History of Flight
On June 24, 2008, at approximately 0730 mountain daylight time, a Snow S2C, registration N1661S, impacted terrain while maneuvering to land about 6 miles south of Glenn's Ferry, Idaho. Valley Air Service, Inc. operated the aircraft under 14 CFR Part 137 as an agricultural crop dusting operation. Visual meteorological conditions prevailed; no flight plan was filed. The flight departed Hubler Field Airport in Caldwell, Idaho, around 0600.
The operation involved two aircraft. According to the chief pilot, the accident pilot and he had arrived at the location about an hour prior. Both had completed three fertilizer drops before the accident. During a refueling and reloading on the ground, the chief pilot observed the accident airplane circling overhead at an estimated 500 to 600 feet. He saw the left wing drop, followed by a counterclockwise spin. The airplane completed three 360-degree rotations and struck the ground in a 60-degree nose-low attitude. The chief pilot could not hear the accident airplane due to engine noise from his own aircraft.
Personnel Information
The 21-year-old commercial pilot held certificates for single- and multi-engine land and instrument airplane, as well as a flight instructor certificate with corresponding ratings. He held a second-class medical certificate issued March 27, 2008, with no limitations. Employed by Valley Air Service for about two years, he had approximately 140 hours in the accident aircraft model during the 2008 season and an estimated 2,000 total flight hours. No personal flight records were recovered.
Aircraft Information
The 1964 Snow S2C was originally equipped with a Pratt and Whitney R-985 engine. In 1980, the engine was replaced with a Pratt and Whitney PT6 per CAM 8 authority. In 1997, a PT6-20B (serial number PCE 21794) was installed. The aircraft was operating under 14 CFR Part 137 as an agricultural sprayer.
Meteorological Information
The chief pilot reported clear weather with surface winds from 270 degrees at 15 knots.
Wreckage and Impact Information
The airplane came to rest in an open field. An FAA inspector established flight control continuity. All three propeller blades remained attached; one had a broken tip and midspan bend, another had chordwise scratching and minor S-bending, and the third was buried in dirt with S-bending and scratching. No pre-impact mechanical anomalies were found in the engine.
Medical and Pathological Information
An autopsy performed by the Elmore County Coroner's Office on June 25, 2008, listed the cause of death as blunt force trauma from the aircraft accident. Toxicological analysis by the FAA Forensic Toxicology Research Team was negative for carbon monoxide, cyanide, ethanol, and tested drugs.
Test and Research
A field evaluation by the FAA and Pratt and Whitney found no engine anomalies. Further examination at Pratt and Whitney Canada showed contact signatures consistent with the engine producing power at impact, with no indications of pre-impact mechanical anomalies. Detailed reports are in the public docket.