Catastrophic Decompression; Small Place Solo

"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.

"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.

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

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 ??

"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/sy...apart25d.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 ?

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

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...

"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

"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.

"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.