Summary
On Sunday, 6 November 1966, the pilot of a Jodel D 11, registration HB-SOD, departed Prangins aerodrome at approximately 15:00 local time for a pleasure flight over the Nyon–Lausanne–Vallée de Joux region. He was accompanied by his wife, who frequently flew with him. Around 15:15, the aircraft arrived over the Mollendruz pasture in the Vaud Jura, where it performed several low-altitude circles in turbulent air. During these maneuvers, the aircraft struck the ground and then hit a telephone pole. The pilot was killed instantly; his wife sustained serious injuries. The aircraft was completely destroyed. The investigation found no technical defects.
Investigation
The preliminary investigation was concluded on 28 March 1967 and the final report was issued on 26 May 1967. The investigating authority was the Federal Commission of Inquiry into Aircraft Accidents.
Aircraft Information
- Type: Jodel D 11
- Registration: HB-SOD
- Engine: Continental C85-8F
- Propeller: McCauley 1B90 metal
- Year of manufacture: 1957
- Fabricator: Pfäffikon/ZH
- Total time: 652 hours, 1,455 landings at time of accident
- Weight and balance: Within limits (532 kg total, CG at +0.41 m)
- Last inspection: 13 October 1966
- No prior accident history
Pilot and Passenger
- Pilot: Born 1923, held a private pilot license issued 30 June 1964, valid until 10 November 1967. Total flying experience 190:09 hours (604 landings), with 136:33 hours (298 landings) on the accident aircraft since purchase on 13 March 1965. Last medical check on 10 November 1965 showed no abnormalities. Toxicology tests negative for alcohol. No prior accidents or infractions.
- Passenger: Born 1928, wife of pilot, no aeronautical qualifications.
Accident Sequence
After lunch, the pilot and his wife drove their son to Geneva. On return, the pilot proposed a flight, which was common. He refueled at Prangins (estimated 50 liters of gasoline) and departed at 15:00. At about 15:15, several witnesses saw the aircraft arrive from the south over the Mollendruz pasture at an altitude below 50 m (estimated 15–20 m). The wind was not strong, but turbulence was present. Before reaching the forest edge, the aircraft was jolted by a gust. Over the pasture, the aircraft performed two tight left-hand circles (diameter ~200 m) with bank angles varying from 25° to 85°. Turns near the mountain were steep due to proximity to fir trees.
After a final left turn over the Mollendruz chalet, the aircraft headed northwest, passing a few meters above a pasture wall. Just after the wall, instead of climbing to clear a telephone line, the aircraft pitched down and struck the ground 4 m before a telephone pole with a brace. The left wing, already contacting the ground with the landing gear, broke off as it struck the pole about 30 cm above the ground. The engine impacted the earth near the pole. The occupants were thrown forward, tearing out the instrument panel and fuel tank, and came to rest 20 m ahead of the impact point. The pilot died instantly; his wife, unconscious, was taken to the hospital.
Meteorological Conditions
Foehn conditions north of the Alps. Cloud cover: 6/8 with 3/8 Altocumulus at 4,500 m and 6/8 Cirrus. Below 900–1,000 m: heavy haze, horizontal visibility ~5 km; above: clear, visibility 50–100 km. Winds at surface: weak and variable below 1,000 m; at 1,500 m: 160/20 kt, gusts 30–35 kt; at 2,000 m: 180/35 kt; at 3,000 m: 200/45 kt. Turbulence: none below 1,000 m; moderate above, strong near slopes. Pressure: 3 mb below standard (QNH 1010 mb). Sun: 15° elevation, 225° azimuth (SW).
A witness pilot flying near Ste-Croix at 1,800–1,900 m reported no turbulence but noted strong wind from the south, with moderate turbulence and low ground altitude.
Damage
- Pilot: Killed instantly.
- Passenger: Serious bodily injuries, hospitalized for about two months.
- Aircraft: 100% destroyed.
- Ground damage: Telephone pole severed at base; cost ~150 CHF.
Conclusions
The accident occurred because the pilot lost control of the aircraft during maneuvers at very low altitude over mountainous terrain scattered with obstacles, in turbulent conditions.