This second of two stamps honoring aviation pioneers features Lawrence and Elmer Sperry. Elmer was awarded more than 400 patents. He revolutionized flying with such devices as the gyro compass and speed-direction indicators. Lawrence helped to develop and test such aviation innovations as the automatic pilot, retractable landing gear, and the first guided missile in the form of an aerial torpedo. Elmer died in 1930, and Lawrence drowned in 1923, after crashing on a flight over the English Channel.