Poor planning puts airplane in drink

Aircraft: Skybolt. Injuries: None. Location: Sarasota, Fla. Aircraft damage: Substantial.

What reportedly happened: About a month before the accident, the pilot added about 17 gallons of fuel to the bottom fuel tank. About 25 minutes into the accident flight, the engine experienced a total loss of engine power. The pilot ditched the airplane in the Gulf of Mexico, and it sank. The wreckage was recovered.

The post-accident examination revealed that the fuel tank contained four gallons of seawater and no fuel and that the fuel system had only trace amounts of fuel at the gascolator. According to the pilot and local authorities, no evidence of fuel leakage was found in the water.

According to fuel records and the pilot’s statement, it is likely that the plane had about 23 gallons of fuel on board at the last refueling, however, six gallons were in the top tank and used during taxi and run-up operations. Therefore, considering the airplane’s lowest fuel consumption rate of about 7.2 gallons per hour, the airplane would have been able to operate for 3.2 total hours.

According to excerpts from the Lycoming Operator’s Manual for the IO-360 series engine, at 2,400 rpm, the fuel consumption, depending on the mixture setting, would be between 43 and 82 pounds per hour. Investigators determined that at the time of the accident, the airplane had flown a total of 3.3 flight hours. Therefore, the pilot began the flight with an insufficient amount of fuel and did not monitor its quantity during the flight.

Probable cause: The pilot’s inadequate preflight planning and failure to monitor the fuel quantity during flight, which resulted in a total loss of engine power due to fuel exhaustion.

NTSB Identification: ERA13LA094

This December 2012 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.