Right now my money would be on some kind of catastrophic controls failure, but don't know enough about 737 systems to speculate with any detail. On the other hand I am very confident in saying that this guy did it intentionally. Was probably his go to trick for scaring kids into silence.
I suggest you go back and look at posts 312 and 313. We do know (to the extent that the tracking and automated instrumentation was good, but I haven't seen anything to contradict it since), that the plane leveled out and started climbing before plunging back down. No way for that to happen if no one can reach the controls, therefore someone was at, or at least able to get, to the controls. Fine, since no one else will, I'll do the math: Flight was fairly near its ending, so we have a mass between 41000 and 66000 kg, i'm guessing around 60000 kg for a ¾-full flight. Cruise thrust is, according to the Smithsonian Institute, about 20-30% of max takeoff thrust for this kind of 737. Again, we can assume the lower end of the range, say 22%. Max takeoff thrust is 121kN/engine. So we have 53 kN of thrust at the time the plane started to dive. By F = ma, the plane would have been diving at (assuming negligible drag)... wait that's only 0.88 m/s/s, (plus gravity, but you don't feel that in free fall). That's not enough to pin anyone against a bulkhead once the pitch is complete. Some of the data from post 312 indicates something slightly faster, at 2.69 m/s/s acceleration (plus gravity) over 10 seconds, which is slightly above that, but within the 20-30% range with a slightly lighter craft. And then checking the next data point, it's clear that thrust was increased considerably. Not sure if that's just because thicker atmosphere = more oxygen = more thrust with the same fuel, or if additional fuel was deployed, but damn. I don't know enough about jet propulsion to figure out what math to do from here to disambiguate.
They've found the black box, so hopefully that'll shed some light on things. https://www.bbc.co.uk/news/world-asia-china-60792827
Does the black box also include the cockpit voice recorder or is that separate. The cockpit recorder could be the key to this...or not...
Planes, as I recall, have multiple black boxes and I think that there's redundancy in what they carry, so that if only one of the boxes survives, they still have everything that's recorded. I mean, it's not like data storage systems have to be massive items anymore, so it certainly seems probable that they'd have enough space to hold a few terabytes worth of data (assuming that they needed to store that much).
IIRC when cockpit recorders were first installed they only recorded on a loop of about 30 minutes, which was usually a big help in most cases, but not enough in others. I think the current generation records a lot more of the cockpit chatter.
Doesn't look like the investigation has been made public yet, so I guess the Chinese feel it was a pilot issue and not a plane issue? Because with Boeing, it's usually a safe bet that it's the plane.
Transport Canada orders Boeing 737 jet operators to limit use of anti-icing system amid safety concerns Jesus. Just shut this company down already.
Alaska Airlines grounds all Boeing 737-9 Max planes after window appears to blow off in flight, forcing emergency landing Whoops!