Regardless of the motion of the door in opening, you can count in there
being pressure sensors that block the locking mechanism from actuating
when the pressure in the cabin is higher than external pressure...
They don't all have to be electrical to still be safe in case of total
electrical failure... A simple bellows mechanism, no different from
your altimeter, can push a locking pin into the doors hardware anytime
the inside pressure exceeds the external pressure...

denny