Accident Overview
On September 25, 2016, at about 1600 Alaska daylight time, a Helio Courier H-295 airplane, registration N68857, sustained substantial damage during a takeoff from a remote, unimproved airstrip located approximately 35 miles southwest of Delta Junction, Alaska. The certificated airline transport pilot, the only occupant, was not injured. The airplane was registered to Bursiel Equipment, Inc., Fairbanks, Alaska, and operated by Wright Air Service, Fairbanks, as a visual flight rules (VFR) on-demand commercial flight under 14 CFR Part 135. Visual meteorological conditions prevailed at the time, and a VFR flight plan had been filed. The flight originated from Fairbanks International Airport about 1500.
Pilot Account
During a telephone interview on September 26, the pilot stated that the airplane landed at an 800-foot gravel airstrip near the East Fork of the Little Delta River about 1540 to collect moose meat for a customer. The meat weighed 625 pounds and was loaded into the airplane. The pilot reported on the NTSB Form 6120.1 that approximately 1-2 inches of wet snow had accumulated on the airstrip, with winds from the north/northeast at an estimated 7 knots. Visibility was reported as 5 statute miles with light snow. The pilot calculated the takeoff weight at 3400 pounds with a mid center of gravity.
After conducting a pre-takeoff contamination check, the pilot set flaps to 30 degrees, trim for takeoff, and completed the before takeoff checklist. He positioned the airplane for a departure to the north, locked the tail wheel, confirmed flaps and trim, and selected a go/no-go point about 400 feet down the airstrip. The initial takeoff roll appeared normal through the decision point, but with about one-third of the airstrip remaining, the pilot realized the airplane would not become airborne at the designated point and that he could not stop in the remaining distance due to snow. He opted to continue the takeoff through low brush at the end of the airstrip to gain more airspeed. The airplane became airborne, settled back, then became airborne again. The main landing gear struck brush on a small embankment, and the airplane began settling. The pilot observed a clear area leading to a creek bed, reduced power to idle, and held full aft elevator. The airplane touched down in a three-point attitude and came to rest in the creek bed with a left wing low. After exiting, the pilot noted calm wind and stopped snowfall.
Damage
The airplane sustained substantial damage to the vertical stabilizer.
Mechanical Condition
According to the pilot, there were no preimpact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.
Meteorological Conditions
The closest weather reporting facility, Allen Army Airfield at Fort Greely, Alaska, about 35 miles northeast of the accident site, reported at 1559: wind calm; visibility 10 statute miles; scattered clouds at 1,300 feet, broken clouds at 3,200 feet; temperature 37°F; dew point 36°F; altimeter 29.93 inHg.
Aircraft Performance Considerations
The Helio H-295 Airplane Flight Manual includes performance charts for takeoff ground run and takeoff distance to clear a 50-foot obstacle. The ground run chart includes correction factors for wet grass and soft turf but not for wet snow. The obstacle clearance chart does not include correction factors for the pilot to use.
Operational Guidance
FAA publication FAA-H-8083-3A Airplane Flying Handbook (2004) discusses takeoffs from soft fields, noting that soft surfaces or long, wet grass can reduce acceleration, potentially preventing attainment of adequate takeoff speed with normal techniques. The Civil Aviation Authority of New Zealand's Takeoff and Landing Performance (2011) states that grass, soft ground, or snow increase rolling resistance, lengthening takeoff ground run compared to paved runways.