An exclusive look inside a Boeing flight simulator with two American Airlines pilots trying to help correct the software flaw believed to be behind two crashes

After takeoff, the Boeing 737 suddenly warns pilots that the plane is about to lose lift and stall, an erroneous signal from a bad sensor. The control column shakes, loudly. Pilot Roddy Guthrie diagnoses the problem—and then the plane’s nose suddenly pitches down, on its own. Emergency No. 2.

He pulls back on the control column to keep climbing and gets the airplane back to the proper orientation, nose up. But it happens again, with more force. And then a third time, with even more force, so that he’s looking almost straight down at the ground—the most terrifying sight for any pilot.

The episode, a repeat of the system failure suspected in two Boeing 737 MAX crashes, takes place in a Boeing full-motion flight simulator Wednesday morning. A few minutes later, Capt. Guthrie and another pilot try again, this time with Boeing’s proposed software fixes installed—software that’s critical to Boeing, airlines and travelers world-wide.

Excerpt from WSJ
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