Sender: rob
Message-ID: <40193711.C24F4776@Philips.com>
Date: Thu, 29 Jan 2004 11:38:41 -0500
From: Rob Logan <Rob.Logan@Philips.com>
Reply-To: Rob@Logan.com
MIME-Version: 1.0
To: lml@lancair.net
Subject: EIFS cal.
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one of the cool things about CFS or any EIFS is how accurate they are,
but one of the biggest pains is getting the calibration perfect.
 
my favorite example of this is when I didn't have the peto/stadic system
quite right so when I did a ground runup the airspeed indicator would show
30kts..  and the EIFS would show me leaving the runup pad and one second
later I would "jump" back to my real location and then zoom off the
runup pad again for the next second...  this is all fun during the
testing phase, but there comes a time when one wants real numbers. 
 
one of the harder things to know what level flight really is..  (and it
changes with weight BTW) but if one downloads a long VFR flight that was
mostly spent on AP, and then plot pitch and roll, your eye can DSP about
where level flight is...  (I was .9^o in pitch and -.4^o in roll) now in
the hanger, use your jack stands and a testing program to read the raw
output of gyros and jack the plane to what you saw in "level flight"  Now 
go in and shim the gyros to 0 to give the EIFS perfect numbers. while you
have the plane "locked" in level flight, you should also calibrate your 
gas tanks again..
 
yea, steam gauge guys don't hafta do all this, but isn't it
fun to know down to .5gal how much gas you have in each tank :-)

-- 
Utopian Maturity: Eternity, Liberty, Equality now Fraternity & Altruism.