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Old 16th Nov 2018, 07:16
  #1300 (permalink)  
Grunff
 
Join Date: Apr 2009
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Originally Posted by Hi_Tech
For all those questions about WHY this MCAS on B737 MAX fleet, the following link has a very nice easy to follow explanation with clear graphics written by a test pilot Bjorn Fehrm.
When you apply a lot of lipstick to an old lady like B737, something else goes wrong. Boeing had to do this change as the large engines made the aircraft stability to go wrong. Thanks Bjorn. I think it will clear up several questions about MCAS, STS, etc. in this forum.

link removed
Great explanation. Basically, bigger and more powerful donks hung further away/forward from centre of gravity. Larger nacelles potential "flipping-the-aircraft-around" effect in turns/high-AoA was then masked by undisclosed software patch which might have contributed to the crash.
One wonders why Boeing insists on keeping the basic wing unchanged. It would save them lots of headache if it could be moved up a bit (=enable GTF, make it less "flippable" etc.) (I suppose there are certification bills that prevented this, so more lipstick was applied )
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