Old 24th Jan 2012, 17:07
  #1142 (permalink)  
Jet Jockey A4
Join Date: Jan 2008
Location: CYUL
Posts: 855
I don't think it's reading GPS Speed but rather GPS Altitude.

Speed is on the left side of the ADI and is replaced by a coloured tape indication.

On the right side we usually find altitude information and my guess is the 000 is sea level and the 010 is a thounsand feet with the 520 being mid way on that scale so it's a 520 foot GPS Altitude read out.

Edited... Just noticed is actually says GPS ALT at the bottom of the scale so my assumption is correct!
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