pitot tube down

[Emilio]

A portion of thread from different news grope:

>loss of a 757 a few years ago in which clogged pitot tubes
>caused bad overspeed warnings; the Turkish crew pulled
>back the power and stalled and crashed. It was later determined
>that the A/C had sat for a month and insects had gotten into
>uncovered pitot tubes.

With aircraft equipped with GPS that shows your true speed, can you fly by
it when pitot tube is down?

Emilio.

[Keith Willshaw]

"Emilio" > wrote in message
...
> A portion of thread from different news grope:
>
> >loss of a 757 a few years ago in which clogged pitot tubes
> >caused bad overspeed warnings; the Turkish crew pulled
> >back the power and stalled and crashed. It was later determined
> >that the A/C had sat for a month and insects had gotten into
> >uncovered pitot tubes.
>
> With aircraft equipped with GPS that shows your true speed, can you fly by
> it when pitot tube is down?
>
> Emilio.
>
>

There's a risk if you do. The GPS will give you the speed over ground
but the pitot gives you airspeed. If you were flying an aircraft
with a stalling speed of 120 mph downwind and the GPS
showed 150 you could stall if the tail wind was more than
30 mph

Keith

[Tarver Engineering]

"Emilio" > wrote in message
...
> A portion of thread from different news grope:
>
> >loss of a 757 a few years ago in which clogged pitot tubes
> >caused bad overspeed warnings; the Turkish crew pulled
> >back the power and stalled and crashed. It was later determined
> >that the A/C had sat for a month and insects had gotten into
> >uncovered pitot tubes.
>
> With aircraft equipped with GPS that shows your true speed, can you fly by
> it when pitot tube is down?

The Captain's static port on the 757 had duct tape over it. The FO side was
working just fine, so there was not much excuse for crashing.

[Mortimer Schnerd, RN]

Tarver Engineering wrote:
>> With aircraft equipped with GPS that shows your true speed, can you fly by
>> it when pitot tube is down?
>
> The Captain's static port on the 757 had duct tape over it. The FO side was
> working just fine, so there was not much excuse for crashing.


As I recall, the trim settings are the same for cruise and with full flaps. I
had a bug invade my pitot tube once in a Piper Lance and just muscled the
airplane from cruise until I had all the flaps set on approach. I never touched
the trim. I have no idea how close I was to target airspeed but the resulting
landing was quite normal. The airspeed indicator was dead the whole time.



--
Mortimer Schnerd, RN


http://www.mortimerschnerd.com

[Tarver Engineering]

"Mortimer Schnerd, RN" > wrote in message
. com...
> Tarver Engineering wrote:
> >> With aircraft equipped with GPS that shows your true speed, can you fly
by
> >> it when pitot tube is down?
> >
> > The Captain's static port on the 757 had duct tape over it. The FO side
was
> > working just fine, so there was not much excuse for crashing.
>
>
> As I recall, the trim settings are the same for cruise and with full
flaps. I
> had a bug invade my pitot tube once in a Piper Lance and just muscled the
> airplane from cruise until I had all the flaps set on approach. I never
touched
> the trim. I have no idea how close I was to target airspeed but the
resulting
> landing was quite normal. The airspeed indicator was dead the whole time.

Panic seems to be the reason people don't think their way out of these kind
of single point failures. I have to winder if the pilot didn't expect to
have to do more than raise the wheels and adjust the flaps.

[Darrell]

I wouldn't take off with an inoperative pitot tube and depend on my GPS
ground speed read out but....
if you're already inflight when you lose your IAS indicator it would be
really smart to pull out your GPS and use the ground speed read out as an
gross indication of your indicated airspeed. Maintain a large margin over
your desired IAS until you enter an area like landing where you want to be
somewhat near the correct speed. Check the headwind and add that to your
desired IAS on final. I'd maybe add 10 knots to that for safety.

--

B-58 Hustler History: http://members.cox.net/dschmidt1/
-

"Emilio" > wrote in message
...

