Eiri-Avion PIK-20

The PIK-20 sailplane was designed at the Helsinki University of Technology by Pekka Tammi, with advice from Ilkka Rantasalo and Raimo Nurminen. The prototype first flew on 10 October 1973. It was produced initially by Molino Oy who were taken over by Eiri-Avion Oy (currently Eirikuva Oy) between 1974 and 1980. Later, production was taken over by the French company, Siren SA, under the name Siren PIK-20.

At first the PIK-20 was classified as a Standard Class glider, which at the time allowed either flaps or air-brakes for landing approach control. The specification of the Standard Class required the air-brakes or flaps to be capable of keeping the speed below the maximum speed in a vertical dive. However at high speed great force was needed to fully lower the flaps and so the PIK-20 was equipped with a geared crank handle.

The first prototype finished 13th in the World Gliding Championships in Waikerie in January 1974 but it performed impressively. (The low placing was caused by a poor decision on the first day of the competition.) This yellow prototype glider (OH-425) can be seen in movie named "Zulu Romeo - Good start" about this 1974 World Gliding Championship. The glider was then produced at the rate of two to three per week.

The rules of the Standard Class were changed again to allow the flaps and ailerons to move together (flaperons) and for intermediate settings of the flaps between landing mode and zero. The result was the PIK-20B which won British, American and Finnish National Championships in 1975. In 1976 Ingo Renner won the World Championship with a PIK-20B and second and third places were also taken by this type. Most owners of PIK-20A converted to the B's flaperon arrangements. Carbon fiber spars later became standard.

Another change in the rules prohibited lift-enhancing devices in the Standard Class; and introduced a racing class or 15-metre class which did permit lift-enhancing devices. As a result, the PIK 20D with trailing-edge flaps was produced for the new 15-metre class.

The name PIK is an acronym for Polyteknikkojen Ilmailukerho, the flying club of the Student Union of Helsinki University of Technology.

A fire in the factory June 1977 dented production briefly but by then 200 gliders had been sold. Production continued until about 1985 with the D and E versions with over 400 examples of the type having been completed.