History of Flight
On April 10, 2015, about 1225 mountain daylight time, a Cessna Centurion T210M, registration N732YQ, collided with trees shortly after departing from Upper Loon Creek USFS Airport, located in the Salmon-Challis National Forest near Challis, Idaho. The pilot, who was the registered owner, was operating the airplane under 14 CFR Part 91. The private pilot and three passengers sustained fatal injuries; the airplane sustained substantial damage. The personal cross-country flight originated from Upper Loon Creek with a planned destination of Driggs-Reed Memorial Airport, Driggs, Idaho. Visual meteorological conditions prevailed, and no flight plan had been filed.
The pilot had a solar energy system installed at his residence in the Driggs area and wanted the same solar company, Creative Energies, to assess the feasibility of a similar installation at his private residence at Diamond D Ranch, where he was a partial owner. The pilot had been staying in Driggs for several days and planned to take a few Creative Energies employees to the ranch to evaluate solar installation possibilities. Earlier in the week, he notified the ranch manager of his intention to fly into Upper Loon Creek, located about two miles downstream from the ranch on a northeasterly heading. During winter, the ranch is only practically accessible by air. The pilot and three passengers departed Driggs with full fuel in the wing tanks. After completing the approximately 170-nautical-mile flight, they landed at Upper Loon Creek. The solar employees performed their assessment, and the group left the ranch. The pilot told ranch personnel he wanted to depart before the wind picked up. No witnesses observed the accident, and no one at the ranch heard the airplane depart.
Personnel Information
The pilot, age 70, held a private pilot certificate with ratings for single-engine land, multiengine land, and instrument airplane. His third-class medical certificate was issued on January 8, 2015, with a limitation requiring corrective lenses for distant vision and glasses for near vision. He also held a type certificate for a Lear Jet. His personal flight records were not recovered. On his last medical application, he reported 9,051 total flight hours, with 42 hours in the preceding six months. His spouse stated he frequently flew into Upper Loon Creek; this was his first trip to the ranch since fall 2014. She recalled he would normally depart in a direction away from the ranch (northeast) and make a straight-out departure until reaching a ridge, where he would begin circling to gain altitude.
Aircraft Information
The Cessna T210M, serial number 21061884, was manufactured in 1977. Airplane logbooks were not provided to the NTSB. The last annual inspection was completed on December 8, 2014, at a total airframe and engine tachometer time of 3,669.4 hours; time since major overhaul was 1,341.4 hours. The last maintenance, recorded in January 2015, consisted of servicing the left brake and oxygen hose.
Fuel records indicate the airplane was last fueled at Driggs on April 4, 2015, with 50.4 gallons added. The line manager reported the airplane was not flown between that fueling and the flight to Upper Loon Creek. The JPI unit showed 14 gallons had been used since fueling, indicating approximately 70 gallons on board at accident takeoff.
Weight and balance computations estimated a gross weight of 3,551 pounds, based on 70 gallons of fuel, pilot and passenger weight of 745 pounds (from Custer County records), baggage weight of 50 pounds, and an empty weight of 2,322 pounds. Performance data for a dry grass runway at the accident altitude (5,500 ft msl) with a temperature of 10°C and a gross weight of 3,500 pounds indicated the following distances to clear a 50-ft obstacle: no wind: 2,231 ft; 2.5-kt tailwind: 2,454 ft; 5-kt tailwind: 2,677 ft; 7.5-kt tailwind: 2,900 ft; 10-kt tailwind: 3,123 ft. Assuming a 5-kt tailwind as reported by the ranch manager, the calculated distance was 2,677 ft. The actual distance from the takeoff start point (derived from GPS data) to the first impacted tree (approximately 50 ft high) was about 2,625 ft.
Meteorological Information
Just before the accident, the pilot mentioned to a ranch caretaker that he wanted to depart before the wind picked up. The caretaker estimated wind from the south at 4–5 kts at the ranch, with a temperature of about 55°F (13°C). Weather stations nearby reported: at Little Creek (11 nm northwest, about 25 minutes after the accident), temperature 13°C, wind from 352° at 2 kts gusting to 5 kts; at Bonanza (14 nm southeast), temperature 10°C, wind from 180° at 7 kts gusting to 15 kts. Local pilots noted downdrafts at drainage confluences near the runway and rapid spring weather changes. Using a temperature of 10°C and an airport elevation of 5,500 ft msl, density altitude was approximately 6,046 ft msl.
Wreckage and Impact Information
The accident site was partially submerged in a shallow creek paralleling the runway; the fuselage and most wing skin were consumed by fire. The airplane came to rest inverted on level terrain, with a debris path oriented on a 080° magnetic heading. The main wreckage was about 600 ft from a fence at the end of runway 04 on a heading of 060°. The first identified impact point comprised broken tree limbs about 170 ft northeast of the fence center and 430 ft southwest of the main wreckage. The first tree impacted had a fork at about the 50-ft level with fresh cuts. Numerous broken branches led to the main wreckage. The nose wheel was about 100 ft from the first tree; the left main landing gear tire was found farthest from the debris field, on the southwest bank. The outboard half of the left horizontal stabilizer was found in the river.
Medical and Pathological Information
An autopsy on the pilot showed no evidence of soot deposition in the trachea. Toxicological tests were positive for Atorvastatin and Diltiazem; ethanol was negative.
Tests and Research
Examination of the airframe and engine revealed no evidence of mechanical malfunction or failure that would have precluded normal operation. The engine was test-run and produced rated horsepower normally. The propeller blades were attached and showed no evidence of chordwise scratching or leading-edge damage consistent with power at impact. GPS data showed the accident flight lasted about two minutes, with a ground speed increasing from 6 kts to 80 kts. The airplane reached 5,567 ft on the penultimate data point and descended 96 ft on the last. Comparison with nine prior takeoffs from runway 04 showed the accident flight path was slightly left of the typical track. The JPI engine monitor recorded engine parameters; the last reliable data point indicated 2,700 rpm with symmetric cylinder temperatures.