight from San Francisco to Hawaii. :-)
>
> Saw the movie of trip between or flt segment in movie?

This happened in the movie. Allright, someone please help me remember
the name of the movie!

I can't vouch for the exact caliber of the gun, but it looked like the
standard police special revolver of that era, which would have been a
..38 Special caliber.

After the engine fire burned awhile, the top of one of the cylinders
blew off, and then the flash of fuel detonation kept coming out with a
whomp!-whomp!-whomp!-whomp!-whomp!-whomp!-whomp!-whomp! It was at night
of course, and I'm not sure whether the crew eventually managed to
feather the prop and stop the engine.

[Ralph Nesbitt]

"Scott M. Kozel" > wrote in message
...
> "Ralph Nesbitt" > wrote:
> >
> > "Scott M. Kozel" > wrote:
> > > "Ralph Nesbitt" > wrote:
> > > > "Scott M. Kozel" > wrote:
> > > >
> > > > > Really? I saw a movie in the 1960s where a guy with a .38
revolver
> > > > > tried to shoot another pax on an airliner (I think it was a DC-7),
and
> > > > > he missed and the slug went through the cabin wall and hit an
engine and
> > > > > set it on fire. :-]
> > > >
> > > > Was that the 1 with the promotion for "Scenic Florida Vacation
Property at
> > > > +/- 2' sea level" as a "Promotional Trailer"?
> > >
> > > It happened on a flight from San Francisco to Hawaii. :-)
> >
> > Saw the movie of trip between or flt segment in movie?
>
> This happened in the movie. Allright, someone please help me remember
> the name of the movie!
>
> I can't vouch for the exact caliber of the gun, but it looked like the
> standard police special revolver of that era, which would have been a
> .38 Special caliber.
>
> After the engine fire burned awhile, the top of one of the cylinders
> blew off, and then the flash of fuel detonation kept coming out with a
> whomp!-whomp!-whomp!-whomp!-whomp!-whomp!-whomp!-whomp! It was at night
> of course, and I'm not sure whether the crew eventually managed to
> feather the prop and stop the engine.
> Ah the wonders of "Hollywood"
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Scott M. Kozel]

"Ralph Nesbitt" > wrote:
>
> "Scott M. Kozel" > wrote:
> > "Ralph Nesbitt" > wrote:
> > > "Scott M. Kozel" > wrote:
> > > > "Ralph Nesbitt" > wrote:
> > > > > "Scott M. Kozel" > wrote:
> > > > >
> > > > > > Really? I saw a movie in the 1960s where a guy with a .38 revolver
> > > > > > tried to shoot another pax on an airliner (I think it was a DC-7), and
> > > > > > he missed and the slug went through the cabin wall and hit an engine and
> > > > > > set it on fire. :-]
> > > > >
> > > > > Was that the 1 with the promotion for "Scenic Florida Vacation Property at
> > > > > +/- 2' sea level" as a "Promotional Trailer"?
> > > >
> > > > It happened on a flight from San Francisco to Hawaii. :-)
> > >
> > > Saw the movie of trip between or flt segment in movie?
> >
> > This happened in the movie. Allright, someone please help me remember
> > the name of the movie!
> >
> > I can't vouch for the exact caliber of the gun, but it looked like the
> > standard police special revolver of that era, which would have been a
> > .38 Special caliber.
> >
> > After the engine fire burned awhile, the top of one of the cylinders
> > blew off, and then the flash of fuel detonation kept coming out with a
> > whomp!-whomp!-whomp!-whomp!-whomp!-whomp!-whomp!-whomp! It was at night
> > of course, and I'm not sure whether the crew eventually managed to
> > feather the prop and stop the engine.
>
> Ah the wonders of "Hollywood"

Hee hee! If the guy had fired an M-1 service rifle, then I might think
that significant damage to the engine might have occurred.

[Thomas]

*David CL Francis wrote:
>
> The nearest case I can find a record of is the 747-122 N44713U incident
> on February 24, 1989.
>
> That was a very big hole!


Yes, it was:

http://dnausers.d-n-a.net/dnetGOjg/240289.gif

--
Thomas

[Tom Sixkiller]

Pardon?

Tom

"Jim Weir" > wrote in message
...
> Would you mind keeping your gratuitous comments on the obvious to
yourself?
>
> Jim
>
>
>
> shared these priceless pearls of wisdom:
>
> ->Yes, carbon fiber is an excellent RF absorber, particularly at GPS
> ->frequencies.
>
> Jim Weir (A&P/IA, CFI, & other good alphabet soup)
> VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
> http://www.rst-engr.com

[khobar]

Ralph Nesbitt > wrote in message
m...
>
> "khobar" > wrote in message
> news:%T1Jb.16822$7D3.7011@fed1read02...
> > C J Campbell > wrote in message
> > ...
> > > Most movies use physics from an alternate universe. Bullets flash when
> > they
> > > hit things (even wood!). People outrun shock waves from explosions.
The
> > MAC
> > > 10 holds an infinite amount of ammo. You can poison a whole airplane
by
> > > contaminating the pressurization and/or the oxygen system.
> Alternatively,
> > > the airplane pressurization will keep a plane filled with air even
under
> > > water. Small aircraft routinely outclimb and run into airliners.
> > >
> > > As for Goldfinger, I suppose he *could* have hit the elevator and
jammed
> > it
> > > when he was sucked out. But, really, why let the facts get in the way
of
> a
> > > good story?
> > >
> >
> > http://news.bbc.co.uk/2/hi/uk_news/3039583.stm
> >
> > An interesting take on the situation especially in light of the fact
that
> > there has been a case of a cabin window being shattered by engine debris
> > resulting in a PAX being blown out through that window.
> >
> > Paul Nixon
> >
> The "Ballistics Profile" of the most powerful hand gun "Pales in
> comparison/is infatisimal compared to that of debris from an "Uncontained
> Engine Failure".

A .22 pales in comparison to a cannonball, yet both are deadly under the
right circumstances.

What bullets, if any, possess sufficient energy to penetrate an airliner
window and would that airliner window spider or would said bullet simply
leave a small hole? We already know that an adult PAX will, apparently, fit
through a typical airliner window.

Paul Nixon

[C J Campbell]

|
| What bullets, if any, possess sufficient energy to penetrate an airliner
| window and would that airliner window spider or would said bullet simply
| leave a small hole? We already know that an adult PAX will, apparently,
fit
| through a typical airliner window.
|

We do not really know any such thing. If the passenger is bigger than the
window he simply cannot be pulled through it any more than he can sucked up
through a vacuum cleaner hose.

[Ron Natalie]

"C J Campbell" > wrote in message ...

> We do not really know any such thing. If the passenger is bigger than the
> window he simply cannot be pulled through it any more than he can sucked up
> through a vacuum cleaner hose.
>
Passengers are pretty flexible. Some might plug up the hole, others will
go through holes that looked like they ought not to fit through.

[C J Campbell]

"Ralph Nesbitt" > wrote in message
. ..
| I believe C J Campbell posted he could find only 1 reference to an
explosive
| decompression incident involveing commercial pax A/C.
|

No, I never made such a post. I have heard of all the incidents you
mentioned.

The incidents you cite generally involve the sudden loss of a door or hatch.
Passengers in the immediate vicinity can get sucked out, although not
through a window. In fact, I question if the loss of a window is enough to
cause an explosive decompression as opposed to a rapid decompression.

Aircraft have been lost or severely damaged by the loss of a door or hatch
as the cover and other debris can strike control surfaces, hydraulic lines
or engines.

In any event, surviving passengers on the subject aircraft did not swell up
and explode, have their eardrums burst, or any other such nonsense.

[C J Campbell]

"khobar" > wrote in message
news:%T1Jb.16822$7D3.7011@fed1read02...
| >
|
| http://news.bbc.co.uk/2/hi/uk_news/3039583.stm
|

Hysterical. These guys could not find one single fact to support their
idiocy, so they use the movies for a reference. No doubt they will be
worrying about bullets containing compressed air that can cause a human to
inflate and explode, too. What incredible silliness.

[C J Campbell]

"Ron Natalie" > wrote in message
m...
|
| "C J Campbell" > wrote in message
...
|
| > We do not really know any such thing. If the passenger is bigger than
the
| > window he simply cannot be pulled through it any more than he can sucked
up
| > through a vacuum cleaner hose.
| >
| Passengers are pretty flexible. Some might plug up the hole, others
will
| go through holes that looked like they ought not to fit through.
|

The windows are surprisingly large, too. I have no doubt that a small person
could get through one, especially if his seatbelt is not properly fastened.
However, you are not going to lose a whole planeload of passengers this way.
Given a choice, I would shoot a hijacker with the off chance of killing an
innocent bystander rather than allow the hijacker to drive the plane into a
crowded building.

[Ralph Nesbitt]

"khobar" > wrote in message
news:j1gJb.16912$7D3.7262@fed1read02...
> Ralph Nesbitt > wrote in message
> m...
> >
> > "khobar" > wrote in message
> > news:%T1Jb.16822$7D3.7011@fed1read02...
> > > C J Campbell > wrote in message
> > > ...
> > > > Most movies use physics from an alternate universe. Bullets flash
when
> > > they
> > > > hit things (even wood!). People outrun shock waves from explosions.
> The
> > > MAC
> > > > 10 holds an infinite amount of ammo. You can poison a whole airplane
> by
> > > > contaminating the pressurization and/or the oxygen system.
> > Alternatively,
> > > > the airplane pressurization will keep a plane filled with air even
> under
> > > > water. Small aircraft routinely outclimb and run into airliners.
> > > >
> > > > As for Goldfinger, I suppose he *could* have hit the elevator and
> jammed
> > > it
> > > > when he was sucked out. But, really, why let the facts get in the
way
> of
> > a
> > > > good story?
> > > >
> > >
> > > http://news.bbc.co.uk/2/hi/uk_news/3039583.stm
> > >
> > > An interesting take on the situation especially in light of the fact
> that
> > > there has been a case of a cabin window being shattered by engine
debris
> > > resulting in a PAX being blown out through that window.
> > >
> > > Paul Nixon
> > >
> > The "Ballistics Profile" of the most powerful hand gun "Pales in
> > comparison/is infatisimal compared to that of debris from an
"Uncontained
> > Engine Failure".
>
> A .22 pales in comparison to a cannonball, yet both are deadly under the
> right circumstances.
>
> What bullets, if any, possess sufficient energy to penetrate an airliner
> window and would that airliner window spider or would said bullet simply
> leave a small hole? We already know that an adult PAX will, apparently,
fit
> through a typical airliner window.
>
> Paul Nixon
>
I have no experience with "A/C Window Bullet Impact". Have seen "Spidering
due Debris" from "uncontained engine failures. Have seen, dealt with the
aftermath of encounters between fighter type A/C & large birds such as
"Buzzards, Eagles, or other large carrion Feeders.

