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Old 11th Mar 2019, 08:49
  #291 (permalink)  
silverstrata
 
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Originally Posted by arketip
There is quite a difference between a trim runaway and what seems to happen here.
How do you recognise a trim runaway?
There is this volumous clanking noise going on, as the huge great Titanic trim wheel (taken from the Ju-52) winds its way around. And the controls will need a great deal of pulling for normal flight (something like 50 to 60 kg of force), which is pretty much uncontrollable.

However, if you have the very noisy stick shaker going off (as the Indonesia did), and if the instruments lead you to think you might be stalling (as the Indonesia thought), you are not necessarily know that the stab-trim is trimming.

Trouble-shooting multiple faults is never easy. Which takes priority ? Obviously controlling the perceived stall - that is why the stick shaker is operating. Except it is not a stall, and the most important thing is the trim runnaway - which you might nit even know is happening.

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