C2/2005L Forced landing in Sodankylä on 28 June 2005

At Tankavaara in Sodankylä community, about 15 km north of Vuotso village happened a flight accident on Tuesday June 28th 2005 at 18.26 Finnish time when the engine stopped during flight on a Cessna A185E float plane with registration sign OH-CDO, that was in private ownership and operated by commercial operator. The Accident Investigation Board Finland set June 30th 2005 through its decision Nr C 2/2005 L an investigation committee with investigator Ari Huhtala nominated as the chairman and Kari Siitonen and Juhani Mäkelä as investigation members. The committee called the commercial pilot and psychologist Matti Sorsa, to become a specialist.

The floatplane OH-CDO was intended to be flown from the lake Iso-Hirvanen, situated south of Äänekoski, to the home base at Inari lake. The take-off took place at 15.07. The route went via Kestilä and Utajärvi to west of Pudasjärvi and further slightly east of Ranua to Kemijärvi. The flight continued east of Pyhätunturi and east of Vuotso village towards Tankavaara. The altitude was 400 meters above ground. North of Tankavaara the engine of the aircraft suddenly stopped. The pilot turned immediately to the left into the direction where he came from, trying to reach towards a landing site at Vuotso channel. Simultaneously the pilot tried to start the engine without succeeding. The pilot had to make a forced landing on the marsh. After touchdown the float supports and wings struck some pine trees growing on the marsh. The nose of the right float hit a turf tuft after which the plane turned over the nose into inverted position. The pilot and the passenger were mildly hurt. The people in the vicinity of the accident site started the rescue actions. It was noted in the investigation, that it is specific for a Cessna A185E aircraft, fitted with floats and an external cargo pack, to be unstable around the vertical axis. It can lead to a situation that the airplane tends to fly in a sideslip consequently increasing the fuel consumption and the remaining reduced amount of fuel floats around in the long wing tanks. The day preceding the flight about 180 liters of fuel were filled into the aircraft wing tanks. Before refueling the pilot had estimated that there was about 60 liters of fuel in the tanks. After the refueling there was about 240 liters of fuel in the wing tanks. Moreover 57 liters of fuel were placed in three fuel cans into the external cargo pack underneath the fuselage for a possible refueling during a landing stop. However, the pilot did not check the actual amount of fuel in the wing tanks before the flight. During the flight the pilot monitored the fuel consumption. He thought about a landing stop for refueling, but based on his experience he relied readings off the fuel gages, that indicated that there should have been a sufficient amount of fuel for continuing the flight. The pilot had a strong opinion, based on his experience, that the amount of remaining fuel would be considerably more than it actually was. Also he had relatively limited experience about long cross-country flights and he did not use a flight plan form for preparing the flight. With the help of a form he could have noted, that the amount of fuel now filled up would definitely have required a landing stop for refueling. The investigations did not show any technical defect in the aircraft.

The primary cause of the accident was the flight, carried out without a landing stop for refueling. The flight was stopped when the engine died, caused by a disturbance in the fuel supply to the engine. In spite of his efforts the pilot did not succeed in keeping the engine going and he had to make a forced landing on the marsh.

The accident investigation board does not present any safety recommendations.

C2/2005L Report (pdf, 0.8 Mt)