What is one consequence of a malfunctioning fuel vent system?

A malfunctioning fuel vent system can lead to the formation of a vacuum in the fuel tanks. This occurs because the fuel system is designed to allow air to replace the fuel being consumed. When the vent system is not functioning properly, air cannot enter the tank as fuel is drawn out, resulting in a decrease in pressure inside the tank.

This vacuum effect can restrict the flow of fuel to the engine, potentially causing fuel starvation. This situation can hinder engine performance, affect fuel delivery, and if unchecked, may lead to engine failure. Thus, understanding the importance of a properly functioning fuel vent system is critical for ensuring reliable fuel delivery and overall aircraft safety.