PPRuNe Forums - View Single Post - Boeing 737 Max Software Fixes Due to Lion Air Crash Delayed
Old 23rd Mar 2019, 08:22
  #341 (permalink)  
DaveReidUK
 
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Originally Posted by Dan Winterland
There's something fundamentally wrong here. The AoA sensors on the Max are failing. They are normally very reliable - I've never seen one fail in about 10,000 hours of flying aircraft with the same sensors. What you do notice while doing the walk around check is that they are fully deflected up if reverse thrust was used on the previous landing. The Max has engines moved far forward of the original position. Perhaps the sensors are being damaged by use of reverse thrust.
Interesting post.

I don't buy either the "bad bit" argument, nor the theory that the sensor was fitted wrongly oriented (presumably after the locating pegs had been sawn off!), but physical misalignment of the vane relative to the armature would be another explanation for the consistent AoA offset error.

If the latter is the case, I wouldn't rule out the possibility of the damage having been sustained before it was fitted to the accident aircraft.
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