NTSB Factual Report

On April 14, 2001, at 1235 central daylight time, a Maule MX-7-180AC, N4261E, owned and piloted by a commercial pilot, received substantial damage on impact with terrain during a forced landing on a muddy agricultural field. The airplane experienced a total loss of engine power after takeoff from runway 17/35 (2,600 feet by 60 feet, asphalt) at the Buffalo Municipal Airport (8Y2), Buffalo, Minnesota. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 personal flight was not operating on a flight plan. The pilot and one passenger received no injuries. One passenger received minor injuries. The flight was en route to the Flying Cloud Airport, Minneapolis, Minnesota.

The flight departed from Eden Prairie, Minnesota at approximately 1100 en route to 8Y2 where the airplane received 8 gallons of fuel from Buffalo Aviation. The pilot reported to the Federal Aviation Administration (FAA) that he did not drain the airplane's fuel sumps after the airplane was refueled. The engine lost power on takeoff at an altitude of 300-500 feet agl.

On-site examination of the airplane by the FAA revealed that water was present in the fuel line leading to the engine driven fuel pump and one ounce of water was present in the fuel line leading to the electric fuel pump. The FAA inspected the fuel supply at Buffalo Aviation and found 1 inch of water at the bottom of the ground tank which was used to fuel the airplane. A sample of fuel taken from the fuel pump of the ground tank exhibited bubbles of water on the side of the sample jar. Additional inspection of the airplane's fuel system was performed on May 1, 2001 during which water was found in the fuel servo. During an FAA interview of the lineman who refueled the airplane at 8Y2, the lineman reported that it was his second day of employment at Buffalo Aviation and that he had not received training in the handling of fuel as it pertained to contamination . The owner of Buffalo Aviation stated that the line personnel receive training regarding the refueling of aircraft. Photos of fuel samples taken are included in this report.

The owner reported that the refueling tank's filter, filter canister and go/no go fuse were changed in January 2000.

Advisory Circular (AC) 20-125, Water in Aviation Fuels, states, "The responsibility for maintaining dry fuel should be recognized as a joint responsibility of the aircraft manufacturer, maintenance personnel who work on an aircraft, each person who handles the fuel from the refinery to the aircraft, and the pilot who flys the aircraft. The greatest single danger of water in fuel results from human error that allows fuel contaminated with water to enter an aircraft fuel system or permits an aircraft to be operated before its fuel system is properly checked for water. The possibility of human error can never be eliminated, but it can be minimized through careful design and maintenance of airport fueling facilities and fuel equipment and by good operating procedures, inspections, checks, training, and recurrent training of fuel handling personnel and flight personnel." AC 20-125 additionally states, "The pilot-in-command has the final responsibility to determine the aircraft is properly serviced. An important part of the preflight inspection is to drain aircraft fuel tank sumps, reservoirs, gascolators, filters, and other fuel system drains to assure that the fuel supply is free of water. A review of National Transportation Safety Board Briefs of Aircraft Accidents involving 114 accidents due to fuel contamination with water occurring between January 7, 1980, and September 11, 1981, showed that the probable cause in 85 of those accidents was 'Pilot-in-Command - Inadequate Preflight Preparation and/or Planning.' Since water in fuel accounts for a major share of fuel quality accidents, pilots should make it a practice to include this check beginning with the next preflight inspection."

NTSB Probable Cause

the water contamination of the aircraft's fuel system and the inadequate preflight performed by the pilot. The muddy terrain was a contributing factor.