For some reason the "Canopy of F-4's" were subject to shatter, disappear
upon impact with a large bird. For some reason the remains of "Buzzards",
especially, tended to remain in the cockpit. Makes for a smelly tedious
situation to safety ejection seats, especially those with "Banana Links,
check crew for injuries, then safely remove them from A/C.

The "Windshields of Southern 232", a DC-9, were broken out along with
"Catastrophic Engine Damage" by hail at altitude resulting in a catastrophic
incident. Many "Hail Stones of ~3" Diameter were in the cockpit when we
arrived on scene within ~ 7 minuets of the incident. There were substantial
"Dents/Dings" in the rear cockpit bulkhead from the "Hail Stones".
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[khobar]

C J Campbell > wrote in message
...
> |
> | What bullets, if any, possess sufficient energy to penetrate an airliner
> | window and would that airliner window spider or would said bullet simply
> | leave a small hole? We already know that an adult PAX will, apparently,
> fit
> | through a typical airliner window.
> |
>
> We do not really know any such thing. If the passenger is bigger than the
> window he simply cannot be pulled through it any more than he can sucked
up
> through a vacuum cleaner hose.

http://aviation-safety.net/database/1973/731103-0.htm

"As a result, the cabin depressurized and one cabin window, which was struck
by a fragment of the fan assembly, separated from the fuselage. The
passenger who was sitting next to that window was forced through the opening
and ejected from the aircraft."


http://www.super70s.com/Super70s/Tech/Aviation/Disasters/73-11-03(National).
asp

"According to a witness, the occupant of the seat was partially forced
through the window opening and was temporarily retained in this position by
his seatbelt. Efforts to pull the passenger back into the airplane by
another passenger were unsuccessful, and the occupant of seat 17H was
subsequently forced entirely through the cabin window."

Paul Nixon

[Ralph Nesbitt]

"C J Campbell" > wrote in message
...
>
As I stated previously MS/OE, my news reader, crashed as I was responding to
a post regarding "Explosive Decompression Incidents".

Hopefully Mr. Campbell will accept my apologies for improperly attributing
the post to him.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Ralph Nesbitt]

"khobar" > wrote in message
news:_7iJb.16944$7D3.30@fed1read02...
> C J Campbell > wrote in message
> ...
> > |
> > | What bullets, if any, possess sufficient energy to penetrate an
airliner
> > | window and would that airliner window spider or would said bullet
simply
> > | leave a small hole? We already know that an adult PAX will,
apparently,
> > fit
> > | through a typical airliner window.
> > |
> >
> > We do not really know any such thing. If the passenger is bigger than
the
> > window he simply cannot be pulled through it any more than he can sucked
> up
> > through a vacuum cleaner hose.
>
> http://aviation-safety.net/database/1973/731103-0.htm
>
> "As a result, the cabin depressurized and one cabin window, which was
struck
> by a fragment of the fan assembly, separated from the fuselage. The
> passenger who was sitting next to that window was forced through the
opening
> and ejected from the aircraft."
>
>
>
http://www.super70s.com/Super70s/Tech/Aviation/Disasters/73-11-03(National).
> asp
>
> "According to a witness, the occupant of the seat was partially forced
> through the window opening and was temporarily retained in this position
by
> his seatbelt. Efforts to pull the passenger back into the airplane by
> another passenger were unsuccessful, and the occupant of seat 17H was
> subsequently forced entirely through the cabin window."
>
> Paul Nixon
>
No doubt the pax in ? departed through the hole left by the "window".

"Windows for AC" are essentially like those used in houses, in that they are
"Prefab Units" of a specified size installed/secured in the structure of the
house or A/C.

Just as with a window in a house, there is a vast difference in the size
hole remaining between the glass being broken out, compared to the entire
Prefab Unit being forced from the structure.

The "Prefab Window" departing the A/C structure surely weakened the A/C
structure surrounding the "Departed Window".

In 1 of the above references, it is stated, the pax that lost was sitting in
seat 14L. #'s 1 & 2 engines were damaged by FOD from the #3 engine, plus
assorted damage to wings & their components.

It would be interesting to know if the engine fragment that caused the
"Window Failure" struck the window/window frame structure from inside or
outside.

Most uncontained engine failures result in damage to the A/C in patterns
at/near 90 degrees to the engine components "plane of rotation" for the
failed components.

Anyone know the angle between the "plane of rotation" for the "fan assembly"
of the #3 engine & engines #'s 1 & 2.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Mary Shafer]

On Wed, 31 Dec 2003 20:48:28 GMT,
(Aviation) wrote:


> Someone also pointed out my goof about "holding" your breath
> upon going from cabin (8000 ft pressure) to ambient (25-35,000
> ft pressure). In estimating how much time the average civilian
> passenger could go without TAKING a breath of good air (14,000
> ft or below), I used the HOLD your breath estimate. Assuming
> there is 3-5 minutes of mask-oxygen and one minute of "holding"
> the last breath, they've got 3-6 minutes to get down to breathable
> (14,000 ft?) air and then below. For the movie Executive Decision,
> they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
> to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?

No, the length of time you can hold your breath on the ground doesn't
help. You will outgas O2 from your blood into your lungs and then
exhale it as part of your response to the RD, because the pressure
will be so greatly reduced. You will begin using the O2 mask with a
serious deficit and you'll continue to blow off O2, even with the
mask, until you get down to the altitude where the partial pressure is
large enough. Many people can't hold their breath for a minute,
either.

Airline pilots have quick-don masks that supply O2 at a higher rate
than do the cabin masks. The cockpit O2 is a separate supply from the
cabin O2, with more O2 at higher pressure. To be blunt, it's much
more important to keep the pilots conscious, of course.

Langeweische wrote, in his article about the ValuJet accident, that no
passenger had ever been saved by cabin O2. I don't know where he got
that information, but he's pretty good about checking statements like
that.

Mary

--
Mary Shafer Retired aerospace research engineer

[khobar]

Ralph Nesbitt > wrote in message
m...
> I have no experience with "A/C Window Bullet Impact". Have seen "Spidering
> due Debris" from "uncontained engine failures. Have seen, dealt with the
> aftermath of encounters between fighter type A/C & large birds such as
> "Buzzards, Eagles, or other large carrion Feeders.

I have seen some of those. They make quite a mess.

> The "Windshields of Southern 232", a DC-9, were broken out along with
> "Catastrophic Engine Damage" by hail at altitude resulting in a
catastrophic
> incident. Many "Hail Stones of ~3" Diameter were in the cockpit when we
> arrived on scene within ~ 7 minuets of the incident. There were
substantial
> "Dents/Dings" in the rear cockpit bulkhead from the "Hail Stones".

You've probably seen the Easyjet pics:
http://www.zap16.com/Easyjet%20out%20of%20hail.htm

Paul Nixon

[C J Campbell]

"Mary Shafer" > wrote in message
|
| Langeweische wrote, in his article about the ValuJet accident, that no
| passenger had ever been saved by cabin O2. I don't know where he got
| that information, but he's pretty good about checking statements like
| that.

He is probably right. At the altitudes airliners fly the partial pressure of
oxygen is too low to be absorbed by the bloodstream. You could fill the
entire cabin with pure oxygen and everybody would still suffocate. Those
little masks are not pressurized. Even if they were, the little elastic
thingies that hold the mask on would not maintain the required pressure. The
crew, of course, have pressurized masks.

On the other hand, it would take some time for people to start dying or
suffering permanent brain damage from lack of oxygen. The frail would be
most vulnerable, but a healthy passenger would at worst just pass out until
the airliner descended into breathable air.

[Marc J. Zeitlin]

"C J Campbell" wrote;

> ....... At the altitudes airliners fly the partial pressure of
> oxygen is too low to be absorbed by the bloodstream. You could fill
the
> entire cabin with pure oxygen and everybody would still suffocate.
Those
> little masks are not pressurized.

If that were true, why would mountain climbers take little bottles of O2
with them when climbing Everest (and other 20K ft. and up mountains)?

--
Marc J. Zeitlin
http://marc.zeitlin.home.comcast.net/
http://www.cozybuilders.org/

[C J Campbell]

"Marc J. Zeitlin" > wrote in message
news:p_lJb.261887$_M.1216641@attbi_s54...
| "C J Campbell" wrote;
|
| > ....... At the altitudes airliners fly the partial pressure of
| > oxygen is too low to be absorbed by the bloodstream. You could fill
| the
| > entire cabin with pure oxygen and everybody would still suffocate.
| Those
| > little masks are not pressurized.
|
| If that were true, why would mountain climbers take little bottles of O2
| with them when climbing Everest (and other 20K ft. and up mountains)?
|

Airliners fly a lot higher than 20,000 feet. Those bottles are pressurized
and regulated as well. Climbers who use the oxygen usually only take a
breath or two when they need it. Although the masks are not very good, they
are better than the passenger masks on airliners. A lot of the oxygen is
still wasted, though. There are climbers who manage to make it up Everest
without any supplemental oxygen at all. Granted, they have had time to
acclimatize themselves, but even so it supports the idea that passengers are
not going to instantly die if the airplane depressurizes.

[John Gilmer]

"Bob Gardner" > wrote in message
news:QODIb.85072$VB2.187788@attbi_s51...
> No way. You start off at sea level, of course, and they pump the chamber
> pressure down to 25000 feet with masks on...then they do some experiments
> with a few of the pilots taking their masks off, just to show how severely
> their abilities are affected. Then comes the explosive decompression,
which
> takes the chamber from 25K back down to sea level in a second or two.

SIlly question but ...

Why would "they" pressurize the aircraft to sea level? Why not some
compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?


EMWTK

[Ralph Nesbitt]

"khobar" > wrote in message
news:LvlJb.16967$7D3.16664@fed1read02...
> Ralph Nesbitt > wrote in message
> m...
> > I have no experience with "A/C Window Bullet Impact". Have seen
"Spidering
> > due Debris" from "uncontained engine failures. Have seen, dealt with the
> > aftermath of encounters between fighter type A/C & large birds such as
> > "Buzzards, Eagles, or other large carrion Feeders.
>
> I have seen some of those. They make quite a mess.
>
> > The "Windshields of Southern 232", a DC-9, were broken out along with
> > "Catastrophic Engine Damage" by hail at altitude resulting in a
> catastrophic
> > incident. Many "Hail Stones of ~3" Diameter were in the cockpit when we
> > arrived on scene within ~ 7 minuets of the incident. There were
> substantial
> > "Dents/Dings" in the rear cockpit bulkhead from the "Hail Stones".
>
> You've probably seen the Easyjet pics:
> http://www.zap16.com/Easyjet%20out%20of%20hail.htm
>
> Paul Nixon
>
Have seen the Easy et Pic's.

