The RK-26 was a German twin-seat biplane trainer designed at the end of the 1920s. In December 1930 an agreement was signed for license production of the aircraft by the Swedish aircraft manufacturing company ASJA as the Flygvapnet was in need of a new trainer. They later ordered 25 aircraft and it was given the designation Sk 10. The plane was in service between 1932 and 1945 but was unpopular, as changes in the design that made the aircraft much heavier than the original, changing the flight characteristics drastically. Of the 25 delivered aircraft, 18 were w/o and this is the only survivor.