A Finnish military training plane failed to come out of a spin during an air show stunt and crashed, killing the pilot hours after an air show disaster claimed more than 40 lives in West Germany. The crash Sunday at Kleine Brogel Air Base, 68 miles northeast of Brussels, was the second such air accident this month in Belgium. Witnesses said one of the two Redigo aircraft taking part in the show organized by the Belgian air force was unable to come out of a spin during stunt manuevers and plunged to the ground. Officials said the pilot, Ari Piippo, was flying too low to enable him to safely eject from the plane, which belonged to the state-owned Finnish aircraft maker Valmet. Valmet recently sold 10 Redigo airplanes to Finland's air force for training purposes. On Aug. 7, a Belgian pilot died when his Mirage-5 jetfighter crashed at an air show, also organized by the Belgian air force, at Leopoldsburg, seven miles west of Kleine Brogel Air Base.