Originally Posted by
Lookleft
James is a great story teller and has had quite an aviation career but an accident investigator he is not. The biggest flaw in the Analysis Recap is that the Captain disconnected the autopilot to turn back to Malaysia in response to a significant smoke fumes event. I very much doubt that an airline Captain would be disconnecting the autopilot and turning it at flight levels, particularly if the cockpit is filling up with smoke.
The Safety Investigation Report released in 2nd July 2018 actually concluded the autopilot was disengaged to make the turn back from IGARI. This was concluded on the basis that if the autopilot was making the turn, the angle of bank would be limited to 25 degrees. The turn however was at a higher rate of turn requiring an angle of bank of between 30 to 32 degrees. How did the investigators work out the required rate of turn? The turn back was actually seen on military primary radar.
I totally agree that any pilot flying at FL350 would have preferred to leave the autopilot engaged to make this turn. So, the question remains as to why would the turn be made with autopilot disengaged? Perhaps the pilot had no choice but to manually fly the aircraft because the automation failed? If the automation failed, then did something break to cause the failure? If so, what?