[Sax]

So the prevailing theory is now this?:

* Co-Pilot and/or Pilot lock cabin door (either alone, or both)

* ADS-B/Transponder off

* Manual Pressurization ON, Outflow valve OPEN - Cabin depressurizes during extreme maneuvers - dive/climb. (Everyone in cabin dead after a short time.)

* Repressurize

EITHER:

* Some point prior to landing, ACARS OFF (no wheels down text to Rolls Royce)

OR

* Crash into the sea

Either way - INMARSAT pings continue until landing or crash.

Is it really that easy for someone locked in the cabin to kill everyone on board an airliner?

[Fai Mao]

If they were going to crash the plane there would be no need to kill the passengers by gaining and losing altitude.

If the passengers were killed first the idea was to capture the plane