On Wed, 13 Sep 2006 05:01:18 GMT, Matt Whiting
wrote in :

Larry Dighera wrote:

On Wed, 13 Sep 2006 01:27:58 GMT, Matt Whiting
wrote in :


The only thing that makes a
compass not trustworthey is an unknown magnetic field that may have been
brought into the airplane.


Of course, there's also electromagnetism...

I didn't specify the source of the magnetic field. :-)


No you didn't.

I would think it possible for portable wiring plugged into a cigarette
lighter to be a possible source of magnetism capable of affecting a
compass. I suppose, if both wires are parallel and adjacent, their
fields would cancel, but I wouldn't stake my life on it.