On May 19, 7:08*am, Mxsmanic wrote:
A Lieberman writes:
Yep, go ahead, try leveling off with an AI ERRONEOUSLY showing a 20
pitch up. *Go ahead and trust that instrument.

The AI is the most reliable instrument on most aircraft, after the magnetic
compass. *And of course you'll want two, just in case one fails, for IFR..

Would love to know what your sources are on that information MX. in
all the aircraft I have flown both the AI and DI were powered from the
same vacuum pump and the pump is the most common cause of failure of
gyroscopic instruments. How do I know that? not from any books I have
read, and I have many on aviation, but from first hand advice from
several flying instructors, and actually had a vacuum pump failure in
a Warrior on one of my PPL flight tests ( and you are not allowed to
ask why I had more than one test :) )
Terry
PPL Downunder