"Five of the 11 faults were related to the uncommanded autothrottle disengagements, with the first being logged at 11:04 UTC. At that point, the TUI Airways aircraft was on the runway at BRS at the beginning of its takeoff roll.
The AAIB said the fault record indicated that the suspected cause of the uncommanded autothrottle disconnect was ASM 1, the autothrottle servo motor for the number 1 engine throttle lever. Four further disengagements happened on the flight to LPA, with two during the initial climb phase."
"Boeing has said that the autothrottle system on the 737 NG has had a long history of “nuisance disconnects” during takeoff engagements. When the fault history is checked, it often shows a problem with the ASM for either the number 1 or 2 lever, with subsequent checks typically showing no faults."
"According to the investigators, the TUI Airways Boeing 737-800 was equipped with older ASMs. In October 2021, Boeing issued a Fleet Team Digest to airlines operating the 737 NG, detailing the problem and the service bulletin to replace the ASMs and apply the required flight control computer software."
sourceOh I get it - you have to buy a new autothrottle system at your leisure, it's your problem not Boeing's - until people get killed.