[QUOTE=BuzzBox;11349618]Let's not confuse "fact" with "theory". The theory about a hand-flown turn back at IGARI came from a simulator study that was conducted during the official investigation. That study concluded the turn back was flown with the autopilot disengaged, because they could not replicate a turn flown by the autopilot with the turn that was observed on primary radar. IIRC, a subsequent study, that was not part of the official investigation, found the radar-derived position data used in the simulator study was inaccurate. The second study used ADS-B derived position data and determined the observed turn was well within the capabilities of the autopilot. So who's right?[/cQUOTE]
This has always been the problem with this investigation. Where do you go for reliable information?
The official report says the autopilot must have been off for the turn. As far as I know the only other report was from the IG who say they can replicate the turn by going to bank angle 25 to make the turn. I don’t understand or have seen a report using ADS-B as that was definitely not working during the turn….But also the continuing flight towards Penang is not straight, so the autopilot is looking like it is off here too. The most accurate study of the primary radar also shows a flight at no particular altitude(phugoid?).
So I would say it looks like the autopilot is not engaged.
Last edited by birdspeed; 17th Dec 2022 at 13:01.