History of Flight
On June 24, 2013, about 1205 mountain daylight time, a Beech J35 airplane, N8255D, sustained substantial damage after impacting terrain while maneuvering approximately 10 nautical miles north of Helena Regional Airport (HLN), Helena, Montana. The airplane was operated by Vetter Aviation of Helena. The certified private pilot was fatally injured. Visual meteorological conditions prevailed, and the flight was conducted under 14 CFR Part 91 without a flight plan. The local flight departed HLN around 1150.
The operator reported that the pilot departed runway 34 at HLN and flew north to the local practice area, with the intention to return to HLN. A family member indicated two days after the accident that the pilot had planned a trip to the mid-west for the July 4th holidays and was practicing to stay current. Records showed the pilot had flown about 2.5 hours in the previous 30 days.
Witnesses provided statements. One witness, living about 1 nm west of the accident site, heard the engine suddenly change pitch and speed up, then observed a single-engine, low-wing airplane in a nose-down attitude slowly spinning, estimating about five spins before it disappeared. A second witness, about 0.8 nm from the site, heard the props struggling twice and then a impact bang. A third witness, about 8 nm south, observed two airplanes northbound; the larger trailing airplane appeared to make an evasive maneuver to avoid collision, then departed from its original heading. The HLN tower controller watched the accident airplane depart north but saw no other airplane in that vicinity except a Cessna 182 in the traffic pattern. HLN is a non-radar facility with no radar coverage.
Wreckage was located 8 nm north of HLN, impacting relatively flat desert terrain in a steep nose-down, left-wing-low attitude. The airplane came to rest on the west edge of a dry creek bed; no post-crash fire occurred. All flight components were accounted for.
Personnel Information
The pilot, age 51, held a private pilot certificate with a single-engine land rating. According to his logbook, as of May 5, 2013 (the last entry), he had accumulated 177.3 total hours, 99 hours as pilot-in-command, and 69 hours in the accident make and model. He flew 2.5 hours in the preceding 30 days, 2.5 hours in 60 days, and 5.5 hours in 90 days. His most recent biennial flight review was completed on September 7, 2012. He received his most recent FAA third-class medical certificate on February 7, 2013, with limitations requiring corrective lenses for distance and near vision.
Aircraft Information
N8255D, a 1957-model Beech J35 Bonanza, serial number D-5356, was a low-wing, all-metal, single-engine, V-tailed, four-place monoplane with retractable tricycle landing gear. It was white with dark and light blue trim. The airplane was equipped with a fuel-injected, air-cooled, six-cylinder, horizontally-opposed Continental IO-470-C engine (250 horsepower) and a Hartzell 2-bladed, constant-speed propeller. The last annual inspection was dated March 22, 2013, at a total airframe time of 5,904 hours, engine time of 4,686 hours, and 2,020 hours since engine overhaul.
Meteorological Information
At 1153, the HLN weather reporting facility (about 10 nm south of the accident site) reported wind calm, visibility 10 miles, temperature 20°C, dew point 7°C, and altimeter setting 29.65 inches of mercury.
Wreckage and Impact Information
The airplane impacted terrain in a left-wing-down, nose-down attitude on a magnetic heading of 090 degrees; the resting heading was also 090 degrees. After initial impact, the airplane fell aft and came to rest nearly upright, partially on its left side. Ground scars indicated a high-energy vertical impact. Both wings remained attached but sustained impact damage; flaps and ailerons separated from some attach points. Fuel tanks were breached; no fuel was recovered. The fuel selector was in the left main tank position, and the handle rotated freely 180 degrees. Both ruddervators remained attached. The aft fuselage was bent, twisted, and wrinkled. Control cable continuity was confirmed from wings and empennage to the forward cabin area. The cabin and cockpit were deformed down and aft. All cockpit instruments were destroyed; propeller, throttle, and mixture controls were in full forward position. Nose and main landing gear were not at the site; post-recovery examination showed all three in retracted position. No airframe anomalies were found that would have precluded normal operation.
Medical and Pathological Information
An autopsy performed on June 24, 2013, at the Montana State Forensic Science Division determined the cause of death as blunt force injuries. A forensic toxicological examination by the FAA Civil Aeromedical Institute showed no ethanol detected; amlodipine (a blood pressure medication) and ranitidine (an indigestion medication) were detected. Tests for carbon monoxide and cyanide were not performed.
Tests and Research
On June 26, 2013, the engine was recovered to a secured hangar at HLN for inspection by a Continental Motors field technician, supervised by the NTSB and FAA. The examination revealed no abnormalities that would have prevented normal operation or power production.