According to the flight instructor and the pilot-rated student, both believed the Piper PA 18-150 had been fueled at the time it was pulled out of the hangar by line personnel, and they both observed a fuel truck parked near the airplane prior to the flight.
The student had performed the preflight inspection, during which he interpreted the fuel sight gauges as indicating full fuel, however he did not visually check the fuel in the tanks.
When the instructor arrived at the airplane, he asked the student how much fuel was on board and the student said the tanks were full.
The flight departed from Lynchburg, Virginia, and made several takeoffs and landings at a nearby airport.
About an hour into the flight, as the plane was 1,000 feet above ground level, the engine lost all power.
As the instructor began a turn toward a nearby pasture, the engine started producing power again and the instructor chose to continue the turn, heading toward the nearest airport. The engine then lost all power again.
No longer able to glide to the nearby pasture, the instructor flew the airplane straight ahead and let it settle into the trees. The airplane struck the trees and terrain and came to rest inverted near Brookneal, Virginia.
Examination of the wreckage by an FAA inspector revealed substantial damage to the wings and fuselage.
The inspector recovered about one pint of fuel from each fuel tank.
After the accident, the flight school held safety briefings with its instructors, faculty, and students. These briefings included discussion of the circumstances of the accident, and the implementation of policy changes related to pre- and post-flight responsibilities of students and instructors, new fuel level measuring procedures, and dispatch records of fuel status. These changes were applied to all airplane types and operations at the school, and were subsequently written in the Flight Operations Manual.
Probable cause: The flight instructor and pilot-rated student’s inadequate preflight inspection, which resulted in a total loss of engine power due to fuel exhaustion.
NTSB Identification: ERA15CA120
This February 2015 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Your best fuel gauge is free at your local lumber yard. It’s a wooden yard stick cut to a one ft. length.
As an old and not so bold pilot once said, “the only time you have too much fuel is when you are on fire”!
Have fuel gauges become so unreliable that they are either ignored in flight or the amount of fuel indicated is dismissed as inaccurate and the quantity remaining assumed to be more than enough to complete the flight? I’m not familiar with the PA-18 but if the fuel quantity in each wing tank is visually available with sight gauges in the wing roots did anyone bother to look at those gauges anytime during the flight? The only reason a piston engine equipped airplane flies is because the engine runs and turns the propeller to pull (or push) the airplane through the air. And the only reason the engine runs is because it has fuel to power it. What can be more important than the amount of fuel on board while airborne? It has to monitored continuously. If the quantity gauge is in error then get it repaired before next flight.
It never ceases to amaze me the number of fuel exhaustion cases that bring down airplanes. Quite frankly I can’t understand it. If there’s one thing I make certain of every single time it’s how much fuel is in the plane. Perhaps as fuel has gotten more expensive we tend to keep less of it in our tanks to keep weight down. If you’re worried about the cost of the fuel versus the weight maybe you shouldn’t be flying. You can’t afford to fly in one way more than another.
“Trust, but VERIFY” really applies to any fueling operation. It’s incumbent on the PIC (in this case the CFI) to assure the student took appropriate steps to verify quantity, fuel type, fuel purity. Those are all essential parts of every pre-flight. “Verify” means a visual check plus a dip if less than to the neck. I think it was as much poor procedure by the student, and a lack of supervision (i.e. the CFI asking “Did you look into the tanks?”) that was as much a root cause of this accident as the fact the engine quit at an inconvenient time. I’ve found water in fuel tanks, and also sediment. A couple of years ago a fatal accident on my home field followed misfueling by a poorly trained lineman (Jet-A does not burn well in a piston engine designed to use 100LL!). Water and sediment we test for by drawing the FAA recommended 8 oz sample from each drain. Rock the wings first and wait five minutes or so. See water or sediment in the fuel sample??? Discard the sample and draw more fuel from each drain until it’s clean. Note the stance of the aircraft. Tail draggers sit, well – tail low! It may not be possible to get a good fuel sample from some conventional gear aircraft without placing the tail on a block. The low tail and inappropriate location of quick drains caught an acquaintance a few years ago. His engine didn’t run very well on the water that got into the tanks undetected from an overnight rain storm. The test for Jet-A is just as easy – dribble a few drops on a piece of white paper and allow it to dry. See a greasy spot on the paper? … DON’T FLY!
Most light aircraft have fuel tanks that can be visually inspected. The PA28 series can easily be inspected. The Piper Super Cub PA18-150 uses sight gauges in the wing roots. The fuel truck and expectation can cause such gauges to be misread.
Some airplanes have the fuel filler located near the wing tip and unless the tanks is really full fuel cannot be seen. The Beech King Air main fuel tanks are like that. But the nacelle tank on the BE90 prior to the F90 does have a removable fuel cap so at least the nacelle can be visually checked. The BEF90 and BE 200 has a screwed down cover over the fuel cap making visually inspecting the nacelle difficult. The BE300/350 have an optical low fuel warning in the nacelle tank that is very reliable. But the main fuel tank does not have a visual check except for full..
Large aircraft often have a drip gauge which allows checking the fuel level in a tank by lowering a tube until fuel is above the level of the tube.
Actually watching your plane being fueled so you can verify the correct grade/kind of fuel and the quantity was really dispensed is always teh best practice. At least verify the fuel order was delivered.