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Old 13th May 2009, 21:37
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glhcarl
 
Join Date: Jan 2006
Location: Georgia, USA
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What about this? No elevator position indicators?
The elevator is slaved off the horiziontal stalilizer and therefore its position is shown on the Surface Position Indicator. Stabilizer nose down elevator trailing edge up, stabilizer nose up elevator trailing edge down.

The incident Jack MacHahan was involved in was caused by the failure of the bearing in the elevator drive quadrant prior to takeoff, during the controls check. When the bearing failed the stabilizer nose was full down and the elevator trailing edge full up. The drive quadrant tilted and was blocked by the elevator drive hockey stick pushrod. So the elevator could no longer follow the stabilizer and remained in the full up position.

There were several AD's and S/B's written to prevent re-ocurrance. With the final fix being a elevator cable jam detector being install in the aft body and a warning light on the flight engineers panel.
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