> A portion of thread from different news grope:
> With aircraft equipped with GPS that shows your true speed, can you fly by
> it when pitot tube is down?
>
> Emilio.
>
>

[W. D. Allen Sr.]

How did they even get the 757 off the ground?

WDA

end

"Emilio" > wrote in message
...
> A portion of thread from different news grope:
>
> >loss of a 757 a few years ago in which clogged pitot tubes
> >caused bad overspeed warnings; the Turkish crew pulled
> >back the power and stalled and crashed. It was later determined
> >that the A/C had sat for a month and insects had gotten into
> >uncovered pitot tubes.
>
> With aircraft equipped with GPS that shows your true speed, can you fly by
> it when pitot tube is down?
>
> Emilio.
>
>

[C Knowles]

Not that familiar with the 757 but GPS displays GS. Add or subtract winds to
get TAS, then correct for density (divide by SMOE) to get IAS?CAS. Heard it
suggested you could also depressurize and use the cabin altimeter for
altitude. Or, convert cabin altitude into aircraft altitude if the chart is
available.
Curt


"Emilio" > wrote in message
...
> A portion of thread from different news grope:
>
> >loss of a 757 a few years ago in which clogged pitot tubes
> >caused bad overspeed warnings; the Turkish crew pulled
> >back the power and stalled and crashed. It was later determined
> >that the A/C had sat for a month and insects had gotten into
> >uncovered pitot tubes.
>
> With aircraft equipped with GPS that shows your true speed, can you fly by
> it when pitot tube is down?
>
> Emilio.
>
>

[Leadfoot]

"C Knowles" > wrote in message
. com...
> Not that familiar with the 757 but GPS displays GS. Add or subtract winds
to
> get TAS, then correct for density (divide by SMOE) to get IAS?CAS. Heard
it
> suggested you could also depressurize and use the cabin altimeter for
> altitude. Or, convert cabin altitude into aircraft altitude if the chart
is
> available.
> Curt

Multiple redundant systems on Commercial jets. Figure out which one is bad
and turn it off. The standby #3 system is analog and totally separate if
it's like a 747-400. The captain should have given control to the copilot
in the turkish aircraft incident.


>
>
> "Emilio" > wrote in message
> ...
> > A portion of thread from different news grope:
> >
> > >loss of a 757 a few years ago in which clogged pitot tubes
> > >caused bad overspeed warnings; the Turkish crew pulled
> > >back the power and stalled and crashed. It was later determined
> > >that the A/C had sat for a month and insects had gotten into
> > >uncovered pitot tubes.
> >
> > With aircraft equipped with GPS that shows your true speed, can you fly
by
> > it when pitot tube is down?
> >
> > Emilio.
> >
> >
>
>

[Rick]

Tarver Engineering wrote:

> Panic seems to be the reason people don't think their way out of these kind
> of single point failures. I have to winder if the pilot didn't expect to
> have to do more than raise the wheels and adjust the flaps.
One of your series connections is open circuit, Tarver,

As a congenital idiot who couldn't learn to fly an aircraft in a
thousand years your statment above pretty much defines the level of your
knowledge of aircraft operations ... zilch.

Rick

[Tarver Engineering]

"Rick" > wrote in message
hlink.net...
> Tarver Engineering wrote:
>
> > Panic seems to be the reason people don't think their way out of these
kind
> > of single point failures. I have to winder if the pilot didn't expect
to
> > have to do more than raise the wheels and adjust the flaps.

> One of your series connections is open circuit, Tarver,
>
> As a congenital idiot who couldn't learn to fly an aircraft in a
> thousand years your statment above pretty much defines the level of your
> knowledge of aircraft operations ... zilch.

Since the FO's air data was correct, one can only believe you post from
ignorance, Rick. Robots fly 757 airplanes most of the time, but sometimes
the pilot has to operate.

I beleive UAVs are the way of the furture in the Military sense of the word
aviation.

