The New York Times is reporting that in tests over the weekend pilots from a number of U.S.-based airlines gathered at Boeing’s simulator center in Renton, Washington, to see if they could save the day in scenarios similar to those encountered by the pilots of the doomed flight of Lion Air 610 (and very possibly Ethiopian Airlines 302). In both cases the pilots apparently encountered trouble controlling the new 737 Max aircraft they were flying and in both cases the planes crashed catastrophically killing all aboard.
What did the tests determine? Well, nothing that we hadn’t suspected, but it was confirmation that the pilots in the Lion Air, who were clearly fighting against time in trying to get the jet under control, had very little time indeed to do that.
The tests showed that if the pilots didn’t counteract the system immediately, they had a mere 40 seconds before the plane’s MCAS system, designed to prevent the aircraft from getting too slow, would instead put the plane into an unrecoverable dive. The Times quoted pilots as saying that the system’s effect on the flight controls was surprisingly strong. The system, which will trigger repeatedly even after the pilots try to correct the nose-down condition, was updated by Boeing late in the certification process to apply more powerful nose-down trim than had originally been planned and to repeat that correction if the sensor continued to erroneously report to the system that the plane was getting too slow.
Every pilot who flew the doomed flight’s scenario was able to recover control, but it should be emphasized, as the Times did, that this was only after they have been made aware of the issue and how to fix it. And even then, they expressed surprise at how much pressure it took to raise the nose again after they’d successfully turned off the MCAS system, which the Lion Air pilots never succeeded in doing.
It’s been a popular response from pilots, especially those without airline experience, to blame the pilots of the two fateful flights for not being able to recover from the severe nose-down flight attitude they were encountering and the powerful nose-down control forces, forces which at their extreme throw were unrecoverable, the tests showed. But the truth is that the pilots in the test were challenged to recover control even with full knowledge of the system.
The pilots of Lion Air 610 and most likely Ethiopia 302, had no training on the system and, in fact, were probably not even aware of its existence.
The Times also reported that the pilots were all able to successfully recover the plane in simulator flights of “planes” using the updated software, which Boeing plans to release soon, along with updated training manuals and materials.
The company will also, reports have indicated, include a second sensor’s reading so the system could compare the two and not activate the nose-down trim if there were a miscompare between the two readings, a system that might have prevented MCAS from taking control of the plane from its human pilots.
Read more Plane & Pilot coverage of the ongoing 737 Max crisis