Was FD/CFR/ARFF Officer in Charge/On Scene Commander at the Southern 232
incident.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[John Gilmer]

"Mike Rapoport" > wrote in message
hlink.net...
>
> "Ralph Nesbitt" > wrote in message
> gy.com...
> >
> > "Mike Rapoport" > wrote in message
> > hlink.net...
> > >
> > > "Ralph Nesbitt" > wrote in message
> > > m...
> > > > Hopefully all realize when referring to "Air Pressure" at altitude
> this
> > is
> > > > an "absolute" pressure value inside the fuselage irrespective of
> > ambient.
> > > > When referring to air pressures at ground level the pressure reading
> is
> > > > above unadjusted ambient barometric pressure.
> > > >
> > > This is incorrect, pressurization is the differential between ambient
> and
> > > cabin preasure.
> > >
> > > Mike
> > > MU-2
> > >
> > Please reconsider your statement above as it applies to pressurization
of
> > A/C cabins at altitude.
> >
> > At altitude A/C cabins are like a pressure vessel. A/C cabins are
> > pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal atmospheric
> > pressure @ 11,000' ASL, in the cabin irrespective of altitude above
> 11,000'
> > ASL.
> > Ralph Nesbitt
> > Professional FD/CFR/ARFF Type
>
> No, the cabin is not at a constant preasure above 11,000' (and the number
> that you are looking for is 8,000') unless the rate controller is set to a
> rate greater than the climb rate of the aircraft (which is never done).
If
> what you say were true then the cabin altitude would not climb with the
> airplane above 11,000' (8,000') which it clearly does. If you doubt this,
> go buy an altimeter watch and see for yourself. Or you could buy a
> pressurized airplane.

OK, I'll bite.

Just how does the psia in the cabin track the psia "ambient."
>

[Michael Williamson]

John Gilmer wrote:
>

>
> SIlly question but ...
>
> Why would "they" pressurize the aircraft to sea level? Why not some
> compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?
>

Typically, they start at whatever the local pressure altitude
happens to be (which of course may or may not be sea level, depending
on where you happen to have the chamber). Also, I've never
experienced in any altitude chamber ride a rapid REcompression
down to sea level- it strikes me as a good way to have sinus
or ear problems.

Mike

[David CL Francis]

On Fri, 2 Jan 2004 at 23:00:12 in message
>, John Gilmer
> wrote:
>SIlly question but ...
>
>Why would "they" pressurize the aircraft to sea level? Why not some
>compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?

This test, if correctly described, is irrelevant to sudden decompression
of aircraft anyway. The problem is decompression not sudden
re-compression.

In the cabin you are at, say 8,000ft. A big hole appears and you are
suddenly at the altitude the Aircraft was actually flying.
--
David CL Francis

[Mike Rapoport]

"John Gilmer" > wrote in message
...
>
> "Mike Rapoport" > wrote in message
> hlink.net...
> >
> > "Ralph Nesbitt" > wrote in message
> > gy.com...
> > >
> > > "Mike Rapoport" > wrote in message
> > > hlink.net...
> > > >
> > > > "Ralph Nesbitt" > wrote in message
> > > > m...
> > > > > Hopefully all realize when referring to "Air Pressure" at altitude
> > this
> > > is
> > > > > an "absolute" pressure value inside the fuselage irrespective of
> > > ambient.
> > > > > When referring to air pressures at ground level the pressure
reading
> > is
> > > > > above unadjusted ambient barometric pressure.
> > > > >
> > > > This is incorrect, pressurization is the differential between
ambient
> > and
> > > > cabin preasure.
> > > >
> > > > Mike
> > > > MU-2
> > > >
> > > Please reconsider your statement above as it applies to pressurization
> of
> > > A/C cabins at altitude.
> > >
> > > At altitude A/C cabins are like a pressure vessel. A/C cabins are
> > > pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal
atmospheric
> > > pressure @ 11,000' ASL, in the cabin irrespective of altitude above
> > 11,000'
> > > ASL.
> > > Ralph Nesbitt
> > > Professional FD/CFR/ARFF Type
> >
> > No, the cabin is not at a constant preasure above 11,000' (and the
number
> > that you are looking for is 8,000') unless the rate controller is set to
a
> > rate greater than the climb rate of the aircraft (which is never done).
> If
> > what you say were true then the cabin altitude would not climb with the
> > airplane above 11,000' (8,000') which it clearly does. If you doubt
this,
> > go buy an altimeter watch and see for yourself. Or you could buy a
> > pressurized airplane.
>
> OK, I'll bite.
>
> Just how does the psia in the cabin track the psia "ambient."
> >

What are you asking?

Mike
MU-2

[Gary Mishler]

"Scott M. Kozel" > wrote in message
...
> How could an SST like the Concorde get from cruising altitude down to
> 10,000 feet in 3-5 minutes?

Easy, it's called an Emergency Descent. Power to idle, spoilers/speedbrakes
deployed, maybe gear extended (depends on aircraft), then dive at redline
speed. The airplane I fly (Lear 60) it takes an initial deck angle of ~ 20
degrees nose down to obtain redline, then ~ 10-12 degrees to hold it there.

We practice it every time we have a simulator check. Never takes more than
3 mins to get from FL450 to 10,000 ft.

Mish

[running with scissors]

"Marco Leon" <mleon(at)optonline.net> wrote in message >...
> "Aviation" > wrote in message
> u...
> >
> > The second Hollywood inspired question comes from Executive
> > Decision (1996). The main character is taking flying lessons
> > in a single prop 2-seater plane and lands. The plane is still
> > running (on the ground) and his instructor says, 'I think
> > you're ready to solo' and gets out. The main character starts
> > to taxi and then other non-flying plot developments happen.
> > I was wondering if taking your FIRST solo flight is that simple.
> >
> > The location in the film in Washington, DC but I figure all
> > US flying is FAA regulated. Wouldn't the first time soloist
> > have to fill out some forms, file a flight plan with the
> > airport and maybe even do a complete pre-flight check on the
> > aircraft? Is the simplified movie solo flight completely
> > bogus or could it happen that way?
> >
>
> Yes as mentioned by others, the first solo is usually that easy (with a
> couple of signatures in your logbook)
>
> The plane in Executive Decision was a Bonanza that has 4 or 6 seats (model
> F33 or A/B36 respectively. Not sure which was in the movie) and Kurt Russell
> is a pilot in real life. That plane could have very well been his own ;) Or
> at least he may have been flying it during the filming. Anyone know??
>
> Marco
>

CE-421

[running with scissors]

"Marco Leon" <mleon(at)optonline.net> wrote in message >...
> I was hoping this medium would be faster than renting the flick. Besides,
> many publically accessible information regarding celebrities are ususally
> cryptic. Ever seen a privately-owned plane registered under a corporation?
>

yup. regularly

[running with scissors]

Dr. George O. Bizzigotti > wrote in message >...
> On Tue, 30 Dec 2003 19:43:55 -0800, "G.R. Patterson III"
> > wrote:
>
> >Aviation wrote:
>
> >> On the one hand, passengers need to get denser air to breathe
> >> but large aircraft have oxygen masks that drop down.
>
> [snip]
>
> >As for your ears, they're already toast. The pressure just dropped
> >from the pressure at 8,000' to that at cruise altitude in a few seconds.
>
> Based on what others have written about chamber simulations, it would
> appear that irreversible ear damage (which is what I would infer as
> being "toast") is not an inevitable consequence, although. I've no
> doubt that the sensation from any reversible consequences is not
> always pleasant .
>
> >Basically, the pilots need to get their masks on and get the plane down below
> >25,000' as rapidly as it can possibly be done. The descent to 10,000' can be made
> >a little more leisurely, but not much - there's always someone in the cattle
> >section who panicked and isn't wearing a mask.
>
> One aspect that I have not seen addressed in this thread is the fact
> that most oxygen systems can provide supplemental oxygen for a few
> minutes only (I dimly recall figures like 3-5 minutes, but that may be
> inaccurate). The pilots also need to get down to 10,000 feet within
> that time before everyone's oxygen generators run out.
>
> Regards,

nope. supplemental oxygen depends on the capacity of the resevoir, the
flow, the delivery system in use and of course the demands on this
(load) the requirements are in the FAR's.

23.1441 thru 23.1449
25.1441 thru 25.1449
121.327 thru 121.337
125.219
135.89 thru 135.91
135.157

[running with scissors]

(One's Too Many) wrote in message >...
> "Bob Gardner" > wrote in message news:<d0oIb.79631$VB2.161783@attbi_s51>...
> > I just measured my Kraft 8oz container of grated Parmesan...2 3/4 inches.
> > Close enough?
> >
> > Bob Gardner
>
> Well, maybe close enough. That stuff in the Kraft can might qualify as
> some kind of 'Parmesan-like substance', but I'd hestiate to call it
> real Parmesan cheese. I'd only consider putting it on my pasta if I'd
> had way too much wine to drink beforehand.
>

"cheese flavoured product" is the catch all there !

[running with scissors]

"Scott M. Kozel" > wrote in message >...
> Dr. George O. Bizzigotti > wrote:
> >
> > "G.R. Patterson III" > wrote:
> >
> > >Basically, the pilots need to get their masks on and get the plane down below
> > >25,000' as rapidly as it can possibly be done. The descent to 10,000' can be made
> > >a little more leisurely, but not much - there's always someone in the cattle
> > >section who panicked and isn't wearing a mask.
> >
> > One aspect that I have not seen addressed in this thread is the fact
> > that most oxygen systems can provide supplemental oxygen for a few
> > minutes only (I dimly recall figures like 3-5 minutes, but that may be
> > inaccurate). The pilots also need to get down to 10,000 feet within
> > that time before everyone's oxygen generators run out.
>
> How could an SST like the Concorde get from cruising altitude down to
> 10,000 feet in 3-5 minutes?


emergency descent, throttles set, dirty up, hold pitch. regularly
practiced procedure. the express elevator down.

[running with scissors]

"John Gaquin" > wrote in message >...
> "G.R. Patterson III" > wrote in message
> >
> > If the aircraft is much above 25,000', the masks will do little good. You
> need
> > a pressure mask to survive long at (for example) 35,000'. Those used by
> the
> > airlines for passengers are not good enough for that.
>
> Passenger masks generally only need to provide sustenance for a couple of
> minutes.
>
> > > ....the jet would have to go from let's say 30000 feet to 5000 feet in
> > > 30-45 seconds. My ears would explode.)
> >
> > Basically, the pilots need to get their masks on and get the plane down
> below
> > 25,000' as rapidly as it can possibly be done. The descent to 10,000' can
> be made
> > a little more leisurely, but not much - there's always someone in the
> cattle
> > section who panicked and isn't wearing a mask. If that's one of the flight
> > attendants, you're really in trouble.
>
> Ten thousand is where supplemental O2 is no longer legally required. In
> reality, you're back in survivable atmosphere, for most people, at about
> 14,000 or so. Emergency descent procedures are predicated on descending
> from cruise altitude to 10,000 MSL (or an altitude where you can maintain a
> cabin alt of 10K) as rapidly as is safely possible. As a practical matter,
> you won't be descending at much over 12-15 thousand f/m or so, so the
> descent will take a minute and a half or more.


