I was reading on here about a guy who was starting up his Phantom. Suddenly one motor stopped and the prop flew off. I think it was a bad esc and the sudden stop on the engine caused the prop to un-self-tighten. I believe it was on the ground and nothing serious happened. But that got me thinking. What if your bird is up at 400' and suddenly one motor fails? Will it be able to remain airborne on just 3 engines like a 747 and limp home? Or is that pretty much the end?