NTSB Factual Report

On November 3, 2006, at 0720 central standard time, a Piper PA-46-310P, N460TM, collided with the terrain during an off airport forced landing in Chester, Illinois, following a loss of engine power. The pilot was not injured. The airplane sustained substantial damage. The 14 Code of Federal Regulations Part 91 personal flight was operating in visual meteorological conditions and an instrument flight rules flight plan was filed. The flight originated from Cape Girardeau, Missouri, at 0645, with an intended destination of the DuPage Airport, West Chicago, Illinois.

The pilot reported that after reaching a cruising altitude of 9,000 feet the engine "missed" and the oil pressure, oil temperature, and manifold pressure began to drop. He stated he turned on the low pressure fuel boost pump to try and increase the manifold pressure.

The pilot stated he contacted air traffic control and requested a turn to the nearest airport. He turned toward the airport and maintained a 500 to 800 foot per minute descent. Once he realized he was not going to make it to the airport he chose a field in which to land. He stated he cleared the trees, which surrounded the field, and applied flaps to slow the airplane. The field was muddy so the pilot used the emergency gear extension to lower the landing gear so the airplane would not slide into the trees. The airplane touched down and slid approximately 25 feet prior to coming to rest.

The left wing was pulled loose from the fuselage, the left and right flaps sustained impact damage, and the landing gear was destroyed.

The engine was torn down and inspected. This inspection revealed that both halves of the crankcase contained holes in line with the number four cylinder. The crankshaft and counterweight assembly showed signs of thermal and mechanical damage at the number four and five connecting rod journals. The number four and five connecting rod journals also showed signs of thermal and mechanical damage. The oil transfer passages were not blocked and the oil transfer collar was intact. The number four connecting rod exhibited thermal and mechanical damage and was fractured through the base of the I-beam. Only fragments of the number four connecting rod cap, rod bolts, nuts, and bearing were found. The number five connecting rod assembly also sustained thermal damage.

A hole was noted in the turbine wheel shroud on the hot section of the right turbocharger. There was no data plate, serial number, or model number present on the turbocharger. The turbocharger did contain the part number 466304-0003. The oil inlet and outlet fittings were intact and showed no signs of oil leakage. This turbocharger was sent to Kelly Aerospace for teardown and inspection. The inspection revealed the turbine wheel shroud had fragmented as a result of a fatigue failure. The back surface of the shaft and wheel assembly contained contact signatures from the shroud.

The airplane had been operated in Australia under the registration of VH-BTZ. Maintenance records showed that both the left and right turbochargers were installed on June 21, 1988, at an aircraft total time of 1,527.9 hours and that the mandatory life limit on the turbochargers was 2,000 hours. The total airframe time at the time of the accident was about 2,830 hours. The data plate on the left turbocharger matched the information in the maintenance records. Without a serial number on the right turbocharger, it could not be verified that this was the same one that was installed on June 21, 1998. However, the maintenance logs provided did not contain a record of the turbocharger having been replaced after that date.

NTSB Probable Cause

The fatigue failure of the turbocharger shroud which resulted in oil starvation to the engine. A factor was the muddy field.