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Don wrote:
<Need some input on others experience with the Pitch sensitivity on the S-Tec
50 A/P.  And what was their solution to over sensitivity, if any ???>

1)  Go to   http://www.s-tec.com/  and look at the tech letters.  This will address many S-Tec questions.

2) S-Tec has indicated that subjecting the static pressure sensor to vibration may cause problems with altitude hold.  I now have mine mounted on rubber bushings.

3) The sensor may be bad - there is a test for a certain voltage off one of the sensor leads (like the Clinton administration, I don't remember).  Check the Tech letters or call S-Tech.  BTW, my sensor was bad which resulted in porpoising.

4)  If your S-Tec installation/equipment is old (Circa the early nineties), the computer may be too sensitive and the servo rate too fast.  Another symptom was a saw-tooth or stepping action to achieve the bank angle for a turn.  S-Tec fixed this for me.

5) Trim for level flight at your final settled cruise speed before engaging Altitude hold.  If the trim light comes on, disengage Alt Hold and retrim.

6) Make sure there is no "lash" or looseness in the elevator system, including the servo-elevator interface. If you use a "cable" interface, are the cables taut?

She runs steady as a rock now.


Scott Krueger
N92EX
   

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