Fuel Guage Issues May Result In Fuel Exhaustion

The FAA has issues a Special Airworthiness Information Bulletin (SAIB) directed to owners and operators of Enstrom Helicopter Corporation-manufactured (Enstrom) 280 FX helicopters of a false fuel quantity indication with subsequent risk exposure to fuel exhaustion during flight. At this time, the FAA feels this airworthiness concern is not an unsafe condition that would warrant an AD.

File Photo

There has been a report of a helicopter accident that occurred after fuel exhaustion. Investigation revealed a false “Full” fuel quantity indication on the fuel indicator as contributory. This false reading was due to the fuel level sending unit wires being disconnected. A false fuel quantity indication of “Full” results when the fuel level sending unit wires are disconnected at the “wristlock” located between the tops of the left and right fuel tanks, with the master switch in the “On” position.

The FAA recommends that prior to each flight the visual check specified in the flight manual be performed to verify fuel quantity in the fuel tank. When the fuel tank is “Full” the fuel quantity indicator in the cockpit should read “Full.” If the fuel quantity in the tank is less than “Full” and the fuel quantity indicator reads “Full” then the fuel indicating system should be serviced per the maintenance manual to correct any noncompliance. Additionally, a visual check of the “wristlock” is recommended during each Periodic Inspection to ensure the plastic covers over the “wristlock” connections are tie-wrapped in accordance with the maintenance manual.

FMI: SAIB