Lee de Forest tests first airborne radiotelephone equipment, Long Island, 1916

Lee de Forest holds a wireless radio receiver at Mineola Field, Long Island, New York, 1916. On August 4, 1910, de Forest and his pilot, Elmo Pickerell, had first made headlines when they successfully demonstrated radio transmission from Pickerell's Wright Model B and a portable ground station. After further developments, in 1916 de Forest demonstrated vacuum tube radiotelephone (voice) equipment, with a trailing antenna, in an airplane at Mitchell Field. Soon after, the equipment was transferred to the U.S. Army Signal Corps. In his autobiography, De Forest claimed this to be "the first radiotelephone sets ever installed in an airplane." This photograph is among more than 600 images in the extensive Lee de Forest Papers at History San José.