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Old 11th Mar 2019, 16:56
  #394 (permalink)  
silverstrata
 
Join Date: Mar 2010
Location: L.A.
Age: 52
Posts: 561
Originally Posted by Sailvi767 View Post
A aircraft with uncommanded trim does not pitch uncontrollably nose down. As the trim motor adds nose down trim up elevator can compensate until the stabilizer overpowers the elevator. At that point the nose will start down. Normally it’s a smooth progression unless the aircraft is on autopilot.
Says someone who has never flown the 737.

The 737 may have hydraulic power assist to the controls, but please do not think of this as the equivalent of power steering on a car. To counteract the MCAS trim forwards you need to pull with some 60 kg of force, using both control columns, to stop the aircraft nosing into the ground. If you are not prepared for that, or you are busy with something else, you are going down....

Originally Posted by GotTheTshirt View Post
Is there some logic in having a couple of switches operating in the opposite sense to the rest ??
It was a deliberate ploy by Boeing, to confuse everyone.
A bit like placing the fire handles (and fire warning lamps) out of your field of vision - to confuse you even more.
(The fire handles were originally on the coaming, in front, but Boeing needed somewhere to put the MCP on the classic series. So rather than designing a new flightdeck, they shoved the fire handles on the center panel, where you cannot see them, nor easily access them. The 737-Max still has the standard B-707 and 727 flight deck.)

Silver

Last edited by silverstrata; 11th Mar 2019 at 17:09.
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