Re(6): 737 Max Crash Posted on 3/16/2019 at 18:25:15 by Bill Hoover 11th
US Airlines have had 40,000 flights with the 737 max with no problem. US Airlines do not engage the auto pilot until at a very safe altitude. For United Airlines that is 18,000 feet for the 777 and for the 737 10,000 feet.
Many foreign Airlines engage the auto pilot on take off(I believe that is the case with the two recent 737 max crashes). Boeing says the the 737 max is certified do that. However some foreign airline pilots may not be trained to recognize deviations from flight.
As the airplanes nose comes up on takeoff the angle of attack and the airspeed may be such so as to cause the auto pilot think is approaching a stall and push the nose down to correct the stall. As the nose goes down the ground collision avoidance system thinks it going to crash and commands the auto pilot to pull up and the aircraft gets into a porpoise situation. If the pilot does not recognize what is going on and disengage the auto pilot or over override it manually the aircraft will enter a "fugoid" situation and go out of control.
If the the 737 max was fundamentally unsafe, the US Airlines and the US Pilots Association would have been all over the FAA to ground it long before 40,000 flights. There may also be a center of gravity issue created by the installation the of the bigger engines on the 737 max that makes recovery from outside the normal flight envelope more difficult.
My information comes from a United 777 Captain who is also a Major General in the Air National Guard.
Now that the 737 max is grounded worldwide the issue will be very clouded with legal,liability,political,technical and competition factors that will obscure the safety investigation.
