The U.S. armed forces procured several thousand light observation/liaison aircraft beginning at the start of World War II. Known colloquially as “grasshoppers,” a few hundred were flown by the Navy and (mostly) the Marine Corps.
These were single-engine, high-wing, two-place aircraft, initially developed from commercial designs. Operating from rough, grass fields as well as airfield runways, the planes were employed in a variety of roles: observation, liaison, artillery-fire spotting, casualty evacuation, and “taxi.” In addition, with engines removed and other modifications, they also were used for glider-pilot training.
The most numerous model acquired for the sea services was the Convair OY-1. The Army flew several thousand as the L-5 series, with 306 of the L-5B/E variants going to the Navy and Marine Corps during World War II. These aircraft were designated OY—the “O” indicating observation and “Y” the symbol for Convair, which was created in 1943 by the merger of the Consolidated and Vultee companies.1