Sport Trainer-Military

摘要

Originally designated ST (Sports Trainer) the Ryan PT-20/STM-2 was developed as a civilian aerobatic aircraft and first flew in 1934. By 1939 it was accepted into the US Army Air Corps and this was when it received the ST(M) for Military designation. Prior to the outbreak of World War Two, the little Ryan became a successful export to many countries around the world. The outbreak of war only served to increase demand.