DC-10 doors:
Sorry chaps, I am guilty of slovenly writing. What I should have said was "in the event of electrical AND pneumatic failure..".
To the best of my recollection the doors were normally operated(slides disarmed) by an electrical motor. In emergency mode (slides armed) they were operated pneumatically. If all else failed it was possible for two strong chaps to lift it.
I also seem to remember that it was possible to open 1L Door from the outside with a hand crank.