landing signal officer

Landing Signal Officers (LSOs) are naval aviators specially trained to control the approach and landings of airplanes aboard aircraft carriers. In the U.S. Navy, carrier operations began with USS Langley (CV-1) in 1922. Because pilots approaching the short, narrow deck had a poor view of the landing area, an officer was assigned to stand portside aft, facing the incoming plane, and holding colored flags to signal corrections. With standardized signals, the landing pilot could be informed whether he was at the correct altitude, course, and speed, leading to a "cut" signal to reduce power and land the airplane. In a properly executed landing, the aircraft's tailhook snagged an arresting wire that brought the plane to an abrupt halt.
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