pitot tube down

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.

"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

"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.

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

"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.

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.

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.

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.

"C Knowles" wrote in message
news
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.

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