The fuel level indication system in the simplest form is a transparent window on the tank side and in its usual application a float-driven potentiometer installed in the tank . After the TWA Flight 800 disaster , a revision was made to aircraft fuel systems to address the potential explosion hazard of electrical components located in the fuel tank . Single-engine piston aircraft fuel level systems moved to utilize float level gauges from the CNG and LPG industries which had the float drive a magnetic coupling and relocated the potentiometer outside the fuel tank
TWA Flight 800
TWA Flight 800
Aircraft fuel system