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Old 6th May 2019, 04:57
  #4977 (permalink)  
Join Date: Dec 2015
Location: Cape Town, ZA
Age: 58
Posts: 419
Originally Posted by OldnGrounded View Post
From today's NYT:
Boeing Believed a 737 Max Warning Light Was Standard. It Wasn’t.

AOA disagree, of course. Sheesh.
Thanks for the link. It gets worse:
When Boeing explained to pilots in one meeting how systems on the Max worked, the company said that the disagree alert would function on the ground. In the late November meeting, Boeing told pilots for American Airlines (which had bought the add-on) that their disagree alert would have notified them of problems before takeoff.

“We were told that if the A.O.A. vane, like on Lion Air, was in a massive difference, we would receive an alert on the ground and therefore not even take off,” said Dennis Tajer, a spokesman for the union representing American Airlines pilots. “That gave us additional confidence in continuing to fly that aircraft.”

But in the last several weeks, Boeing has been saying something different. Mr. Tajer said the company recently told American pilots that the system would not alert pilots about any sensor disagreement until the aircraft is 400 feet above the ground.
My emphasis added. This is a critical point that was touched on previously. It is impossible to get a reliable AOA value until there is significant forward airspeed. Plus it takes time to compare the two values, and trigger the AOA disagree warning. By then the aircraft is airborne. Its a bit too late. If it was fitted and worked, which it didn't.
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