First flown in 1920, the FVM Tummelisa (Thumbelina, the female counterpart of Tom Thumb) served in the Swedish air force as a single-seat trainer until 1935. The factory designation was E.1. In 1926 it was given the military designation Ö1 for an 'exercise aircraft' or advanced trainer. This airframe belonged to a second batch built in 1928 and made its last flight in 1962.