[[email protected]]

"W. D. Allen Sr." > wrote:

>How did they even get the 757 off the ground?
>
>WDA

Well, it WAS a pretty confusing readout on the CVR tape for sure,
lots of shouts of 'what's it doing that for' and like
stuff,...but most of it seemed to happen after they were almost
off the ground (ISTR). I had the CVR transcript at one time. I
believe that they got up to several thousand feet at one point.
>

--

-Gord.

[C Knowles]

"Leadfoot" > wrote in message
news:f4c1c.9887$Zp.3539@fed1read07...
>
> "C Knowles" > wrote in message
> . com...
> > Not that familiar with the 757 but GPS displays GS. Add or subtract
winds
> to
> > get TAS, then correct for density (divide by SMOE) to get IAS?CAS.
Heard
> it
> > suggested you could also depressurize and use the cabin altimeter for
> > altitude. Or, convert cabin altitude into aircraft altitude if the chart
> is
> > available.
> > Curt
>
> Multiple redundant systems on Commercial jets. Figure out which one is
bad
> and turn it off. The standby #3 system is analog and totally separate if
> it's like a 747-400. The captain should have given control to the copilot
> in the turkish aircraft incident.
>


Well, that's only if you follow the flight manual and common sense.
Just discussed this one in my quarterly refresher. The discussion turned to
"what if" you lost all airspeed and altitude indications. It was an exercise
in making us think. It would also be a handy method to double check the
primary instruments, or to have something to do on those long overwaters.
Curt

[Tarver Engineering]

"C Knowles" > wrote in message
. com...
>
> "Leadfoot" > wrote in message
> news:f4c1c.9887$Zp.3539@fed1read07...
> >
> > "C Knowles" > wrote in message
> > . com...
> > > Not that familiar with the 757 but GPS displays GS. Add or subtract
> winds
> > to
> > > get TAS, then correct for density (divide by SMOE) to get IAS?CAS.
> Heard
> > it
> > > suggested you could also depressurize and use the cabin altimeter for
> > > altitude. Or, convert cabin altitude into aircraft altitude if the
chart
> > is
> > > available.
> > > Curt
> >
> > Multiple redundant systems on Commercial jets. Figure out which one is
> bad
> > and turn it off. The standby #3 system is analog and totally separate
if
> > it's like a 747-400. The captain should have given control to the
copilot
> > in the turkish aircraft incident.
> >
>
>
> Well, that's only if you follow the flight manual and common sense.
> Just discussed this one in my quarterly refresher. The discussion turned
to
> "what if" you lost all airspeed and altitude indications. It was an
exercise
> in making us think. It would also be a handy method to double check the
> primary instruments, or to have something to do on those long overwaters.

There would be no loss of airspeed indications. The airplane would seem
perfectly normal until there was no change in the altimeter. Get the
confusion about pitot tubes out of your head, as there is no relevence to
the discussion at hand. In fact, ignorance about transport air data
instrumentation may have contributed to the confusion the operator
displayed.

[B2431]

>From: "Tarver Engineering"
>Date: 3/4/2004 11:28 AM Central Standard Time
>Message-id: >
>
>
>"C Knowles" > wrote in message
. com...
>>
>> "Leadfoot" > wrote in message
>> news:f4c1c.9887$Zp.3539@fed1read07...
>> >
>> > "C Knowles" > wrote in message
>> > . com...
>> > > Not that familiar with the 757 but GPS displays GS. Add or subtract
>> winds
>> > to
>> > > get TAS, then correct for density (divide by SMOE) to get IAS?CAS.
>> Heard
>> > it
>> > > suggested you could also depressurize and use the cabin altimeter for
>> > > altitude. Or, convert cabin altitude into aircraft altitude if the
>chart
>> > is
>> > > available.
>> > > Curt
>> >
>> > Multiple redundant systems on Commercial jets. Figure out which one is
>> bad
>> > and turn it off. The standby #3 system is analog and totally separate
>if
>> > it's like a 747-400. The captain should have given control to the
>copilot
>> > in the turkish aircraft incident.
>> >
>>
>>
>> Well, that's only if you follow the flight manual and common sense.
>> Just discussed this one in my quarterly refresher. The discussion turned
>to
>> "what if" you lost all airspeed and altitude indications. It was an
>exercise
>> in making us think. It would also be a handy method to double check the
>> primary instruments, or to have something to do on those long overwaters.
>
>There would be no loss of airspeed indications. The airplane would seem
>perfectly normal until there was no change in the altimeter. Get the
>confusion about pitot tubes out of your head, as there is no relevence to
>the discussion at hand. In fact, ignorance about transport air data
>instrumentation may have contributed to the confusion the operator
>displayed.
>
>
That depends on the amount of change in altitude. If the change is significant
your IAS will show a decrease in velocity since it will no longer be
compensating for altitude. That's the reason IAS requires both pitot and
static.

