Simviation Forums

If you've ever wandered through the woods with a compass in-hand; you've figured out that it only reads accurately, when you're either standind still (or walking at a steady pace), and it is help perfectly level. Same deal for compasses in airplanes.

I won't get into the techy mush about how, bank/pitch/accelleration skew compasses. All you need to know for simming, is that anything other than level, constant-airspeed flight, can make a compass read erroneously. The only variables worth noting; are that banking has more of an effect on the north/south readings.. and acceleration (speeding up OR slowing down) has more of an effect on east/west readings.. and of course those two factors overlap

If I recall correctly, the degrees of error in the N/S turning is affected by latitude. Where I am it's about 30 degrees like you mention, but  I don't recall whether it gets more or less when the latitude changes north or south.

Nothing like a partial panel IFR approach with no ATC vectors.  ;)