One of the theories is that Shah waited until his co-pilot went to the bathroom, refused to unlock the door from there, and then de-pressurized the cabin so that they all died which left him as the only person alive on-board.
I'm sure there has been a lot of thought put into this locking mechanism so that hijackers can't access the cockpit, but how about the rogue pilot scenario like this one? IIRC, pilots outside can enter a code to unlock the door but it can be rejected by the person inside (so it really only applies if they're incapacitated)
EDIT: it appears some airlines mandate at least two people in the cockpit at all times after the 2015 Germanwings incident.
I thought it was standard procedure to have a flight attendant in the cockpit during bathroom trips since the germanwings disaster to prevent exactly this, until I realized germanwings was after MH370.
Simon did an update earlier this year on the Germanwings accident. He states the official report is flawed. It's an interesting read, but also quite sad that such basic questions are not answered and thus far few seem to even care that they get answered.
I'm sure there has been a lot of thought put into this locking mechanism so that hijackers can't access the cockpit, but how about the rogue pilot scenario like this one? IIRC, pilots outside can enter a code to unlock the door but it can be rejected by the person inside (so it really only applies if they're incapacitated)
EDIT: it appears some airlines mandate at least two people in the cockpit at all times after the 2015 Germanwings incident.