DEN99LA131

The pilot departed the airport and leveled off at a cruising altitude of 14,500 feet msl. He leaned the mixture and set a cruise power setting of 24 inches of manifold pressure and 2400 rpm. Shortly thereafter, the manifold pressure dropped to 22 inches. He applied power, and the manifold pressure was briefly restored, then dropped again. He found an open field in which to make an emergency landing. Prior to touching down, the left wing impacted a tree, and the aircraft nosed over upon impact with the ground. Following the accident, a teardown inspection was performed on the turbocharger. Evidence of rotational scoring was found on the turbine components. The rotation of the thrust bearing was allowed by the displacement of the anti-rotation pins below the surface of the center housing. Rotational score marks on the back side of the turbine wheel provided evidence that the turbine wheel had contacted the turbine shroud. According to the aircraft maintenance records, the last major overhaul of the turbocharger was accomplished in 1987

On July 30, 1999, approximately 0845 mountain daylight time, a Cessna T210F, N6125R, registered to and operated by the pilot, was substantially damaged when it collided with terrain during a forced landing following a partial loss of engine power 2 miles northwest of Fairplay, Colorado. The private pilot, the sole occupant aboard, received serious injuries. The flight was being conducted under Title 14 CFR Part 91, and no flight plan had been filed. The flight originated from Centennial Airport, Englewood, Colorado, at 0800, and was en route to Aspen, Colorado. Visual meteorological conditions prevailed.

According to the pilot, prior to departure from Englewood, he requested that the aircraft be "topped off" with fuel. A fuel receipt provided by Signature Flight Support indicated that 15 gallons of fuel were added to N6125R. After takeoff, he climbed to a cruising altitude of 14,500 feet mean sea level (msl). He leveled off at that altitude and leaned the mixture. He set a cruise power setting of 24 inches of manifold pressure and 2400 rpm. As he was approaching the vicinity of Hoosier Pass, he noticed that the manifold pressure had dropped to 22 inches. He applied power, and the manifold pressure was temporarily restored to 24 inches.

He stated that "then suddenly [there was a] continuous decline in power." He turned toward the southeast in an attempt to land at the old airport in Fairplay, which is now closed. He turned the fuel pump on and switched to the left fuel tank, but was unable to restore power to the engine. Realizing that he did not have sufficient altitude to glide to the old airport, he observed an open field on which to make an emergency landing. He added 20 degrees of flaps, and decided to make a gear up landing. Prior to touching down, the left wing impacted a tree and partially separated from the aircraft. Upon impact with the ground, the aircraft nosed over.

On August 5, 1999, the aircraft was examined at the facilities of Beegles Aircraft in Greeley, Colorado. In attendance were investigators with Teledyne Continental Motors and the Cessna Aircraft Company. No discrepancies or abnormalities were found with either the airframe or the engine.

On August 17, 1999, a teardown inspection was performed on the TE06 model turbocharger (part number 406610-5, serial number FH0107) and the associated controls with the assistance of an engineering representative with AlliedSignal Aerospace, the turbocharger manufacturer. Evidence of rotational scoring was found on the turbine components. The rotation of the thrust bearing was allowed by the displacement of the anti-rotation pins below the surface of the center housing. Damage to the thrust bearing was observed. Rotational score marks on the back side of the turbine wheel provided evidence that the turbine wheel had contacted the turbine shroud. In addition, there was a rotational deposit of oil on the transition and outlet surfaces of the compressor impeller shroud. There was no evidence found that would indicate that the turbocharger was rotating at the time of the accident. The wastegate and absolute/rate controller were functionally tested. Both were found to be operational.

During the teardown inspection, a non standard data plate was found on the turbocharger, providing documentation that the turbocharger had been rebuilt subsequent to its original manufacture. According to the aircraft maintenance records, the last major overhaul of the turbocharger was accomplished on February 5, 1987, at Chuck's Aircraft, Inc., San Carlos, California.