ERA16LA059

The commercial pilot of the single-engine turboprop airplane reported that he was preparing to release skydivers when he noticed that the engine torque indication was in the red arc. Specifically, the gauge was indicating a torque of 70 pounds per square inch (psi) when it should have been indicating about 25 psi; the maximum allowed torque indication was 64.5 psi. The skydivers jumped uneventfully. As the pilot was returning to the airport, the torque gauge was indicating 80 psi while the engine was at idle. At that time, the pilot decided to perform a precautionary engine shutdown and land with no engine power. During the landing, the airplane was fast and touched down about halfway down the 3,402-ft-long asphalt runway. The pilot applied heavy braking, but the airplane traveled about 1,000 ft beyond the departure end of the runway before coming to rest upright in a field with a collapsed left main landing gear. Two examinations of the engine did not reveal any preimpact anomalies or evidence of overtorque. A test of the torque-indicating transducer and gauge also did not reveal any anomalies. The examinations did reveal that an automotive-type wiring bundle was used to wire the torque transducer to the airplane's electrical system. Although it is possible that the wiring bundle could have caused an intermittent faulty torque indication, subsequent testing was unable to duplicate the problem. The airplane was manufactured about 10 years before the accident, and the torque meter manufacturer upgraded the wiring connectors about 4 years before the accident.

On December 3, 2015, about 1120 eastern standard time, a Pacific Aerospace 750XL, N216PK, registered to and operated by Paraclete Aviation LLC., was substantially damaged during a precautionary landing at P K Airpark (5W4), Raeford, North Carolina. The commercial pilot was not injured. The commercial skydiving flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed for the local flight, which departed 5W4 about 1100.The pilot reported that the airplane was at 13,000 feet mean sea level (msl) as he was preparing to release the skydivers. He then noticed that the torque gauge was in the red arc and indicated a torque of 70 psi when it should have indicated about 25 psi; the maximum allowed torque indication was 64.5 psi. The pilot notified the skydivers of the anomaly and told them to jump, which they did uneventfully. As the pilot was approaching 5W4 for a normal landing, the airplane was at 9,000 feet msl and the torque gauge indicated 80 psi while the engine was at idle. At that time he decided to perform a precautionary engine shutdown to prevent catastrophic engine failure. The pilot further stated that during the landing with no engine power, the airplane was fast and touched down about halfway down runway 4, a 3,402-foot-long asphalt runway. The pilot applied heavy braking, but the airplane traveled about 1,000 feet beyond the departure end of the runway, before coming to rest upright in a field with a collapsed left main landing gear. Examination of the wreckage by a Federal Aviation Administration (FAA) inspector revealed substantial damage to both wings. The airplane was manufactured in 2005 and equipped with a Pratt and Whitney PT6A-34 turboprop engine. Subsequent examination of the engine by the FAA inspector and a representative from the engine manufacturer did not reveal any preimpact anomalies or evidence of overtorque. A "dead weight" test was then performed, to simulate pressure from the engine and test the torque indicating transducer and gauge. The test was performed satisfactorily and no anomalies were noted with the transducer or gauge. The operator subsequently performed a second examination of the engine due to a propeller strike during the precautionary landing. That examination also did not reveal any evidence of overtorque or anything that would have caused a faulty torque indication. The examinations did note that an automotive-type wiring bundle was used to wire the torque transducer to the airplane's electrical system. Although the results of the "dead weight" were satisfactory, the test may not have been able to detect an intermittent wiring anomaly. Additionally, the airplane manufacturer reported that the torque meter manufacturer upgraded the wiring about 4 years prior to the accident, from spade connectors to overlap connectors. Pope Army Airfield (POB), Fayetteville, North Carolina, was located about 12 milesnortheast of the accident site. The recorded weather at POB, at 1118, included wind from 360 degrees at 10 knots, clear sky, and visibility 10 miles.