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Subject:  737 MAX - More Details on the MCAS System Date:  3/20/2019  2:32 AM
Author:  AjaxofTelamon Number:  555201 of 603657

A new clip on YouTube explains in more detail the problem with the MCAS system on the 737 MAX 8.

Keep in mind as you are reading this that the MCAS is mainly used by military jets, the 737 MAX pilots did not have any training or knowledge of the MCAS system and that the original FAA design - on this completely unknown to the pilots system - specified a limit of 0.6° elevator down movement producing no more than 5° Nose down movement.

After the Lion Air Crash, Boeing revealed a different set of numbers on the MCAS system, namely that "the elevator down movement was 2.5° and not 0.6° as the original FAA design specification (About 400% higher than the specification).

So, if an input 0.6° elevator down was producing a 5° nose down movement (Original FAA design) then an elevator down movement of 2.5° will produce over 20° of Nose down movement - assuming a linear relationship between the two.

According to Boeing, each time the MCAS was triggerred, the MCAS system added an extra 2.5° degrees of movement.

So, the second time around, the MCAS will give the elevator a down movement of 5° with a corresponding Nose down movement of over 40°

And by the third or fourth MCAS intervention the 737 is in a vertical position, nose down, heading for the ground.

More from here 5:08 minutes

The 737 MAX 8 is not a safe plane, the MCAS is not a safety feature and we are lucky we did not experience more crashes.

From the comments:
Chilling video. This plane should have never been approved.
Big new engine + same old body + unbalance
So + MCAS = off balance and crash
I wonder if the software programmer of MCAS is a pilot.

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