Piasecki HUP Retriever

The design was a product of a competition by the U.S. Navy in 1945 for a compact utility/rescue helicopter to operate from ships including aircraft carriers, battleships, and cruisers. prototypes—designated PV-14 by the factory and XHJP-1 by the Navy—were built and subjected to a side-by-side flight evaluation against the 3 prototypes of the Sikorsky XHJS-1; however, the XHJS was fundamentally a scaled-up version of the Sikorsky H-5, and the increased weight and size magnified the design's problems with maintaining proper weight and balance under varying loading conditions. The Piasecki won the competition, the aircraft was ordered for production as the HUP-1. During a flight demonstration of its capability to withstand high g-force, the type became the first helicopter to perform a loop, albeit unintentionally. ==Operational history==

The aircraft first entered service in February 1949 with the delivery of the first of 32 HUP-1 aircraft to the US Navy. Edo tested a HUP-2 with a fiberglass hull and outrigger floats for amphibious operations. An upgraded version of the HUP-2 was built for the US Army and designated as the H-25A Army Mule, but most were quickly withdrawn from Army service and converted for naval use under the designation HUP-3. The aircraft were used aboard HMCS Labrador for search and rescue and varied utility duties, and were later used to support construction at Distant Early Warning Line radar sites. Operated in association with Classic Rotors, the accident aircraft was the only airworthy example in the world. The National Transportation Safety Board attributed the crash to "The pilot’s failure to maintain clearance from powerlines during en route flight." ==Variants==

;XHJP-1 :Prototype, powered by a Continental R-975-34 piston engine, equipped with large sloping endplate fins on the horizontal stabilizers. Piasecki-Vertol designation was PV-14. 2 ;H-25A Army Mule :Utility transport helicopter for US Army, similar to HUP-2 but powered by a Continental R-975-46A piston engine, and fitted with large doors, power-boosted controls, and strengthened floors. ;UH-25B :HUP-2 redesignated after 1962. ;UH-25C :HUP-3 redesignated after 1962. ==Operators==

; • Royal Canadian Navy ; • French Navy ; : • United States Army • United States Navy ==Surviving aircraft==

; this aircraft was later traded to Classic Rotors. This aircraft has been restored to the appearance of 51-16621, the first Royal Canadian Navy HUP-3. Netherlands • UH-25B (HUP-2), 130076 (construction number 253) – Baris Business Park roadway roundabout in Rotterdam. This aircraft was originally used by the US Navy and was later transferred to the French Navy. United Kingdom • UH-25C (HUP-3), 51-16622 – displayed at The Helicopter Museum in Weston-super-Mare, England, wearing Canadian markings. United States ;On display ;;H-25A Army Mule • 51-16616 – United States Army Aviation Museum in Fort Rucker, Alabama. ;;HUP-1 • 124915 – USS Hornet Museum in Alameda, California. ;;UH-25B (HUP-2) • 128479 – American Helicopter Museum in West Chester, Pennsylvania. • 128517 – Wings of Freedom Aviation Museum in Horsham, Pennsylvania. • 128519 – Intrepid Sea, Air & Space Museum in New York City, New York. • 128596 – Flying Leatherneck Aviation Museum in San Diego, California. • 130059 – USS Midway Museum in San Diego, California. • 130082 – on the deck of the USS Iowa Museum in San Pedro, California. ;;UH-25C (HUP-3) • 147595 – Pima Air & Space Museum in Tucson, Arizona. • 147600 – Air Zoo in Kalamazoo, Michigan. • 147607 – National Naval Aviation Museum in Pensacola, Florida. • 147628 – Mid-America Air Museum in Liberal, Kansas. • 51-16621 – Classic Rotors in Ramona, California. As of December 2019, this is the only Piasecki Helicopter-manufactured aircraft with valid FAA aircraft registration. This former Royal Canadian Navy aircraft is reportedly the last HUP/H-25 capable of being restored to airworthy condition; it was exchanged in 2000 by the Canadian Museum of Flight for unflyable HUP-2 128529, which was subsequently traded again in 2002 to the Shearwater Aviation Museum and repainted as 51-16621. • 130053 – Stored at Quartzsite, Arizona. • 130063 - Stored at New England Air Museum in Windsor Locks, Connecticut. ==Specifications (HUP-2)==