Dan, U.S. Air Force, retired

[Tarver Engineering]

"B2431" > wrote in message
...
> >From: "Tarver Engineering"
> >Date: 3/4/2004 11:28 AM Central Standard Time
> >Message-id: >
> >
> >
> >"C Knowles" > wrote in message
> . com...
> >>
> >> "Leadfoot" > wrote in message
> >> news:f4c1c.9887$Zp.3539@fed1read07...
> >> >
> >> > "C Knowles" > wrote in message
> >> > . com...
> >> > > Not that familiar with the 757 but GPS displays GS. Add or subtract
> >> winds
> >> > to
> >> > > get TAS, then correct for density (divide by SMOE) to get IAS?CAS.
> >> Heard
> >> > it
> >> > > suggested you could also depressurize and use the cabin altimeter
for
> >> > > altitude. Or, convert cabin altitude into aircraft altitude if the
> >chart
> >> > is
> >> > > available.
> >> > > Curt
> >> >
> >> > Multiple redundant systems on Commercial jets. Figure out which one
is
> >> bad
> >> > and turn it off. The standby #3 system is analog and totally
separate
> >if
> >> > it's like a 747-400. The captain should have given control to the
> >copilot
> >> > in the turkish aircraft incident.
> >> >
> >>
> >>
> >> Well, that's only if you follow the flight manual and common sense.
> >> Just discussed this one in my quarterly refresher. The discussion
turned
> >to
> >> "what if" you lost all airspeed and altitude indications. It was an
> >exercise
> >> in making us think. It would also be a handy method to double check the
> >> primary instruments, or to have something to do on those long
overwaters.
> >
> >There would be no loss of airspeed indications. The airplane would seem
> >perfectly normal until there was no change in the altimeter. Get the
> >confusion about pitot tubes out of your head, as there is no relevence to
> >the discussion at hand. In fact, ignorance about transport air data
> >instrumentation may have contributed to the confusion the operator
> >displayed.
> >
> >
> That depends on the amount of change in altitude. If the change is
significant
> your IAS will show a decrease in velocity since it will no longer be
> compensating for altitude. That's the reason IAS requires both pitot and
> static.

Sure.

[Leadfoot]

> > > Not that familiar with the 757 but GPS displays GS. Add or subtract
> winds
> > to
> > > get TAS, then correct for density (divide by SMOE) to get IAS?CAS.
> Heard
> > it
> > > suggested you could also depressurize and use the cabin altimeter for
> > > altitude. Or, convert cabin altitude into aircraft altitude if the
chart
> > is
> > > available.
> > > Curt
> >
> > Multiple redundant systems on Commercial jets. Figure out which one is
> bad
> > and turn it off. The standby #3 system is analog and totally separate
if
> > it's like a 747-400. The captain should have given control to the
copilot
> > in the turkish aircraft incident.
> >
>
>
> Well, that's only if you follow the flight manual and common sense.
> Just discussed this one in my quarterly refresher. The discussion turned
to
> "what if" you lost all airspeed and altitude indications. It was an
exercise
> in making us think. It would also be a handy method to double check the
> primary instruments, or to have something to do on those long overwaters.
> Curt
>
>