Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Wed, 24 Apr 2002 11:54:58 -0400
Message-ID: <redirect-1190299@logan.com>
From: Sky2high@aol.com
Subject: Re: [LML] Re: 40 degree compass error
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A friend with an E-Racer had a hopeless panel-mount compass error.  The 
problem was finally traced to the wire bundle passing behind the compass.  He 
sometimes overdid shields (grounded at both ends), underdid shields (none) 
or, perhaps created ground loops (she ain't no taildragger).  He finally 
moved his 12th Century Technology compass to the far side of the panel and 
mainly solved his problem.  Note that the E-Racer's engine is in the rear 
with the alternator as far away from the panel as possible (the pilot is also 
forward facing).  

Personally, I use a Vertical Card Compass (a joker for the FAA) mounted on 
top of and at the center of the glare shield.  It is only off V to XIV 
degrees (12th Century math to match) whenever I choose to look at it.  I 
mainly rely on an electronic compass and GPS ground track.

Note: Luckily I live in the Chicago area (0 degrees correction) and 
appreciate True North representation - The rest is guess-work when I travel 
to other longitudes and ATC only expects you to be within 10 or so degrees.  
If you use GPS, just ask ATC for the ground track they would like you to make 
and then surprise them by actually flying that track.

Grayhawk