I already acknowledged this was a speculative line of thought. Don't think any air crash investigators are looking into a nobody on the internet for accident
clues, so it's a kind of very limited irresponsibility.
However there are actually not that many causes, that could explain the vertical drop either than, and in order of decreasing probability:
The accidental deployment of the reverse thrusters, is something
that requires multiple mechanical failures, is not supposed to happen
but Boeing already has a past history with it, although on a different model.
The Niki Lauda/Boeing controversy.
However there are actually not that many causes, that could explain the vertical drop either than, and in order of decreasing probability:
- Suicide/Terrorism
- A Jackscrew Mechanism Failure: https://www.wikiwand.com/en/Jackscrew
- Accidental Deployment of the Reverse Thrusters.
The accidental deployment of the reverse thrusters, is something that requires multiple mechanical failures, is not supposed to happen but Boeing already has a past history with it, although on a different model. The Niki Lauda/Boeing controversy.
"What if the reversers OPEN in flight?!"
Video at correct time: https://youtu.be/OguKthkuaT4?t=1026