FAR 91.211
Supplemental oxygen.
(a) General. No person may operate a civil aircraft of U.S. registry -
(1) At cabin pressure altitudes above 12,500 feet (MSL) up to and
including 14,000 feet (MSL) unless the required minimum flight crew is
provided with and uses supplemental oxygen for that part of the flight
at those altitudes that is of more than 30 minutes duration;
(2) At cabin pressure altitudes above 14,000 feet (MSL) unless the
required minimum flight crew is provided with and uses supplemental
oxygen during the entire flight time at those altitudes; and
(3) At cabin pressure altitudes above 15,000 feet (MSL) unless each
occupant of the aircraft is provided with supplemental oxygen.
(b) Pressurized cabin aircraft.
(1) No person may operate a civil aircraft of U.S. registry with a
pressurized cabin -
(i) At flight altitudes above flight level 250 unless at least a
10-minute supply of supplemental oxygen, in addition to any oxygen
required to satisfy paragraph (a) of this section, is available for
each occupant of the aircraft for use in the event that a descent is
necessitated by loss of cabin pressurization; and
(ii) At flight altitudes above flight level 350 unless one pilot at
the controls of the airplane is wearing and using an oxygen mask that
is secured and sealed and that either supplies oxygen at all times or
automatically supplies oxygen whenever the cabin pressure altitude of
the airplane exceeds 14,000 feet (MSL), except that the one pilot need
not wear and use an oxygen mask while at or below flight level 410 if
there are two pilots at the controls and each pilot has a
quick-donning type of oxygen mask that can be placed on the face with
one hand from the ready position within 5 seconds, supplying oxygen
and properly secured and sealed.
(2) Notwithstanding paragraph (b)(1)(ii) of this section, if for any
reason at any time it is necessary for one pilot to leave the controls
of the aircraft when operating at flight altitudes above flight level
350, the remaining pilot at the controls shall put on and use an
oxygen mask until the other pilot has returned to that crewmember's
station.

135.89
ilot requirements: Use of oxygen.
(a) Unpressurized aircraft. Each pilot of an unpressurized aircraft
shall use oxygen continuously when flying -
(1) At altitudes above 10,000 feet through 12,000 feet MSL for that
part of the flight at those altitudes that is of more than 30 minutes
duration; and
(2) Above 12,000 feet MSL.
(b) Pressurized aircraft.
(1) Whenever a pressurized aircraft is operated with the cabin
pressure altitude more than 10,000 feet MSL, each pilot shall comply
with paragraph (a) of this section.
(2) Whenever a pressurized aircraft is operated at altitudes above
25,000 feet through 35,000 feet MSL, unless each pilot has an approved
quick donning type oxygen mask -
(i) At least one pilot at the controls shall wear, secured and sealed,
an oxygen mask that either supplies oxygen at all times or
automatically supplies oxygen whenever the cabin pressure altitude
exceeds 12,000 feet MSL; and
(ii) During that flight, each other pilot on flight deck duty shall
have an oxygen mask, connected to an oxygen supply, located so as to
allow immediate placing of the mask on the pilot's face sealed and
secured for use.
(3) Whenever a pressurized aircraft is operated at altitudes above
35,000 feet MSL, at least one pilot at the controls shall wear,
secured and sealed, an oxygen mask required by paragraph (b)(2)(i) of
this section.
(4) If one pilot leaves a pilot duty station of an aircraft when
operating at altitudes above 25,000 feet MSL, the remaining pilot at
the controls shall put on and use an approved oxygen mask until the
other pilot returns to the pilot duty station of the aircraft.

[running with scissors]

"C J Campbell" > wrote in message >...
> "Ron Natalie" > wrote in message
> m...
> |
> | "C J Campbell" > wrote in message
> ...
> |
> | > We do not really know any such thing. If the passenger is bigger than
> the
> | > window he simply cannot be pulled through it any more than he can sucked
> up
> | > through a vacuum cleaner hose.
> | >
> | Passengers are pretty flexible. Some might plug up the hole, others
> will
> | go through holes that looked like they ought not to fit through.
> |
>
> The windows are surprisingly large, too. I have no doubt that a small person
> could get through one, especially if his seatbelt is not properly fastened.
> However, you are not going to lose a whole planeload of passengers this way.
> Given a choice, I would shoot a hijacker with the off chance of killing an
> innocent bystander rather than allow the hijacker to drive the plane into a
> crowded building.


ok.. interesting scenario. but what would be the option if the
hijacker was a midget ??

[Michael Williamson]

Mike Rapoport wrote:
> "John Gilmer" > wrote in message
> ...
>
>>"Mike Rapoport" > wrote in message
hlink.net...
>>
>>>"Ralph Nesbitt" > wrote in message
gy.com...
>>>
>>>>
>>>>At altitude A/C cabins are like a pressure vessel. A/C cabins are
>>>>pressurized to maintain ~ 12 PSI Gauge, ~ the same as normal
>>>
> atmospheric
>
>>>>pressure @ 11,000' ASL, in the cabin irrespective of altitude above
>>>
>>>11,000'
>>>
>>>>ASL.
>>>>Ralph Nesbitt
>>>>Professional FD/CFR/ARFF Type
>>>
>>>No, the cabin is not at a constant preasure above 11,000' (and the
>>
> number
>
>>>that you are looking for is 8,000') unless the rate controller is set to
>>
> a
>
>>>rate greater than the climb rate of the aircraft (which is never done).
>>
>>If
>>
>>>what you say were true then the cabin altitude would not climb with the
>>>airplane above 11,000' (8,000') which it clearly does. If you doubt
>>
> this,
>
>>>go buy an altimeter watch and see for yourself. Or you could buy a
>>>pressurized airplane.
>>
>>OK, I'll bite.
>>
>>Just how does the psia in the cabin track the psia "ambient."
>>
>
> What are you asking?
>
> Mike

The comment was made that the pressure inside the cabin is not
necessarily constant above a certain altitude, unless certain
cabin rate settings were made, possibly leading to confusion
over cabin altitude vs. actual aircraft altitude.

It is a simplification to say that cabin altitude
is constant above a given aircraft altitude. In fact, the
cabin altitude will move toward a certain altitude (8,000'
in most cases, it seems) as set by the cabin pressurization
controller (or any of its several other names), IF the
outside pressure altitude is higher than the cabin altitude.
That is to say that if you take off from sea level and climb
to 10,000', the cabin altitude will steadily climb, at a rate
set by the cabin pressure controller, toward 8,000'. If you
were to level off at 5,000' and stay there long enough for
the cabin pressure to catch up, it will maintain 5,000'
until the aircraft begins to climb again, at which it will
again climb at the set rate until it reaches either the set
cabin altitude or the actual ambient pressure altitude. So
the cabin pressure can be below 8,000' (or whatever the
set altitude is) at actual altitudes above the set altitude,
but will be moving toward the set altitude in that case.

Note that cabin altitude cannot be maintained ABOVE the
actual pressure altitude, as air is continually pumped into
the cabin by the bleed air system, and is let out (or leaks
out) to maintain the set altitude or rate of change. If
you descend quickly enough, you may temporarily get a
cabin altitude above ambient, but air will not exit the
aircraft (outside pressure would prevent any air from
leaving through the outflow valve, and in some cases a
safety valve may automatically open to allow air to flow
INTO the aircraft, relieving the negative pressure
differential) and air flowing into the cabin will tend
to increase pressure rapidly until equilibrium is reached.

Having attained the pressure set by the controller,
the system will typically attempt to maintain that
pressure altitude until it is reset to another
altitude, although it may not always be able to.
Descents with low engine power may result in not
airflow into the cabin to match the outflow, due
either to the controller not closing the outflow
valve fast or far enough, or due to leaks in the
airframe letting more air out than the system
can pump in. Also, the cabin controller will
typically not allow a pressure differential above
a certain limit- too much pressure differential
stresses the fuselage. The controller will open
the outflow valve to maintain that maximum
differential, so at that point, if the aircraft
climbs then the cabin altitude will increase as
well.

Prior to or during the descent, the cabin
pressure controller would normally be set to
the field pressure altitude (which is normally
below the cabin altitude during cruise, but
this may not always be the case). The
controller will then begin to decrease the
cabin altitude, again at the set rate. This
prevents rapid pressure changes as the
aircraft descends through the cruise cabin
altitude and is more easier on the passengers
and crew.

Long and convoluted enough for you?

Mike
EC-130H Compass Call
"In Jam, no one can hear you scream"

[running with scissors]

"Ron Natalie" > wrote in message >...
> "C J Campbell" > wrote in message ...
>
> > We do not really know any such thing. If the passenger is bigger than the
> > window he simply cannot be pulled through it any more than he can sucked up
> > through a vacuum cleaner hose.
> >
> Passengers are pretty flexible. Some might plug up the hole, others will
> go through holes that looked like they ought not to fit through.

a midget will

[running with scissors]

(Aviation) wrote in message >...
> Thank you, everyone, for providing lots of helpful answers and info.
>
> Even with slightly inaccurate info (2-seater; 6-seater), I guess
> the second Q was easy:
> >>Is the simplified movie solo flight completely
> >> bogus or could it happen that way?
> >
> >The basic answer is "more or less".
>
> The answers to the first Q, being more tecnically compicated, leave
> me asking for a few clarifications. That was about what REALLY happens
> when a large pressurized aircraft, e.g., a 747, explosively or
> catastrophically decompresses at high (25000+ feet) altitude.
>
> Ron Natalie ) wrote:
> >> On the one hand, passengers need to get denser air to breathe
> >> but large aircraft have oxygen masks that drop down.
> >
> >The pilots initiate the dive for the reasons you suggest. While
> >supplemental oxygen helps, it's still better to get down to a >reasonable altitude. They presmably notify ATC while they are doing
> >this that there is an emergency in progress.
>
> So, other than alarms or other signals, there is NOTHING AUTOMATIC
> that puts the aircraft into rapid descent. Pilots have to respond
> to the signals (explosion, screams from the cabin, meters in their
> cockpit, their own ears popping, flashing lights, bells and whistles,
> etc.) and initiate the dive MANUALLY. For well trained pilots this
> would take, what, only a few seconds at most? Do they put their oxygen
> masks on FIRST or start the dive first?
>
> In some movies, the pilots are often unconscious, slumped over the
> controls (wedging the 'steering wheel' / joystick full forward) as
> the hero struggles to pull them out of the way and get out of the
> dive. It sounds like a pilot, if not alert or in good health, could
> actually lose consciousness from hypoxia under these conditions, so
> maybe those kinds of movie scenes are ALMOST believable?
>
> (This assumes worst case total decompression. It was pointed out
> by Mike Rapoport ) that the cabin might
> not even go to ambient pressure if the hole isn't too big and the
> outflow valves close down and the engines keep pumping air into the
> cabin.)
>
> Someone also pointed out my goof about "holding" your breath
> upon going from cabin (8000 ft pressure) to ambient (25-35,000
> ft pressure). In estimating how much time the average civilian
> passenger could go without TAKING a breath of good air (14,000
> ft or below), I used the HOLD your breath estimate. Assuming
> there is 3-5 minutes of mask-oxygen and one minute of "holding"
> the last breath, they've got 3-6 minutes to get down to breathable
> (14,000 ft?) air and then below. For the movie Executive Decision,
> they were cruising at 39,000 ft. so they'd have to dive 25,000 ft
> to 14,000 ft in 5 minutes, 5,000 ft/minute, average. Doable?

nope a person cannot simply hold ones breath. the pressure
differential between the airway cavity and the outside of the body
makes this impossible. in addition, a body of air expands and
contracts under pressure.

if anyone here is a certified diver they will be aware of compression
of air in the human body at depth (and the effects on ascent and
descent), and conversely the expansion of air at altitide.

