Try doing a 4-point hesitation roll in a Chipmunk, or any carburettor-engined aircraft. Cuts off fuel to the engine when inverted, no power produced but continues turning. When back in positive g the engine springs back into life. Perfectly normal practice, and in any piston engine that is working correctly you can cut the fuel supply, the prop will windmill, and as soon as fuel is restored the engine will produce power again.