1965 Piper PA-22-108 Colt Accident at Albulapass (D-EHRO)

Accident Overview and Investigation Approval The Swiss Federal Aircraft Accident Investigation Commission approved its final report on 22 April 1965, with three redacted changes, concerning the accident of the Piper PA-22-108 “Colt” D-EHRO on 8 March 1965 at Albulapass (Bergün), Graubünden. The report was circulated on 27 May 1965. ## Flight Details and Occupants The aircraft was on a flight from Stuttgart to Samedan. The pilot, born in 1942 and a German national, held a private pilot licence issued on 15 May 1964 by the Regierungspräsidium Nordbaden in Karlsruhe, valid until 28 January 1966. His total experience was about 63 flight hours and 194 landings, including about 11 hours and 24 landings on the accident type, with no mountain-flying experience. The passenger, born in 1943 and a German national, had no flying experience or licences. ## Aircraft and Technical Findings The aircraft was a privately owned Piper PA-22-108 “Colt” with a Lycoming O-235 GIB engine and a fixed two-blade metal propeller, Sensenich M76AM-2. It was built in 1962, serial number 9336, and manufactured by Piper Aircraft Corp., Lock Haven, Pa., USA. The maximum takeoff weight was 750 kg, and the accident weight was about 620 kg. The centre of gravity remained within prescribed limits throughout the flight. The investigation found no technical defects in the aircraft. ## Weather and Terrain On the day of the accident, the weather in Switzerland was under the influence of a strong high-pressure system. In the accident area, there was 1/8 cumulus cloud at 2,500 m, visibility over 50 km, wind at the pass of 10–15 knots from WSW, temperature −10 °C, and pressure 1013 mb QNH. The accident occurred on the pass height of Albulapass, in a terrain cut immediately before the pass, near a high-voltage line, about 80 m before the pass-height sign and about 120 m from the hospice. ## Sequence of Events The pilot took off from Baden-Oos at 10:54 MEZ on 8 March 1965 with one passenger for Samedan, his first Alpine or foreign flight. He landed at Stuttgart at 11:36, obtained flight information, filed a flight plan, and completed customs formalities. With permission for an intermediate landing at a military base near Leipheim, he took off from Stuttgart at 12:26. He landed at Leipheim at 13:15 and took off at 14:57. He then made an unplanned intermediate landing at Bad Ragaz to seek further information and advice for the flight into the Engadin, but found no one on the field and took off again. The times at Bad Ragaz were not recorded. Flying over Landquart, Klosters, and Davos, the pilot reached Filisur and the north slope of Albulapass, which he then attempted to cross in a direct flight. He knew the elevation of the pass and was convinced that his aircraft could overcome the height difference without difficulty and without climbing turns. However, he could not state his starting altitude in the Filisur area. Shortly after Crap Alv, at the entrance to the saddle, he realized that he probably would not be able to cross the pass in a direct flight, but the required ground clearance for a turn-around was no longer available. With little hope of getting through, he steered the aircraft at full throttle toward the lowest terrain point. The ground continued to rise faster than the aircraft, and shortly before the pass height, at the exit of the saddle, ground contact became unavoidable. The pilot pulled the elevator control and set the aircraft down in open, slightly rising terrain, where it immediately overturned in deep snow. ## Injuries and Damage The pilot sustained minor abrasions to his hands and head. The passenger, who also had minor head injuries (cuts and lacerations to the forehead and right ear), was treated medically in Samedan after rescue. The aircraft, with a new value of about SFr. 25,000, sustained damage to the nose wheel, engine mount and fairing, and the cabin front windshield. The accident-related repair costs were estimated at about SFr. 3,000. The aircraft was dismantled and recovered with the help of a snow-caterpillar vehicle by members of the Swiss Air Rescue Service. ## Findings and Discussion Cockpit findings at the accident site showed the throttle at full, the mixture control on “Rich,” the carburetor preheat off, the altimeter set to 1028 mb, and the stabilizer slightly trimmed tail-heavy. The investigation concluded that the forced landing was unavoidable because the pilot did not maintain a safe option for retreat when the planned flight became infeasible. The immediate cause was that the pilot, approaching the pass height too closely, missed the moment when a turn-around and gaining the missing altitude in more open space would still have been possible. His failure to compare his altitude more attentively with the topographical course of the valley, and thus to recognize the hopeless situation in time, could be partly attributed to his lack of mountain-flying experience.