Event Details
The pilot and owner of a single-engine agricultural airplane reported that he adjusted the gas turbine rotation speed (Ng) by "one click" prior to departure, increasing engine power from 96 percent to 100 percent. Shortly after takeoff, at approximately 150 feet above ground level, the pilot observed that the Ng speed remained at 96 percent. He initiated a turn back toward the airport. During the turn, the engine lost power, and the pilot was unable to maintain altitude. He performed a forced landing onto a dirt road, where the airplane struck a stop sign, then crossed a highway before coming to rest in an open field. The pilot noted that the engine still produced enough power to taxi the airplane out of the field and back onto the highway.
Engine Examination
External examination revealed a 5-inch-wide hole in the engine's compressor housing. The engine was disassembled into two sections: the power section module and the gas generator module. Damage to the power section included torn and nicked compressor turbine blades on the leading edge, extensive foreign object damage (FOD) to the hot section stator vanes, and a bent, buckled, and torn power turbine shroud with several bolts sheared out of their holes. The containment ring was split in half, and the power turbine stator vanes were torn and deformed. The power turbine wheel had 10 sheared blades at or near the root, with several other blades broken in half. The chip detector was filled with large metal chips, and the oil filter contained a small amount of fine metallic particles. Examination of the gas generator module revealed no anomalies in the compressor bleed valve, fuel manifolds, compressor turbine stator assembly, accessory gear box assembly, impeller, compressor inlet case, compressor rotor in the gas generator case, or compressor turbine blades.
Maintenance Records
A review of maintenance records showed that the last 100-hour inspection was performed on April 27, 2007, at a Hobbs time of 5,892.9 hours. However, there was no record of the engine's last overhaul, no record of present engine total time or time since overhaul, and no record of engine removal from the aircraft.
Conclusion
The reason for the loss of engine power could not be determined.