[running with scissors]

"John Gilmer" > wrote in message >...
> "Bob Gardner" > wrote in message
> news:QODIb.85072$VB2.187788@attbi_s51...
> > No way. You start off at sea level, of course, and they pump the chamber
> > pressure down to 25000 feet with masks on...then they do some experiments
> > with a few of the pilots taking their masks off, just to show how severely
> > their abilities are affected. Then comes the explosive decompression,
> which
> > takes the chamber from 25K back down to sea level in a second or two.
>
> SIlly question but ...
>
> Why would "they" pressurize the aircraft to sea level? Why not some
> compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?
>
>
> EMWTK

"they" dont. cabin pressurization is normally at 8000ft though crew
may elect to use different cabin pressures under certain circumstances
(eg medevac operations where pressurization is a factor)

[running with scissors]

Michael Williamson > wrote in message >...
> John Gilmer wrote:
> >
>
> >
> > SIlly question but ...
> >
> > Why would "they" pressurize the aircraft to sea level? Why not some
> > compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?
> >
>
> Typically, they start at whatever the local pressure altitude
> happens to be (which of course may or may not be sea level, depending
> on where you happen to have the chamber). Also, I've never
> experienced in any altitude chamber ride a rapid REcompression
> down to sea level- it strikes me as a good way to have sinus
> or ear problems.
>
> Mike


nope. when the doors on an aircraft are shut the pressure is ambient.
thats it. when bleed air pressures the cabin its noramlly to about
8000ft.

[khobar]

Michael Williamson > wrote in message
...

> Note that cabin altitude cannot be maintained ABOVE the
> actual pressure altitude, as air is continually pumped into
> the cabin by the bleed air system, and is let out (or leaks
> out) to maintain the set altitude or rate of change. If
> you descend quickly enough, you may temporarily get a
> cabin altitude above ambient, but air will not exit the
> aircraft (outside pressure would prevent any air from
> leaving through the outflow valve, and in some cases a
> safety valve may automatically open to allow air to flow
> INTO the aircraft, relieving the negative pressure
> differential) and air flowing into the cabin will tend
> to increase pressure rapidly until equilibrium is reached.

http://www.b737.org.uk/pressurisation.htm has some good information.

Paul Nixon

[Gary Mishler]

"running with scissors" > wrote in
message om...

> "they" dont. cabin pressurization is normally at 8000ft though crew
> may elect to use different cabin pressures under certain circumstances

Actually, it depends on the aircraft. Aircraft are certified to certain
"differential pressures" which is the difference between in the inside cabin
pressure and the outside ambient air pressure. An airframe must be designed
to handle the differential pressure required to maintain acceptable cabin
altitude up to the max flight level the aircraft is certified to.

As an example, the King Air I fly has a normal differential pressure of 6.6
psid. This provides for a cabin altitude of 2,700 up to 20,000 cruise
altitude, an 8,700 foot cabin altitude at 31,000 cruise altitude, and a
10,200 foot cabin altitude at 35,000 cruise altitude.

In contrast, the Lear 60 I fly has a normal psid of 9.5 (9.7 max) which
typically results in a cabin altitudes of around aprox 6,500 up in the
40,000 ish cruise altitudes.

[Jack Davis]

On Tue, 30 Dec 2003 22:12:24 GMT, "Bob Gardner" >
wrote:

> I have no direct knowledge of how big an airliner
>outflow valve is, but I am going to guess three inches in diameter

That would not be a good guess! ;) The main outflow valve on a 737 is
much larger than that.

-J


-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
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[Michael Williamson]

running with scissors wrote:
> Michael Williamson > wrote in message >...
>
>>John Gilmer wrote:
>>
>>
>>
>>>SIlly question but ...
>>>
>>>Why would "they" pressurize the aircraft to sea level? Why not some
>>>compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?
>>>
>>
>> Typically, they start at whatever the local pressure altitude
>>happens to be (which of course may or may not be sea level, depending
>>on where you happen to have the chamber). Also, I've never
>>experienced in any altitude chamber ride a rapid REcompression
>>down to sea level- it strikes me as a good way to have sinus
>>or ear problems.
>>
>>Mike
>
>
>
> nope. when the doors on an aircraft are shut the pressure is ambient.
> thats it. when bleed air pressures the cabin its noramlly to about
> 8000ft.

While the final (steady state) pressure of the aircraft
(as determined by the cabin pressurization controller) will end
up at its cruise setting, the aircraft is pressurized from
takeoff and the cabin altitude will typically climb slowly
toward its set value (about 8,000' in this case) rather than
follow ambient- the pressurization system is indeed pressurizing
the aircraft its initial field elevation up to the cruise
pressurization setting.

In addition, my above response was poorly worded and I actually
was commenting on the pressurization of the altitude chamber- which
begins at whatever the ambient pressure happens to be. My bad for
not reading the question closely enough.

Mike

[Ron Natalie]

"Gary Mishler" > wrote in message news:eBoKb.745162$HS4.5776347@attbi_s01...
> "running with scissors" > wrote in
> message om...
>
> > "they" dont. cabin pressurization is normally at 8000ft though crew
> > may elect to use different cabin pressures under certain circumstances
>
> Actually, it depends on the aircraft. Aircraft are certified to certain
> "differential pressures" which is the difference between in the inside cabin
> pressure and the outside ambient air pressure.

We were talking about transport aircraft. US certificated transport aircraft
must keep the cabin altitude below 8000'.

[khobar]

running with scissors > wrote in
message om...
> "John Gilmer" > wrote in message
>...
> > "Bob Gardner" > wrote in message
> > news:QODIb.85072$VB2.187788@attbi_s51...
> > > No way. You start off at sea level, of course, and they pump the
chamber
> > > pressure down to 25000 feet with masks on...then they do some
experiments
> > > with a few of the pilots taking their masks off, just to show how
severely
> > > their abilities are affected. Then comes the explosive decompression,
> > which
> > > takes the chamber from 25K back down to sea level in a second or two.
> >
> > SIlly question but ...
> >
> > Why would "they" pressurize the aircraft to sea level? Why not some
> > compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?
> >
> >
> > EMWTK
>
> "they" dont. cabin pressurization is normally at 8000ft though crew
> may elect to use different cabin pressures under certain circumstances
> (eg medevac operations where pressurization is a factor)

Sec. 25.1 Applicability.

(a) This part prescribes airworthiness standards for the issue of type
certificates, and changes to those certificates, for transport category
airplanes.
http://www.astech-engineering.com/systems/avionics/aircraft/faapart25d.html#
Pressurization

Sec. 25.841 Pressurized cabins.

"(a) Pressurized cabins and compartments to be occupied must be equipped to
provide a cabin pressure altitude of not more than 8,000 feet at the maximum
operating altitude of the airplane under normal operating conditions."

Transport category:

* All jets with 10 or more seats or greater than 12,500lb Maximum
Takeoff Weight.
* All propeller driven airplanes with greater than 19 seats or greater
than 19,000lb Maximum Takeoff Weight.


Obviously the rule would not normlly apply to Medivac operations.

HTH,

Paul Nixon

[Tom Sixkiller]

"running with scissors" > wrote in
message m...
> "C J Campbell" > wrote in message
>...
> > "Ron Natalie" > wrote in message
> > m...
> > |
> > | "C J Campbell" > wrote in
message
> > ...
> > |
> > | > We do not really know any such thing. If the passenger is bigger
than
> > the
> > | > window he simply cannot be pulled through it any more than he can
sucked
> > up
> > | > through a vacuum cleaner hose.
> > | >
> > | Passengers are pretty flexible. Some might plug up the hole, others
> > will
> > | go through holes that looked like they ought not to fit through.
> > |
> >
> > The windows are surprisingly large, too. I have no doubt that a small
person
> > could get through one, especially if his seatbelt is not properly
fastened.
> > However, you are not going to lose a whole planeload of passengers this
way.
> > Given a choice, I would shoot a hijacker with the off chance of killing
an
> > innocent bystander rather than allow the hijacker to drive the plane
into a
> > crowded building.
>
>
> ok.. interesting scenario. but what would be the option if the
> hijacker was a midget ??

Shoot him with a .22?

[John Gaquin]

"running with scissors" > wrote in
message >
> FAR 91.211
> Supplemental oxygen.

????

[Gary Mishler]

"Ron Natalie" > wrote in message
m...
>
> "Gary Mishler" > wrote in message
news:eBoKb.745162$HS4.5776347@attbi_s01...
> > "running with scissors" > wrote
in
> > message om...
> >
> > > "they" dont. cabin pressurization is normally at 8000ft though crew
> > > may elect to use different cabin pressures under certain circumstances
> >
> > Actually, it depends on the aircraft. Aircraft are certified to certain
> > "differential pressures" which is the difference between in the inside
cabin
> > pressure and the outside ambient air pressure.
>
> We were talking about transport aircraft. US certificated transport
aircraft
> must keep the cabin altitude below 8000'.

Yup, I know. The Lear 60 is a transport category aircraft, certified under
Part 25, and it's cabin is normally around +/- 6,500ft. Previous poster
said cabin pressure is normally *at* 8,000 and I was just pointing out that
it depends on the aircraft.

Manufactures of transport category corporate jets seem to take pride in
pointing out to potential customers that their jet can maintain a lower
cabin altitude at cruise than the competitors, which all depends on the
certificated max psid.

[Dennis O'Connor]

Yup, but the butterfly is not necessarily all the way open at cruise
altitude... Anyway, us ga airplane folks generally don't appreciate how
much air flow the compressors can deliver to the cabin, especially if you by
pass the cooler - any idea what the cabin temperature go up to if direct
feed off the compressor was delivered to the cabin?... Might be a good
behavior modification tool...
Denny
"Jack Davis" > wrote > That would not be a good
guess! ;) The main outflow valve on a 737 is
> much larger than that.

