During negative-G flight, the flip-flop valve provides the engine access to which fuel source?

The correct answer, which is the collector tank, relates directly to the functioning of the flip-flop valve during negative-G flight conditions. In this scenario, negative Gs can cause fuel to move away from its intended feeding path in the fuel system. The engine requires a reliable fuel source to maintain operation, and that's where the collector tank comes into play.

The collector tank is designed to gather fuel that is directed toward it, ensuring that the engine receives a steady flow of fuel even when the aircraft experiences negative G forces. The flip-flop valve plays a critical role by switching the fuel supply to this tank, allowing the engine to continue operation without interruption during these adverse conditions. Thus, it is essential for maintaining engine performance when fuel may otherwise be displaced.

Understanding the function of the collector tank highlights the importance of this system in ensuring safety and reliability during all flight maneuvers, particularly those involving changes in gravitational forces.