Safford

The aircraft was destroyed when it impacted terrain in the Superstition Mountains near Apache Junction, Arizona. The commercial pilot and the five passengers were fatally injured. The airplane was registered to Ponderosa Aviation, Inc. (PAI) and operated by PAI under the provisions of 14 Code of Federal Regulations (CFR) Part 91 as a personal flight. Night visual meteorological conditions (VMC) prevailed, and no flight plan was filed. The airplane had departed Falcon Field (FFZ), Mesa, Arizona, about 1825 and was destined for Safford Regional Airport (SAD), Safford, Arizona. PAI’s director of maintenance (DOM) and the director of operations (DO), who were co owners of PAI along with the president, conducted a personal flight from SAD to FFZ. The DO flew the leg from SAD to FFZ under visual flight rules (VFR) in night VMC. After arriving at FFZ and in preparation for the flight back to SAD, the DOM moved to the left front seat to act as the pilot flying. The airplane departed FFZ about 12 minutes after it arrived. According to a witness, engine start and taxi-out appeared normal. Review of the recorded communications between the pilot and the FFZ tower air traffic controllers revealed that when the pilot requested taxi clearance, he advised the ground controller that he was planning an "eastbound departure." The flight was cleared for takeoff on runway 4R, and the pilot was instructed to maintain runway heading until advised, due to an inbound aircraft. About 90 seconds later, when the airplane was about 1.1 miles from the departure end of the runway, the tower local controller issued a "right turn approved" advisory to the flight, which the pilot acknowledged. Radar data revealed that the airplane flew the runway heading for about 1.5 miles then began a right turn toward SAD and climbed through an altitude of about 2,600 feet mean sea level (msl). About 1828, after it momentarily climbed to an altitude of 4,700 feet, the airplane descended to an altitude of 4,500 feet, where it remained and tracked in an essentially straight line until it impacted the mountain. The last radar return was received at 1830:56 and was approximately coincident with the impact location. The impact location was near the top of a steep mountain that projected to over 5,000 feet msl. Witnesses reported seeing a fireball, and law enforcement helicopters were dispatched.

The airplane impacted a road and scrub brush during a forced landing, which was preceded by a total loss of engine power. According to the pilot, he heard a loud "thunk" during takeoff climb and noted a loss of engine power. He manipulated the power lever from the full forward position to the full aft position ("stop-to-stop") and noted he had no power. Post-accident examination of the Pratt & Whitney Canada PT6A -114A engine revealed that the compressor turbine (CT) vane's outer rim liberated a section of metal that damaged the turbine blades downstream. The area of liberated material from the CT vane outer rim was examined by the manufacturer's metallurgists. The fracture surface of the outer rim showed evidence of fatigue with signs of oxidation in some areas indicating the crack had been in existence for some time. The liberated material impact damaged the CT blades and resulted in a loss of power. Review of the operator's records revealed that the engine was approved for an extension beyond the normally recommended 3,600-hour overhaul period, to 5,100 hours. The engine had accumulated 4,461.3 hours at the time of the accident. In addition, the turbine section (hot section) had a recommended overhaul period of 1,800 hours; however, the operator instead elected to utilize an engine trend monitoring program in accordance with a manufacturer issued service bulletin. Many errors were noted with the operator's manually recorded data utilized for the trend monitoring. However, it is not likely that the engine trend data, even had it been correctly recorded and monitored, would have depicted the fatigue cracking in the CT vane outer rim. As a result, the manufacturer issued a service information letter (SIL) PT6A116 in January 27, 2003 (following a similar investigation), which reminded operators to conduct borescope inspections of the CT vane during routine fuel nozzle maintenance, as the manufacturer's maintenance manual recommended. Review of the maintenance record entries for the accident engine revealed no evidence that a borescope inspection had been conducted in conjunction with the fuel nozzle checks.

During the night cross country flight at FL250, the pilot elected to leave the cockpit area and move to the rear of the aircraft to attend to physiological needs. Although oxygen was available in the cockpit, supplemental oxygen was not available in the rear. The aircraft was operated with a known pressurization system deficiency which limited the airplane to flight to 17,000 feet msl while maintaining a cabin altitude of 10,000 feet. After 2 hours and 10 minutes, atc declared the flight to be 'no radio'. At 3 hours and 57 minutes after departure, the airplane was plotted on radar in a descending left turn to ground impact. Fuel starvation resulted in power loss to the left engine. Propeller signatures indicated power on the right propeller at impact. The pilot's body was found in the aft cabin area on the aft cabin bulkhead.

The crew departed Tucson Airport in the early morning on a firefighting mission in the region of Safford. While flying at low height over the forest in fire, the airplane struck trees and crashed in a mountain slope. The aircraft was totally destroyed and both occupants were killed.

The crew was engaged in a local fire control mission. En route, the twin engine airplane crashed in unknown circumstances in the region of Safford, killing both occupants.

Crashed in unknown circumstances in a mountainous area located about 13 miles north of Safford. The pilot Wilfred P. Champlain, sole on board, was killed.