Archie League (August 19, 1907 – October 1, 1986) is generally considered the first air traffic controller. Before the installation of a radio tower, he was a flagman who directed traffic via flags. His first "control tower" consisted of a wheelbarrow on which he mounted a beach umbrella for the summer heat. In it he carried a beach chair, his lunch, water, a note pad and a pair of signal flags to direct the aircraft. He used a checkered flag to indicate to the pilot "GO", i.e. proceed, or a red flag to indicate the pilot should "HOLD" their position.