In February 1940, pilot Lieutenant Jorma "Joppe" Karhunen flight-tested the first B-239 to become operational in Finland. Unfamiliar with the aircraft, he burned out the engine while flying very low at high speed; crashing on a snow-covered field, damaging the propeller and some belly panels. Initially unimpressed, the Finns later witnessed a demonstration by a Brewster test pilot, who was able to stay on the tail of a Finnish Fiat G.50 "Freccia" fighter from Italy; although the Fiat fighter was faster in level flight, the Brewster could out-turn it.