The Boeing 737 Max is out of service around the world, following a fatal crash of an Ethiopian Airlines and an Indonesian Lion Air flight and there is intense investigation and speculation as to the cause of the crash.
Some suggest that pilots in poorer countries may have been inadequately trained to fly the new aircraft, but there also been a string of accusations that a key safety feature was not enabled on the plane that crashed, because Boeing had disabled it and sold access to it separately as an upgrade that poorer airlines might not have been able to afford.
The disabled system was used to resolve conflicting information from two different sensors, one that measured airspeed and another that measured the "angle of attack" (the direction the plane's nose was pointing in).
John Hansman, an aeronautics professor at the Massachusetts Institute of Technology, said the Ethiopian Airlines pilots clearly struggled to control the plane and might have been too preoccupied to realize whether the anti-stall system was malfunctioning.
"All you know is the airplane is not flying correctly. You're trying to figure it out at the same time you're trying to fly an airplane, which is difficult," Hansman said. He believes the crashes show the need for more pilot training, whether it is done on a simulator, a computer or an iPad, which is becoming more common at airlines.
Boeing to make safety feature standard on troubled Max jets [David Koenig and Tom Krisher/AP]