07-24-2025, 04:24 PM
(07-24-2025, 03:30 PM)sahgwa Wrote: How about both? if you don't mind.
In this specific case the evidence is pointing to the cutoff switches being moved.
In the ANA case in 2019, the computer hadn't changed over to ground mode yet when the crew activated reverse thrust, and went to power to use reverse to help slow the aircraft. Since the computer was still in air mode, it read the rapid increase in thrust as a runaway engine condition. The TCMA (Thrust Control Malfunction Accommodation) activated and initially rolled the power back, then shut the engines down to protect them. It was found that the computer parameters were wrong, so the TCMA was reprogrammed as a result. That was the only incident where that happened that I'm aware of.
It's possible that an EEC (Electronic Engine Control) of FADEC (Full Authority Digital Engine Control) failure could cut off fuel to one or more engines.
There was a SAIB (Special Airworthiness Information Bulletin) sent out after two 737 fuel cutoff switches were found to have the locking mechanism installed incorrectly, but it the part number is different (766AT613-3D for the 737, and 4TL837-3D for the 787-8 and -9) and the accident aircraft had the throttle quadrant and fuel cutoff switches replaced twice after the SAIB was issued.




