Incident
On 3 March 2007, a scheduled VFR flight operated by Luftverkehr Friesland Brunzema und Partner KG departed from Pärnu Airport (EEPU) at 14:08 local time, bound for the island of Ruhnu (EERU). The flight had been postponed several times since 26 February 2007 due to adverse meteorological conditions, which had caused supply difficulties on the island.
Flight Details
The flight was conducted in uncontrolled airspace. On board were the pilot, two passengers, and 520 kg of cargo. According to the weather briefing obtained by telephone from Kuressaare at 14:00, cloud height in Kuressaare (EEKE, 36 nautical miles northwest of Ruhnu) was 600 feet, while at Ruhnu it was reported as 180 meters (approximately 540 feet). During the uneventful initial flight at 1500 feet, the coast and ice border remained clearly visible, with no signs of icing observed.
Approach and Accident
The pilot intended to land on Runway 32 and decided to fly low from east to west across the runway to check the windsock and runway condition. While approaching the island, the pilot descended at 150 ft/min with low power settings and flaps extended by one notch. During descent, visibility deteriorated both horizontally and vertically, and the flight entered instrument meteorological conditions (IMC). The descent continued in clouds, resulting in a loss of visual contact with the ground and horizon. The aircraft emerged from the clouds over the coast at a very low altitude, estimated by the pilot as 100–120 feet. Attempting to maintain a safe altitude and speed, the pilot added power. Simultaneously, a stall warning activated, and seconds later, the lower fuselage contacted treetops before colliding with terrain at 14:36. The engines continued producing power until the collision, after which the pilot set them to idle.
Aftermath
The accident site was located 0.24 nautical miles northeast of the Runway 32 threshold on uneven, forested ground covered with young pinewoods. The pilot and passengers escaped the aircraft without assistance and sustained no injuries.
Probable Cause
The investigation established the following causes of the accident: 1. The pilot could not maintain a safe flight altitude when approaching Ruhnu aerodrome. 2. The pilot continued the descent in spite of IMC. Contributing factors to the accident included high motivation to perform the flight, inadequate weather information from ground services of Ruhnu aerodrome, and inadequate aeronautical oversight at the destination airport.