Summary
On 23 May 1978 at 1058 local time, a Piper Cherokee PA28-140, registration LN-HHM, took off from Karmøy bound for Fritzøe (Larvik). The pilot was the sole occupant. No flight plan was filed; the flight was to be conducted under VFR and was estimated to take about two hours. The last radio contact with air traffic services occurred at 1105 when the pilot reported passing Vestre Bokn at 1500 feet. After the aircraft did not arrive at Fritzøe during the day, a friend contacted Fornebu control tower around 2300 to inquire. Following checks revealing the aircraft had departed Karmøy without a flight plan, the friend reported the aircraft missing at about 2350. The main rescue center at Stavanger/Sola initiated a search and rescue operation at 0003 on 24 May. At 1610 on 24 May, a report came in that an aircraft from Norsk Flytjeneste had spotted a wreck at Storevatn, 15 km north of Adneram in Sirdal, likely the missing aircraft. A Royal Norwegian Air Force Sea King rescue helicopter reached the wreck around 1800 and found the pilot deceased.
Investigation
The accident site was next to the LYSE VOR, suggesting the pilot had set course for that beacon after passing Vestre Bokn. Based on navigation estimates, the accident likely occurred about 45 minutes after departure, around 1145. Examination of the wreck site revealed no impact marks on the ground (snow) other than at the wreck location itself. The aircraft had struck the ground in a steep nose-first attitude.
Pilot Information
The pilot held a private pilot license (A-certificate) issued 27 August 1974, with ratings for single-engine land aircraft up to 2000 kg, later extended to single-engine seaplanes. The license was valid for night flying and had been renewed on 7 March 1978, valid until 2 November 1978. The pilot also held a radiotelephone certificate. The most recent medical examination was on 22 November 1977, finding the pilot physically and mentally fit. At the last license renewal (7 March 1978), total flight time was 371 hours. According to a journey log, the pilot flew an additional 38 hours 35 minutes in LN-HHM from that date until 22 May, bringing total flight time at the time of the accident to at least 409 hours 35 minutes plus the flight on 23 May. Proficiency checks for land and sea were passed in March and April 1978. The pilot had also begun training for an instrument rating.
Aircraft Information
The aircraft was a single-engine, four-seat Piper Cherokee PA28-140 with fixed tricycle landing gear, built in 1967. After a previous accident in 1974, it was rebuilt using major components from other crashed aircraft. It was entered in the Norwegian Aircraft Register on 24 May 1974 with owner I, Larvik, registration LN-HHM. Ownership transferred on 16 February 1977. The airworthiness certificate was issued 24 May 1974 for categories I a–e, last renewed 9 March 1978, valid to 31 March 1979. Total airframe time at the time of the accident was 1537:35 hours. The engine was a Lycoming O-320-E2A (serial L-14388-27) with 478:00 hours total time, and the propeller was a Sensenich M74DM6. The aircraft was instrumented and approved for VFR flight.
Weather Conditions
The general weather on 23 May 1978 was influenced by a low-pressure system over Germany and high pressure over Russia, directing a moist and unstable southeasterly to easterly airflow of light to moderate breeze strength over southern Norway. In the morning, it was mostly overcast with scattered rain and showers along the Skagerrak coast and eastern areas. Visibility and cloud base were generally over 10 km and 2000–3000 ft. The flow intensified during the morning; from midday, wind strength in places on the Skagerrak coast and inland reached fresh breeze with gale gusts, and precipitation intensified across southern Norway. Visibility and cloud base in some places dropped to 4 km and 600–1000 ft. Cloud tops were estimated at 12,000–13,000 ft; the freezing level was around 7000 ft. Icing index and turbulence were moderate.
Before departure from Karmøy, the pilot contacted the weather office at Sola by telephone at 1045. The conversation was recorded: the pilot asked about conditions for the flight.
Probable Cause
The cause of the loss of control could not be determined with certainty. The commission considered it likely that the aircraft entered an area of clouds, forcing the pilot to fly on instruments, which he did not master, resulting in loss of control.