What is the risk of allowing the fuel in one tank to become exhausted before changing over to another tank?

Allowing the fuel in one tank to become exhausted before switching to another tank poses a significant risk of loss of engine power. This situation occurs because when one tank runs dry, the engine loses its fuel supply from that tank, potentially leading to an abrupt cut in fuel flow to the engine. This interruption can stall the engine, especially if the switch to the second tank is not timely or if there are complications in fuel transfer or consumption rates.

Maintaining fuel in both tanks and ensuring a timely changeover helps prevent this risk. Additionally, modern aircraft are often designed with fuel quantity indicators and warnings that alert the pilot to the fuel levels, emphasizing the importance of monitoring fuel reserves actively and making transitions before reaching empty to ensure continuous engine operation.