Out of gas?


Have you ever found yourself a little short on fuel and had to sweat it out until landing? Not fun.

With our weight limited aircraft, how much fuel to carry is a balancing act. Then of course we get headwinds or weather diversions and fuel becomes a concern.

The Grumman GA7 Cougar aircraft was approximately 12 miles from the destination airport when the pilot reported that the left engine had failed. Three minutes later, the pilot reported fuel exhaustion with both engines out. The pilot attempted to land the aircraft on a dirt road but the aircraft stalled during the attempt. The aircraft struck a ditch next to the roadway and was substantially damaged. The pilot and passengers were wearing their seatbelts and were uninjured. The aircraft encountered stiffer than expected headwinds.

The Piper Cherokee PA-28-140 aircraft on a VFR flight was approximately 28NM east of the airport when the pilot requested the Winnipeg TCU Controller to give a direct route to the airport as they were low on fuel. Shortly thereafter the pilot declared an emergency and attempted a forced landing near the shore of Lake Superior. Two persons were extricated from the wreckage which was upside down and partially submerged in the water. One person was injured and the other fatally injured. 

A Cessna 172 with four people on board was on a VFR flight when the pilot reported an engine failure and landed on a road.  The aircraft departed with an estimated 2.8 hours of fuel on board. When the engine failed, the aircraft had been flying for 2.6 hours and both fuel gauges read 1/4 tanks. 

A Cessna 180 on a 413 mile VFR flight ran out of gas. The pilot force landed safely 13 NM short of his destination. The pilot had fuelled the aircraft for the flight with approximately 1 hour of fuel reserve. During the flight the fuel gauges began to run down faster than expected and approximately 35 minutes from the destination the gauges read empty. Approximately 15 NM north of his destination the pilot initiated a precautionary landing on a gravel road. During the descent the engine sputtered and quit. Upon examination of the aircraft, the left inboard fuel cap was found to be off and hanging by its chain. It is believed that the loose or missing fuel cap had allowed fuel to be siphoned from the tank during flight.

The pilot of a Cessna 172M aircraft was practicing circuits when the aircraft's engine sputtered and failed during the take-off portion of a touch-and-go. The pilot elected to land the aircraft straight ahead on the remaining portion of runway 28, however, the aircraft did overrun the available remaining runway by about 100 feet. 

The aircraft was reported to have about 1/4 fuel on board with less than 1/8 in the right hand tank. No mechanical fault was found with this aircraft. More fuel was added and it was fine.

The Kenora FSS received a "Mayday, Mayday - Engine Failure" from a float-equipped Cessna 180J aircraft. The aircraft pilot subsequently advised that he had landed on a small lake without further incident. He was one mile short of his destination.

The company owner advised that the left fuel tank was found empty but that the right tank contained 10 gallons of fuel. The operator believes that the empty fuel tank was selected instead of the "Both" selection recommended by the operator.

If we run into headwinds or weather diversions, we need to decide early on how much fuel the winds or diversions may cost us. We may need to decide to land en route to refuel or turn around and return to out departure point. If we wait too long like the Cougar and Cherokee pilots, the results could be disastrous. We tend to want to keep to our original plan even when new information indicates an alternative may be wiser.

We should always know how much fuel is on board time-wise. Cessna gauges are notoriously inaccurate. The gauges should be frequently checked against the time flown. We should be suspicious of gauges that read high or we could end up like the first C-172 pilot.

We should also be concerned if the gauges start reading considerable lower than we expect. The problem could be a leaking fuel cap or one that has been left off as happened to the C-180 pilot.

Fuel gauges that are reading lower than we think they should read may be due to not correctly leaning the mixture.

The second C-172 and the C-180J pilots had very little fuel in one tank. An old Cessna Service Bulletin states that when the fuel is selected to “Both” and one tank goes dry, an airlock may occur, preventing fuel from being supplied from the other tank. We should select one tank at a time when we have less than 1/4 fuel remaining. If an engine sputters, we can quickly switch to the other side. When the tanks are this low, I recommend that the fuel be switched from one side to the other every 10 to 15 minutes.

We should also watch for large fuel imbalances and try to equalize the fuel in each tank. We need to monitor the fuel in each tank when we have one side or the other selected so that we don’t let one side run dry. If one side does run dry, we should immediately select the other side. Many schools teaching pilots to fly Piper aircraft advocate switching fuel tanks every 1/2 hour.

We owe it to ourselves and our passengers to be cautious about fuel. Flying is supposed to be fun. Sweating out the fuel in the final stages of a flight is not fun. An accident is even less fun.

Dale Nielsen is an ex-Armed Forces pilot and aerial photography pilot. He lives in Abbotsford, B.C., and currently flies medevacs from Victoria in a Lear 25. Nielsen is also the author of seven flight training manuals published by Canuck West Holdings.

Got an aviation safety story to tell? Dale Nielsen would like to hear from pilots who have educational aviation experiences to relate. Excerpts from these stories will be used in upcoming safety articles. Dale can be contacted via e-mail:  dale@flighttrainingmanuals.com.