On Sat, 02 Sep 2006 21:30:18 -0000, Jim Logajan
wrote:

"RST Engineering" wrote:
There is one, and ONLY one instrument in the aircraft that does not
require a power source or have a common catastrophic failure mode.

You mean the wings or the pilot?

Ducks and runs

What about a compromise?
Calibrate the compass as normal but have the lubber line variable so
you can preset the magnetic variation for the area you fly. That way
you can use true headings based on the compass. Maybe a problem if
your partial panel and are using the compass.

The only snag I see is in areas of very large variation. If the
variation was too large I guess you start getting parallax errors too.

Do the modern solid state compasses have provision to change the
variation? That would make it easy or am I missing something?