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Old 22nd Nov 2018, 23:52
  #1541 (permalink)  
Join Date: Mar 2014
Location: WA STATE
Age: 74
Posts: 1
Originally Posted by FCeng84 View Post
AGBagb - Activation of the both stab cutout switches should disable all electric control of the stabilizer. One can, however, imagine a failure that involves one or more electrical shorts that yields runaway stabilizer that is not arrested via the cutout switches. For that reason, the checklist has #4 suggesting that as a last effort, physically stopping the trim wheel on the flight deck will freeze the stabilizer. MCAS should be disabled via activation of the cutout switches. Short of a failure with the stabilizer electric motors that is separate from MCAS, activating both cutout switches will stop MCAS from moving the stabilizer.
1) Can the motors stand a high rate multiple operation x minutes duty cycle without damage- lockup
2) If locked due to 1 above, can trim wheel still move stab?
3) Is there enough mechanical advantage via trim wheel to move stab from extreme position- airloads ?

Last edited by CONSO; 23rd Nov 2018 at 01:38.
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