Re: Remote compass location and a steel sliding ca
We do not use the magnetometer at all for attitude solution. We use airspeed (if there) and GPS speed as a backup. The only thing the magnetometer is used for in our system is the heading.
On top of not using the magnetometer, our system can recover from any disruption in a few seconds. The reason the other system is thrown off by this error is that it levels itself when you boot it based on the magnetometer, and then uses that level reference for a very long time, if not the whole flight. So if the magnetometer is off at boot, the system is wrong for minutes, if not more. Our system can be powered on in flight, even in non-level flight, and can find level within a few seconds.
We've heard of the systems that use magnetometers being thrown off by just starting the system near some big metal object, like, say, a steel hangar.