On May 19, 8:43 pm, "Ken S. Tucker" wrote:

That isn't possible.

Sure it is.
As long as you're not accelerating, which is something
that can be sensed by audio RPM , the magnetic
compass can operate as an artificial horizon too,
because it's like a plumb-bob.
It's of course, independant of operating systems.

You haven't flown, really, have you? If you had, you'd
know that the compass, being suspended from a pivot, is kept upright
by gravity, just like the ball in the turn coordinator stays in the
bottom of its tube by gravity. However, in a coordinated turn, the
TC's ball stays centered and the compass's card stays level with the
airplane's wings, not with the horizon. If it did we wouldn't need to
spend $900 on an attitude indicator; we could use the ball and
compass.
The compass reads all haywire during turns, too, not just
during acceleration. You can't use it to roll out on a heading. Timed
turns are for that.
Both you and Mx would be awful surprised the first time you
flew under the hood or in IMC. Vertigo, or what we call "crookedhead"
around here, would get you big time in no time. It surprises all new
guys, especially guys who "have it all figured out" and are trying to
teach the teachers. They come home with their tails between their
legs, same as the know-it-all trike pilot who has just had his first
taildragger experience.

Dan