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Old 26th Jan 2023, 21:18
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soarbum
 
Join Date: Oct 2020
Location: Cork
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Originally Posted by Loose rivets
Fair comment, though there was plenty of time after MCAS played a role, for the mental chaos to become all-consuming.
I've long wondered if the power was left high because of being in a bewildered state, or if they imagined pulling the power back would exacerbate the pitch problem.
You have to remember that the auto-throttle was engaged and the crew had delegated the speed control to HAL. With the stick shaker going and a multitude of alarms distracting them, it was harder for them to notice in time that HAL wasn't doing his job.

From ET-302 Interim Investigation Report - p13
"At 05:39:42, the crew engaged Level Change mode and set MCP speed to 238kt"

Description taken from piece by Seattle Times, March 7th 2021

According to the interim investigation report released a year ago, the faulty Angle of Attack sensor on Flight ET302, even before it triggered MCAS to push the plane’s nose down, interfered with other sensor readings of altitude and airspeed. Registering the plane as still below 800 feet above the ground even after it passed that threshold, the jet’s computer had the autothrottle maintain full takeoff thrust for 16 seconds after it should have reduced the power for the climb phase. More significantly, seconds later the pilots set the jet’s speed target at 238 knots, but the autothrottle didn’t follow through. Again because of the faulty sensor on the left, the flight computer detected the discrepancy between the left and right airspeed values and flagged the data as invalid. Unable to validate the aircraft’s speed, the computer stopped sending thrust instructions to the autothrottle. As a result, the engines remained at maximum thrust for the rest of the fatal flight. The plane eventually exceeded the 737’s maximum design speed of 340 knots. This so increased the forces on the jet’s tail that the pilots couldn’t budge it manually.
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