[running with scissors]

"Gary Mishler" > wrote in message news:<eBoKb.745162$HS4.5776347@attbi_s01>...
> "running with scissors" > wrote in
> message om...
>
> > "they" dont. cabin pressurization is normally at 8000ft though crew
> > may elect to use different cabin pressures under certain circumstances
>
> Actually, it depends on the aircraft.


uh huh. i know it does. though if i posted an exact figure for a
specific aircraft type, then a whole flood of posts saying i am wrong
because "xx" type is pressurized to "yy"




Aircraft are certified to certain
> "differential pressures" which is the difference between in the inside cabin
> pressure and the outside ambient air pressure. An airframe must be designed
> to handle the differential pressure required to maintain acceptable cabin
> altitude up to the max flight level the aircraft is certified to.
>
> As an example, the King Air I fly has a normal differential pressure of 6.6
> psid. This provides for a cabin altitude of 2,700 up to 20,000 cruise
> altitude, an 8,700 foot cabin altitude at 31,000 cruise altitude, and a
> 10,200 foot cabin altitude at 35,000 cruise altitude.
>
> In contrast, the Lear 60 I fly has a normal psid of 9.5 (9.7 max) which
> typically results in a cabin altitudes of around aprox 6,500 up in the
> 40,000 ish cruise altitudes.

[running with scissors]

Michael Williamson > wrote in message >...
> running with scissors wrote:
> > Michael Williamson > wrote in message >...
> >
> >>John Gilmer wrote:
> >>
> >>
> >>
> >>>SIlly question but ...
> >>>
> >>>Why would "they" pressurize the aircraft to sea level? Why not some
> >>>compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?
> >>>
> >>
> >> Typically, they start at whatever the local pressure altitude
> >>happens to be (which of course may or may not be sea level, depending
> >>on where you happen to have the chamber). Also, I've never
> >>experienced in any altitude chamber ride a rapid REcompression
> >>down to sea level- it strikes me as a good way to have sinus
> >>or ear problems.
> >>
> >>Mike
> >
> >
> >
> > nope. when the doors on an aircraft are shut the pressure is ambient.
> > thats it. when bleed air pressures the cabin its noramlly to about
> > 8000ft.
>
> While the final (steady state) pressure of the aircraft
> (as determined by the cabin pressurization controller) will end
> up at its cruise setting, the aircraft is pressurized from
> takeoff and the cabin altitude will typically climb slowly
> toward its set value (about 8,000' in this case) rather than
> follow ambient- the pressurization system is indeed pressurizing
> the aircraft its initial field elevation up to the cruise
> pressurization setting.
>
> In addition, my above response was poorly worded and I actually
> was commenting on the pressurization of the altitude chamber- which
> begins at whatever the ambient pressure happens to be. My bad for
> not reading the question closely enough.
>
> Mike


ditto, my bad for not reading closely. although you used the words
cabin pressurization, you did use the word chamber too !

[running with scissors]

"khobar" > wrote in message news:<W_qKb.17919$7D3.14891@fed1read02>...
> running with scissors > wrote in
> message om...
> > "John Gilmer" > wrote in message
> >...
> > > "Bob Gardner" > wrote in message
> > > news:QODIb.85072$VB2.187788@attbi_s51...
> > > > No way. You start off at sea level, of course, and they pump the
> chamber
> > > > pressure down to 25000 feet with masks on...then they do some
> experiments
> > > > with a few of the pilots taking their masks off, just to show how
> severely
> > > > their abilities are affected. Then comes the explosive decompression,
> which
> > > > takes the chamber from 25K back down to sea level in a second or two.
> > >
> > > SIlly question but ...
> > >
> > > Why would "they" pressurize the aircraft to sea level? Why not some
> > > compromise "pressure" like that equivalent to, say, 6,000 or 8,000 feet?
> > >
> > >
> > > EMWTK
> >
> > "they" dont. cabin pressurization is normally at 8000ft though crew
> > may elect to use different cabin pressures under certain circumstances
> > (eg medevac operations where pressurization is a factor)
>
> Sec. 25.1 Applicability.
>
> (a) This part prescribes airworthiness standards for the issue of type
> certificates, and changes to those certificates, for transport category
> airplanes.
> http://www.astech-engineering.com/systems/avionics/aircraft/faapart25d.html#
> Pressurization
>
> Sec. 25.841 Pressurized cabins.
>
> "(a) Pressurized cabins and compartments to be occupied must be equipped to
> provide a cabin pressure altitude of not more than 8,000 feet at the maximum
> operating altitude of the airplane under normal operating conditions."
>
> Transport category:
>
> * All jets with 10 or more seats or greater than 12,500lb Maximum
> Takeoff Weight.
> * All propeller driven airplanes with greater than 19 seats or greater
> than 19,000lb Maximum Takeoff Weight.
>
>
> Obviously the rule would not normlly apply to Medivac operations.
>
> HTH,
>
> Paul Nixon

medevac ops are not exempt. though under certain medical conditions
the cabin my not be pressurized or pressurized to a lower altitude.
nitrogen narcosis is one condition that springs to mind.

[running with scissors]

"Tom Sixkiller" > wrote in message >...
> "running with scissors" > wrote in
> message m...
> > "C J Campbell" > wrote in message
> >...
> > > "Ron Natalie" > wrote in message
> > > m...
> > > |
> > > | "C J Campbell" > wrote in
> message
> ...
> > > |
> > > | > We do not really know any such thing. If the passenger is bigger
> than
> the
> > > | > window he simply cannot be pulled through it any more than he can
> sucked
> up
> > > | > through a vacuum cleaner hose.
> > > | >
> > > | Passengers are pretty flexible. Some might plug up the hole, others
> will
> > > | go through holes that looked like they ought not to fit through.
> > > |
> > >
> > > The windows are surprisingly large, too. I have no doubt that a small
> person
> > > could get through one, especially if his seatbelt is not properly
> fastened.
> > > However, you are not going to lose a whole planeload of passengers this
> way.
> > > Given a choice, I would shoot a hijacker with the off chance of killing
> an
> > > innocent bystander rather than allow the hijacker to drive the plane
> into a
> > > crowded building.
> >
> >
> > ok.. interesting scenario. but what would be the option if the
> > hijacker was a midget ??
>
> Shoot him with a .22?


lol

[khobar]

running with scissors > wrote in
message om...
> "khobar" > wrote in message
news:<W_qKb.17919$7D3.14891@fed1read02>...
> > running with scissors > wrote
in
> > message om...
> > > "John Gilmer" > wrote in message
> > >...
> > > > "Bob Gardner" > wrote in message
> > > > news:QODIb.85072$VB2.187788@attbi_s51...
> > > > > No way. You start off at sea level, of course, and they pump the
> > chamber
> > > > > pressure down to 25000 feet with masks on...then they do some
> > experiments
> > > > > with a few of the pilots taking their masks off, just to show how
> > severely
> > > > > their abilities are affected. Then comes the explosive
decompression,
> > which
> > > > > takes the chamber from 25K back down to sea level in a second or
two.
> > > >
> > > > SIlly question but ...
> > > >
> > > > Why would "they" pressurize the aircraft to sea level? Why not
some
> > > > compromise "pressure" like that equivalent to, say, 6,000 or 8,000
feet?
> > > >
> > > >
> > > > EMWTK
> > >
> > > "they" dont. cabin pressurization is normally at 8000ft though crew
> > > may elect to use different cabin pressures under certain circumstances
> > > (eg medevac operations where pressurization is a factor)
> >
> > Sec. 25.1 Applicability.
> >
> > (a) This part prescribes airworthiness standards for the issue of type
> > certificates, and changes to those certificates, for transport category
> > airplanes.
> >
http://www.astech-engineering.com/systems/avionics/aircraft/faapart25d.html#
> > Pressurization
> >
> > Sec. 25.841 Pressurized cabins.
> >
> > "(a) Pressurized cabins and compartments to be occupied must be equipped
to
> > provide a cabin pressure altitude of not more than 8,000 feet at the
maximum
> > operating altitude of the airplane under normal operating conditions."
> >
> > Transport category:
> >
> > * All jets with 10 or more seats or greater than 12,500lb Maximum
> > Takeoff Weight.
> > * All propeller driven airplanes with greater than 19 seats or
greater
> > than 19,000lb Maximum Takeoff Weight.
> >
> >
> > Obviously the rule would not normlly apply to Medivac operations.
> >
> > HTH,
> >
> > Paul Nixon
>
> medevac ops are not exempt. though under certain medical conditions
> the cabin my not be pressurized or pressurized to a lower altitude.
> nitrogen narcosis is one condition that springs to mind.

I was thinking about medivac helicopters. Dunno why since medivac goes
beyond helicopter operations. Oh well...

Paul Nixon

[running with scissors]

"Gary Mishler" > wrote in message news:<N3yKb.764106$Fm2.730963@attbi_s04>...
> "Ron Natalie" > wrote in message
> m...
> >
> > "Gary Mishler" > wrote in message
> news:eBoKb.745162$HS4.5776347@attbi_s01...
> > > "running with scissors" > wrote
> in
> > > message om...
> > >
> > > > "they" dont. cabin pressurization is normally at 8000ft though crew
> > > > may elect to use different cabin pressures under certain circumstances
> > >
> > > Actually, it depends on the aircraft. Aircraft are certified to certain
> > > "differential pressures" which is the difference between in the inside
> cabin
> > > pressure and the outside ambient air pressure.
> >
> > We were talking about transport aircraft. US certificated transport
> aircraft
> > must keep the cabin altitude below 8000'.
>
> Yup, I know. The Lear 60 is a transport category aircraft, certified under
> Part 25, and it's cabin is normally around +/- 6,500ft. Previous poster
> said cabin pressure is normally *at* 8,000 and I was just pointing out that
> it depends on the aircraft.
>
> Manufactures of transport category corporate jets seem to take pride in
> pointing out to potential customers that their jet can maintain a lower
> cabin altitude at cruise than the competitors, which all depends on the
> certificated max psid.


christ on a bike. i knew this would happen.

i stated "normally at 8,000ft", of course there are variations in
type, SOP and so on. i really didnt want to spend hours typing out a
list types and representative pressurization variations or a list of
SOP's for various operators of various types as either way it is going
to depend on what is set on the selector. say 8,000ft and someone will
say "we fly at 7,500".

the answer is in the FAR's.

[Gary Mishler]

"running with scissors" > wrote in
message m...

> > > > > "they" dont. cabin pressurization is normally at 8000ft ...

I noted:
> > > > Actually, it depends on the aircraft...

