"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
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.



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.