4 ms·
"Runaway stab trim". It is a memory item, every pilot should be able to perform it from memory. Turn off the motor, and the trim is manual. There is a crank
by 9659 3y ago
"Runaway stab trim". It is a memory item, every pilot should be able to perform it from memory.
Turn off the motor, and the trim is manual. There is a crank right there in the cockpit. If it is too hard to turn, change aircraft configuration to reduce the forces required to. Pilot know how to do this. This pilot stuff, they understand the forces on the flight controls and what impacts them.
Boeing made an engineering mistake. The pilots also made an operational mistake. Unfortunately, both mistakes at the same time were fatal.
I pray that pilot training has improved. And that Boeing has made systems level changes to the aircraft that will preclude it happening in the future.
And that is how aviation becomes safer every year; at a significant cost of customers lives.
- ethbr1 3y ago> And that is how aviation becomes safer every year; at a significant cost of customers lives. "Significant" might be inaccurate. It looks like FAA Part 121 accidents over the last 10 years with fatalities have been... 4. [0] For a total of 6 fatalities. [0] https://www.ntsb.gov/Pages/AviationQueryV2.aspx https://www.ntsb.gov/Pages/AviationQueryV2.aspx; 2018 (1 passenger fatality) https://www.ntsb.gov/investigations/Pages/DCA18MA142.aspx https://www.ntsb.gov/investigations/Pages/DCA18MA142.aspx ; 2019 (3 crew fatalities, cargo flight) https://www.ntsb.gov/investigations/Pages/DCA19MA086.aspx https://www.ntsb.gov/investigations/Pages/DCA19MA086.aspx and (1 passenger fatality) https://www.ntsb.gov/investigations/Pages/DCA20MA002.aspx https://www.ntsb.gov/investigations/Pages/DCA20MA002.aspx ; 2022 (1 ramp fatality) https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106517/pdf https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/G...
- WalterBright 3y agoThat low accident rate is nigh inconceivable. It's an incredible achievement.
- ethbr1 3y agoThe fatal accident count is higher for GA, but I didn't normalize against flight hours or flights, just glanced at it. I'm sure there's been a study somewhere that attempts to untangle all the factors that differ between commercial carriers and GA, to see which safety is most sensitive to -- continuous highly professional maintenance, highly trained and experienced crew, rigorous airliner certification regime, etc.
- kennethrc 3y agoOne of which (Atlas Flight 3591) was Pilot error: > The probable cause of this accident was the inappropriate response by the first officer as the pilot flying to an inadvertent activation of the go-around mode, which led to his spatial disorientation and nose-down control inputs that placed the airplane in a steep descent from which the crew did not recover.
- SAI_Peregrinus 3y agoBoeing also reduced the size of the manual trim wheels, which let them become impossible to turn sooner than on previous 737s.
- WalterBright 3y agoThe electric trim switches override MCAS. This was explained in the Emergency Airworthiness Directive sent to all MAX pilots after the first crash. Also, overspeeding the airplane makes it much harder to turn the manual trim wheel. The cockpit voice recorder on the EA flight recorded the overspeed warning horn, which the crew did nothing about (they were at full power, should have pulled the throttles back). The LA crew restored normal trim twenty-five times before crashing. What they never did was turn it off after restoring normal trim.