< Explanation of pressurization certification, that some may find
informative, snipped. >

An anonomyus person calling himself "running with scissors" replied with:

> christ on a bike. i knew this would happen.
>
> i stated "normally at 8,000ft", of course there are variations in
> type, SOP and so on. i really didnt want to spend hours typing out a
> list types and representative pressurization variations or a list of
> SOP's for various operators of various types as either way it is going
> to depend on what is set on the selector. say 8,000ft and someone will
> say "we fly at 7,500".
>
> the answer is in the FAR's.


Whoa big fella, cool your jets there.

> the answer is in the FAR's.

Indeed it is. If someone offering further information for the benefit of
others in the NG was going to get your gander up so high, you could have
said something like "FAR's state that transport category aircraft must
maintain a cabin altitude below 8,000 ft."

>> > christ on a bike <<

Indeed. Steve Martin; "Well Excuuuuuuse ME!"

Truce already.

[Big John]

Mish

Do you have enough bleed air with throttles at idle?

Thrust curve is not linear with throttle position so some rpm above
idle might be required in some birds???

Change in time down to 18K or so would not be much different. I used a
figure of 18K as a target alt to get on the safe side in a emergency
descent.

USAF set 34K (cockpit altitude) as the point to go to pressure
breathing. Easy to suck in and fill lungs and hard to breath out (open
exhaust valve). This assisted the lungs to get enough oxy. Took a
while to accustom to blowing out with each breath against valve but
soon became routine.

Big John
Pilot ROCAF


On Mon, 05 Jan 2004 18:38:52 GMT, "Gary Mishler"
> wrote:

>
>"Scott M. Kozel" > wrote in message
...
>> How could an SST like the Concorde get from cruising altitude down to
>> 10,000 feet in 3-5 minutes?
>
>Easy, it's called an Emergency Descent. Power to idle, spoilers/speedbrakes
>deployed, maybe gear extended (depends on aircraft), then dive at redline
>speed. The airplane I fly (Lear 60) it takes an initial deck angle of ~ 20
>degrees nose down to obtain redline, then ~ 10-12 degrees to hold it there.
>
>We practice it every time we have a simulator check. Never takes more than
>3 mins to get from FL450 to 10,000 ft.
>
>Mish
>

[Big John]

All seem to forget that a hijacked plane will probably have a pair of
F-16"s in trail and can be given authority to shoot the bird down with
all on board going kaput.

Which do you want, one or two or the whole plane and God knows how
many on the ground?

A shoot out at the OK corral seems to me to be preferable.

Big John


On 5 Jan 2004 16:45:09 -0800,
(running with scissors) wrote:

>"C J Campbell" > wrote in message >...
>> "Ron Natalie" > wrote in message
>> m...
>> |
>> | "C J Campbell" > wrote in message
>> ...
>> |
>> | > We do not really know any such thing. If the passenger is bigger than
>> the
>> | > window he simply cannot be pulled through it any more than he can sucked
>> up
>> | > through a vacuum cleaner hose.
>> | >
>> | Passengers are pretty flexible. Some might plug up the hole, others
>> will
>> | go through holes that looked like they ought not to fit through.
>> |
>>
>> The windows are surprisingly large, too. I have no doubt that a small person
>> could get through one, especially if his seatbelt is not properly fastened.
>> However, you are not going to lose a whole planeload of passengers this way.
>> Given a choice, I would shoot a hijacker with the off chance of killing an
>> innocent bystander rather than allow the hijacker to drive the plane into a
>> crowded building.
>
>
>ok.. interesting scenario. but what would be the option if the
>hijacker was a midget ??

[running with scissors]

"khobar" > wrote in message news:<QLDKb.17987$7D3.1116@fed1read02>...
> running with scissors > wrote in
> message om...
> > "khobar" > wrote in message
> news:<W_qKb.17919$7D3.14891@fed1read02>...
> > > running with scissors > wrote
> in
> > > message om...
> > > > "John Gilmer" > wrote in message
> >...
> > > > > "Bob Gardner" > wrote in message
> > > > > news:QODIb.85072$VB2.187788@attbi_s51...
> > > > > > No way. You start off at sea level, of course, and they pump the
> chamber
> > > > > > pressure down to 25000 feet with masks on...then they do some
> experiments
> > > > > > with a few of the pilots taking their masks off, just to show how
> severely
> > > > > > their abilities are affected. Then comes the explosive
> decompression,
> which
> > > > > > takes the chamber from 25K back down to sea level in a second or
> two.
> > > > >
> > > > > SIlly question but ...
> > > > >
> > > > > Why would "they" pressurize the aircraft to sea level? Why not
> some
> > > > > compromise "pressure" like that equivalent to, say, 6,000 or 8,000
> feet?
> > > > >
> > > > >
> > > > > EMWTK
> > > >
> > > > "they" dont. cabin pressurization is normally at 8000ft though crew
> > > > may elect to use different cabin pressures under certain circumstances
> > > > (eg medevac operations where pressurization is a factor)
> > >
> > > Sec. 25.1 Applicability.
> > >
> > > (a) This part prescribes airworthiness standards for the issue of type
> > > certificates, and changes to those certificates, for transport category
> > > airplanes.
> > >
> http://www.astech-engineering.com/systems/avionics/aircraft/faapart25d.html#
> > > Pressurization
> > >
> > > Sec. 25.841 Pressurized cabins.
> > >
> > > "(a) Pressurized cabins and compartments to be occupied must be equipped
> to
> > > provide a cabin pressure altitude of not more than 8,000 feet at the
> maximum
> > > operating altitude of the airplane under normal operating conditions."
> > >
> > > Transport category:
> > >
> > > * All jets with 10 or more seats or greater than 12,500lb Maximum
> > > Takeoff Weight.
> > > * All propeller driven airplanes with greater than 19 seats or
> greater
> > > than 19,000lb Maximum Takeoff Weight.
> > >
> > >
> > > Obviously the rule would not normlly apply to Medivac operations.
> > >
> > > HTH,
> > >
> > > Paul Nixon
> >
> > medevac ops are not exempt. though under certain medical conditions
> > the cabin my not be pressurized or pressurized to a lower altitude.
> > nitrogen narcosis is one condition that springs to mind.
>
> I was thinking about medivac helicopters. Dunno why since medivac goes
> beyond helicopter operations. Oh well...
>
> Paul Nixon


pressurized heli ?

[khobar]

running with scissors > wrote in
message om...
> "khobar" > wrote in message
news:<QLDKb.17987$7D3.1116@fed1read02>...
> > I was thinking about medivac helicopters. Dunno why since medivac goes
> > beyond helicopter operations. Oh well...
> >
> > Paul Nixon
>
>
> pressurized heli ?

Just a minor short in the headset. I had helicopters on my mind when posting
the applicability part.

Paul Nixon

[Rich Ahrens]

Morgans wrote:

> "running with scissors" > wrote >
>
>>christ on a bike. i knew this would happen.
>>
>
> Christ didn't ride no bike. I've had enough of you. You are abusive, and
> now profane. I'll not hang around for strike three.
>
> Plonk

Oh dear. That had to hurt something awful...

[Morgans]

"running with scissors" > wrote >
>
> christ on a bike. i knew this would happen.
>
Christ didn't ride no bike. I've had enough of you. You are abusive, and
now profane. I'll not hang around for strike three.

Plonk
--
Jim in NC

[running with scissors]

"Gary Mishler" > wrote in message news:<6VEKb.750520$HS4.5879879@attbi_s01>...
> "running with scissors" > wrote in
> message m...
>
> > > > > > "they" dont. cabin pressurization is normally at 8000ft ...
>
> I noted:
> > > > > Actually, it depends on the aircraft...
>
> < Explanation of pressurization certification, that some may find
> informative, snipped. >
>
> An anonomyus person calling himself "running with scissors" replied with:
>
> > christ on a bike. i knew this would happen.
> >
> > i stated "normally at 8,000ft", of course there are variations in
> > type, SOP and so on. i really didnt want to spend hours typing out a
> > list types and representative pressurization variations or a list of
> > SOP's for various operators of various types as either way it is going
> > to depend on what is set on the selector. say 8,000ft and someone will
> > say "we fly at 7,500".
> >
> > the answer is in the FAR's.
>
>
> Whoa big fella, cool your jets there.
>
> > the answer is in the FAR's.
>
> Indeed it is. If someone offering further information for the benefit of
> others in the NG was going to get your gander up so high, you could have
> said something like "FAR's state that transport category aircraft must
> maintain a cabin altitude below 8,000 ft."
>
> >> > christ on a bike <<
>
> Indeed. Steve Martin; "Well Excuuuuuuse ME!"
>
> Truce already.

big fella ? oh you flatter me !

uh huh, ron natalie did state that in an earlier post. no probs on the
truce, pulse and blood pressure still in the green arc.

[running with scissors]

"Morgans" > wrote in message >...
> "running with scissors" > wrote >
> >
> > christ on a bike. i knew this would happen.
> >
> Christ didn't ride no bike. I've had enough of you. You are abusive, and
> now profane. I'll not hang around for strike three.
>
> Plonk


moped then?

care to show where i have been abusive in this thread ?? and as for
profanity in the wording "christ on a bike" ? oh grow up.

[G.R. Patterson III]

Morgans wrote:
>
> Christ didn't ride no bike.

I thought that's how he wound up on a crutch?

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

[Morgans]

"Rich Ahrens" > wrote in message
...
> Morgans wrote:
>
> > "running with scissors" > wrote
>
> >
> >>christ on a bike. i knew this would happen.
> >>
> >
> > Christ didn't ride no bike. I've had enough of you. You are abusive,
and
> > now profane. I'll not hang around for strike three.
> >
> > Plonk
>
> Oh dear. That had to hurt something awful...

<Chuckle>

That hurt me, more than it hurt him. "Not"

It felt good from my end, and I have had a crapper of a day.
--
Jim in NC

[running with scissors]

"Morgans" > wrote in message >...
> "Rich Ahrens" > wrote in message
> ...
> > Morgans wrote:
> >
> > > "running with scissors" > wrote
>
> > >
> > >>christ on a bike. i knew this would happen.
> > >>
> > >
> > > Christ didn't ride no bike. I've had enough of you. You are abusive,
> and
> > > now profane. I'll not hang around for strike three.
> > >
> > > Plonk
> >
> > Oh dear. That had to hurt something awful...
>
> <Chuckle>
>
> That hurt me, more than it hurt him. "Not"
>
> It felt good from my end, and I have had a crapper of a day.


yeah i am all cut up about it.

