Definition

A Magnetic Fuel Level Indicator (MFLI), also sometimes called a Mechanical Fuel Level Indicator, is a calibrated measuring rod built into aircraft fuel tanks that provides a backup method of measuring fuel quantity.

Description

An MFLI allows direct reading of fuel quantity when the aircraft is on the ground. Typically, they are installed in multiple locations in aircraft fuel tanks, and personnel access the indicators from underneath the wings. For example, on the Embraer 170, there are three MFLIs under each wing. On the Airbus A318, A319, and A320, there are four MFLIs under each wing and one per center tank.