In aircraft with several fuel tanks, what prevents the fuel supply in one tank from being exhausted before switching tanks?

In aircraft with multiple fuel tanks, the primary mechanism that ensures fuel is supplied evenly from different tanks is the fuel selector switch. This device allows the pilot to choose which fuel tank is supplying the engine, thus preventing any single tank from being depleted before another tank is accessed.

The fuel selector switch facilitates controlled management of the fuel supply, enabling the pilot to monitor and switch tanks as necessary. This practice not only ensures that fuel is consumed evenly but also minimizes the risk of running one tank dry, which could lead to engine performance issues or failure.

While the fuel pressure warning signal system may indicate low fuel pressure, it does not actively manage fuel distribution between tanks. Similarly, engine fuel pump bypass valves and fuel pressure relief valves serve their specific functions in maintaining pressure and managing excess flow, but they do not regulate how fuel is drawn from multiple tanks. In summary, the fuel selector switch is essential for the proper operation of an aircraft's fuel system, ensuring balanced fuel consumption across multiple tanks.