[Ralph Nesbitt]

"Morgans" > wrote in message
...
>
> "Rich Ahrens" > wrote in message
> ...
> > Morgans wrote:
> >
> > > "running with scissors" >
wrote
> >
> > >
> > >>christ on a bike. i knew this would happen.
> > >>
> > >
> > > Christ didn't ride no bike. I've had enough of you. You are
abusive,
> and
> > > now profane. I'll not hang around for strike three.
> > >
> > > Plonk
> >
> > Oh dear. That had to hurt something awful...
>
> <Chuckle>
>
> That hurt me, more than it hurt him. "Not"
>
> It felt good from my end, and I have had a crapper of a day.
> --
> Jim in NC
>
If you are so thin skinned as to be so offended by such a mild statement of
"Self Frustration", IMHO it is no wonder you have had such a "crapper of a
day".
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Tom Sixkiller]

"G.R. Patterson III" > wrote in message
...
>
>
> Morgans wrote:
> >
> > Christ didn't ride no bike.
>
> I thought that's how he wound up on a crutch?
>
Red Sea Pedestrian, actually.

[running with scissors]

"khobar" > wrote in message news:<aqIKb.18693$7D3.14245@fed1read02>...
> running with scissors > wrote in
> message om...
> > "khobar" > wrote in message
> news:<QLDKb.17987$7D3.1116@fed1read02>...
> > > I was thinking about medivac helicopters. Dunno why since medivac goes
> > > beyond helicopter operations. Oh well...
> > >
> > > Paul Nixon
> >
> >
> > pressurized heli ?
>
> Just a minor short in the headset. I had helicopters on my mind when posting
> the applicability part.
>
> Paul Nixon

lol

[running with scissors]

"Morgans" > wrote in message >...
> "Rich Ahrens" > wrote in message
> ...
> > Morgans wrote:
> >
> > > "running with scissors" > wrote
>
> > >
> > >>christ on a bike. i knew this would happen.
> > >>
> > >
> > > Christ didn't ride no bike. I've had enough of you. You are abusive,
> and
> > > now profane. I'll not hang around for strike three.
> > >
> > > Plonk
> >
> > Oh dear. That had to hurt something awful...
>
> <Chuckle>
>
> That hurt me, more than it hurt him. "Not"
>
> It felt good from my end, and I have had a crapper of a day.


you mean every day isnt like that ? driving a checker cab and all ?

[running with scissors]

"Gary Mishler" > wrote in message news:<6VEKb.750520$HS4.5879879@attbi_s01>...
> "running with scissors" > wrote in
> message m...
>
> > > > > > "they" dont. cabin pressurization is normally at 8000ft ...
>
> I noted:
> > > > > Actually, it depends on the aircraft...
>
> < Explanation of pressurization certification, that some may find
> informative, snipped. >
>
> An anonomyus person calling himself "running with scissors" replied with:
>
> > christ on a bike. i knew this would happen.
> >
> > i stated "normally at 8,000ft", of course there are variations in
> > type, SOP and so on. i really didnt want to spend hours typing out a
> > list types and representative pressurization variations or a list of
> > SOP's for various operators of various types as either way it is going
> > to depend on what is set on the selector. say 8,000ft and someone will
> > say "we fly at 7,500".
> >
> > the answer is in the FAR's.
>
>
> Whoa big fella, cool your jets there.
>
> > the answer is in the FAR's.
>
> Indeed it is. If someone offering further information for the benefit of
> others in the NG was going to get your gander up so high, you could have
> said something like "FAR's state that transport category aircraft must
> maintain a cabin altitude below 8,000 ft."
>
> >> > christ on a bike <<
>
> Indeed. Steve Martin; "Well Excuuuuuuse ME!"
>
> Truce already.

unless of course the aircraf tin operation is not on the US reg, then
the answer wont be in the FAR's *G*

[running with scissors]

"Tom Sixkiller" > wrote in message >...
> "G.R. Patterson III" > wrote in message
> ...
> >
> >
> > Morgans wrote:
> > >
> > > Christ didn't ride no bike.
> >
> > I thought that's how he wound up on a crutch?
> >
> Red Sea Pedestrian, actually.


groan !

[Morgans]

"Ralph Nesbitt" > wrote

> If you are so thin skinned as to be so offended by such a mild statement
of
> "Self Frustration", IMHO it is no wonder you have had such a "crapper of a
> day".
> Ralph Nesbitt

You know nothing about me, or the thickness of my skin, or why my day
sucked. Get back in your cage, little man.
--
Jim in NC

[Ralph Nesbitt]

"Morgans" > wrote in message
...
>
> "Ralph Nesbitt" > wrote
>
> > If you are so thin skinned as to be so offended by such a mild statement
> of
> > "Self Frustration", IMHO it is no wonder you have had such a "crapper of
a
> > day".
> > Ralph Nesbitt
>
> You know nothing about me, or the thickness of my skin, or why my day
> sucked. Get back in your cage, little man.
> --
> Jim in NC
>
You are correct. I know nothing about you. Considering your reactions in
this thread, I do not care to know anything about you or why you had a bad
day.

I have heard it said " Treat/Address others as you would like to be
treated/addressed. If you address/treat those you interact with on a daily
basis the same as you have me,a total stranger, there is no wonder you had a
bad day.
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[running with scissors]

"Morgans" > wrote in message >...
> "Ralph Nesbitt" > wrote
>
> > If you are so thin skinned as to be so offended by such a mild statement
> of
> > "Self Frustration", IMHO it is no wonder you have had such a "crapper of a
> > day".
> > Ralph Nesbitt
>
> You know nothing about me, or the thickness of my skin, or why my day
> sucked. Get back in your cage, little man.


obviously had another ****ty day behind the wheel of a yellow taxi.

[Tom Sixkiller]

"running with scissors" > wrote in
message m...
> "Tom Sixkiller" > wrote in message
>...
> > "G.R. Patterson III" > wrote in message
> > ...
> > >
> > >
> > > Morgans wrote:
> > > >
> > > > Christ didn't ride no bike.
> > >
> > > I thought that's how he wound up on a crutch?
> > >
> > Red Sea Pedestrian, actually.
>
>
> groan !

Thow him to the floor!

[Geoffrey Barnes]

"Tom Sixkiller" > wrote in message...
> Thow him to the floor!

I have a fwiend in Wome named Bigus Dickus!

[running with scissors]

"Tom Sixkiller" > wrote in message >...
> "running with scissors" > wrote in
> message m...
> > "Tom Sixkiller" > wrote in message
> >...
> > > "G.R. Patterson III" > wrote in message
> > > ...
> > > >
> > > >
> > > > Morgans wrote:
> > > > >
> > > > > Christ didn't ride no bike.
> > > >
> > > > I thought that's how he wound up on a crutch?
> > > >
> > > Red Sea Pedestrian, actually.
> >
> >
> > groan !
>
> Thow him to the floor!


stwike him centuwion vewy woughly

[Ralph Nesbitt]

"Morgans" > wrote in message
...
>
> "Ralph Nesbitt" > wrote > >
> > You are correct. I know nothing about you. Considering your reactions in
> > this thread, I do not care to know anything about you or why you had a
bad
> > day.
> >
> > I have heard it said " Treat/Address others as you would like to be
> > treated/addressed. If you address/treat those you interact with on a
daily
> > basis the same as you have me,a total stranger, there is no wonder you
had
> a
> > bad day.
> > Ralph Nesbitt
> > Professional FD/CFR/ARFF Type
> >
> Seems you didn't keep your rule in mind when you addressed me.
>
> How 'bout this. Let's start new.
> --
> Jim in NC
>
Up to you. I have heard it said: "give as good as I get, plus a wee tad bit
better, without being offensive, & you will always come out alright, plus be
invited back for more".
Ralph Nesbitt
Professional FD/CFR/ARFF Type

[Gary Mishler]

"running with scissors" > wrote in
message om...

>no probs on the
> truce, pulse and blood pressure still in the green arc.

Sounds good!

[Morgans]

"Ralph Nesbitt" > wrote > >
> You are correct. I know nothing about you. Considering your reactions in
> this thread, I do not care to know anything about you or why you had a bad
> day.
>
> I have heard it said " Treat/Address others as you would like to be
> treated/addressed. If you address/treat those you interact with on a daily
> basis the same as you have me,a total stranger, there is no wonder you had
a
> bad day.
> Ralph Nesbitt
> Professional FD/CFR/ARFF Type
>
Seems you didn't keep your rule in mind when you addressed me.

How 'bout this. Let's start new.
--
Jim in NC

[Gary Mishler]

"Big John" > wrote in message
...

> Do you have enough bleed air with throttles at idle?
>
> Thrust curve is not linear with throttle position so some rpm above
> idle might be required in some birds???

The Lear 60 has big Pratts on it so it does have enough bleed air to run
everything at idle. The 50 and 30 series Lears I flew didn't usually have
enough bleed air at idle to run both pressurization and anti-ice. Like you
said above, on those planes you had to have some power greater than idle to
hold the cabin with anti-ice on.

Now on the old 20 series lears I hear you had to have the rpm up just to
hold cabin altitude.

Hope that answers your question,
Mish

[running with scissors]

"Gary Mishler" > wrote in message news:<w7pLb.2220$8H.14005@attbi_s03>...
> "running with scissors" > wrote in
> message om...
>
> >no probs on the
> > truce, pulse and blood pressure still in the green arc.
>
> Sounds good!

that it is. have a good one!

[Jack Davis]

On Mon, 05 Jan 2004 18:07:59 -0700, Michael Williamson
> wrote:

>That is to say that if you take off from sea level and climb
>to 10,000', the cabin altitude will steadily climb, at a rate
>set by the cabin pressure controller, toward 8,000'. If you
>were to level off at 5,000' and stay there long enough for
>the cabin pressure to catch up, it will maintain 5,000'
>until the aircraft begins to climb again,

This is not true on Boeing aircraft. In flight, the pressure
controller maintains a "proportional" pressure differential between
aircraft and cabin altitude.

If the aircraft levels off at an intermediate altitude, the cabin will
not continue to climb but will level off also - it will not "catch up"
to the aircraft (actual) altitude.

(This only refers to Boeing aircraft and the DC-9. YMMV.)

-J

Jack Davis
B-737


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[Jack Davis]

On Fri, 2 Jan 2004 23:09:12 -0500, "John Gilmer"
> wrote:

>Just how does the psia in the cabin track the psia "ambient."

This information is fed to the pressure controller by the Air Data
Computer (ADC) on older aircraft and by the Air Data Inertial
Reference Unit (ADIRU) on newer aircraft.

-J

Jack Davis
B-737


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[Ron Natalie]

"Jack Davis" > wrote in message ...


> (This only refers to Boeing aircraft and the DC-9. YMMV.)
>
The DC-9 is a Boeing aircraft these days (danged mergers and
acquisitions).

[Jack Davis]

On Tue, 13 Jan 2004 14:10:03 -0500, "Ron Natalie" >
wrote:

>The DC-9 is a Boeing aircraft these days (danged mergers and
>acquisitions).

I figured someone would jump on that... I will *never* be able to
call the -9 a Boeing!

-J

Jack Davis
B-737


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