A device to measure both the fuel level in high wing aircraft fuel tanks and check for water and other impurities in the fuel tanks. This invention is used from the underside of the wing and is inserted from below into the fuel tank sump valve. The device measures both the height of the fuel within the tank to determine how full it is and at the same time drains fuel into the device for visual inspection of water and other impurities. The device can be used to determine both fuel level and impurities at the same time or separately.
