The Grumman J2F Duck was an American single-engine amphibious biplane. The J2F was an improved version of the earlier JF Duck, with its main difference being a longer float. It was used by each major branch of the U.S. armed forces from the mid-1930s until just after World War II, primarily for utility and air-sea rescue duties.  The J2F was used by the U.S. Navy, Marines, Army Air Forces and Coast Guard. Apart from general utility and light transport duties, its missions included mapping, scouting/observation, anti-submarine patrol, air-sea rescue work, photographic surveys and reconnaissance, and target tug.