The Piasecki HUP Retriever was a compact tandem-rotor helicopter developed for the U.S. Navy in the late 1940s and used for search and rescue, personnel transport, and utility missions aboard aircraft carriers and other naval vessels. Its distinctive design featured two large overlapping rotors mounted at the front and rear of the fuselage, eliminating the need for a tail rotor and allowing the helicopter to operate in the confined spaces of a carrier deck. Entering Navy service in 1949, the HUP was particularly valuable for rescuing aviators who went down at sea and could use a rescue hoist to lift survivors aboard. The Retriever also served during the Korean War and was operated by the U.S. Army and several foreign militaries. With its unusual rounded fuselage and tandem-rotor configuration, the HUP Retriever represents an important early chapter in the development of shipboard helicopters and naval search-and-rescue aviation.