"David Cartwright" wrote in message
...
"Greg" wrote in message
ups.com...
In primary and supporting method of attitude instrument flying, which
do you consider the primary instrument for bank in the partial panel
situation (loss of both attitude indicator and heading indicator)?
Turn coordinator or magnetic compass?

The turn co-ordinator is your primary measure of bank, for a couple of
reasons. First, the compass doesn't measure bank angle - it just shows
what direction you're pointing in - whereas the TC does show the degree to
which you're banked.

The turn coordinator shows direction and rate of turn but no bank angle.
You can do a skidding standard rate turn with the wings level by applying
rudder in one direction and opposite aileron to keep the wings level. In a
coordinated turn it does somewhat show bank angle but the faster your
airspeed the more bank angle is required to achieve standard rate.

I agree with using the TC over the compass if it is avalable. Following is a
quote out of the Wikipedia, for what it's worth:
"Aircraft compass turns are used in an aircraft when other directional
instruments, such as the directional gyro or turn coordinator, have failed."
http://en.wikipedia.org/wiki/Aircraft_compass_turns


Allen