One thing that would have to happen is to shut down the engines so people could safely move from one place to another on the tarmac. I don’t know how long the APU would hold out for once the engines are off.
wastedyears wrote: “I don’t know how long the APU would hold out for once the engines are off.”
The APU runs off the aircraft’s fuel tanks. Since it consumes far less than the main engines, it could probably run for days. They do consume some oil. I don’t know what would run out first, oil or jet fuel, but I imagine it would take quite some time.
As for being stranded, there is no reason whatsoever for stranding passengers for hours. There are several ways this could be dealt with...a return to the terminal (if there’s an open gate), using a staircase truck or stand and deplaning/shuttling passengers back to the terminal, and/or servicing the plane and providing food/water to the passengers. All airlines should have contingency plans for dealing with problems like this. Various responses should be automatically triggered depending on the length of the delay. Of course, that requires a degree of organization that seems to be missing these days. I travel fairly frequently, and the airlines seem to be in constant crisis management mode. They spend all their time stomping out fires rather than eliminating the causes of those fires. It seems very chaotic to me, but I’d love to hear an airline employee’s perspective.