CHI94DTK02

The pilot reported a loss of engine power immediately after takeoff. He made a forced landing and departed the end of the runway. The airplane was destroyed in the ensuing fire. Investigation revealed broken vanes in the engine driven fuel pump and a sheared fuel pump shaft.

On June 21, 1994, about 1900 central daylight time an Ayres S2R airplane, N3102E, operated by MJ Aviation, Inc. of Letcher, South Dakota was destroyed during a forced landing two miles east of Letcher. The commercial pilot sustained no injuries. Visual meteorological conditions prevailed for the aerial application flight conducted under CFR 14 Part 137. The flight originated at the operators private airstrip approximately 1900 to provide aerial application of herbicides to fields in the area where the accident occurred. No flight plan was filed.

The pilot reported that prior to takeoff, the aircraft was serviced with an additional 35 gallons of 100 low lead aviation fuel for a total of 60 gallons of fuel on board. A total of 230 gallons of herbicide mix was loaded in the hopper. The aircraft was taxied to the north end of the sod strip and an abbreviated run up was performed to bring up the cylinder head temperature. Upon completion of the checklist, the throttle was advanced to start the takeoff, departing to the south.

The takeoff was reported to be normal until the airplane reached an altitude of about 20 feet AGL. At that point, the engine lost power. The power loss was smooth and unaccompanied by any unusual noises or vibration. The throttle was advanced with no response. The pilot had to abort the takeoff and a landing was attempted on the remaining runway.

The airplane touched down 300 to 500 feet before the end of the runway. With insufficient stopping distance, it hit the roadway embankment which is perpendicular to the runway. The airplane continued across the road, through a ditch, and stopped in a field, turning 90 degrees to the right to a heading of 270 degrees.

The right wing fuel tank ruptured and the engine displaced to the right of the airplane's longitudinal axis. Fire immediately ensued and the pilot exited through the left-side door. The aircraft's center section burned until extinguished by the local fire department, approximately 10 minutes after ground impact. The aircraft was destroyed beyond economical repair.

Postaccident examination revealed the left main landing gear was separated from the airplane. There was no fuel remaining. Flight and engine instruments, and electric switching panels were destroyed. The tail section, empennage, and wing tips were not burned. One propeller blade was bent aft at the outer one-third of the blade. Flight controls were intact and there was continuity of all controls. Engine and power quadrant controls were intact and there was continuity between them.

The engine was installed on the aircraft in 1993. Engine tear down revealed that the main fuel pump, engine driven fuel pump drive shaft was sheared. The fuel pump was disassembled, all carbon vanes were broken up and the pump internal workings would not rotate. The main fuel filter was clean. The blower would not turn and the blower main shaft was not sheared.