page_title: Platt-LePage XR-1
section_title: Operational history
hierarchical_section_title: Platt-LePage XR-1 / Operational history
caption_attribution_description: English: Platt-LePage XR-1A prototype observation helicopter in flight.
context_page_description: The Platt-LePage XR-1, also known by the company designation PL-3, was an early American transverse rotors helicopter, built by the Platt-LePage Aircraft Company of Eddystone, Pennsylvania. The winner of a United States Army Air Corps design competition held in early 1940, the XR-1 was the first helicopter tested by the USAAF, flying in 1941. The flight testing of the XR-1 proved troublesome, and although continued testing showed that the design had promise, other, improved helicopters were becoming available before the XR-1 was ready for service. As a result, the development of the aircraft was terminated in 1945.
context_section_description: Following several months of ground testing, the XR-1 conducted its maiden flight on May 12, 1941, although the aircraft was restrained by a tether for its early flights. On June 23 the aircraft conducted its first free flight, albeit remaining within a few feet of the ground. As flight testing continued and the aircraft's performance envelope was expanded, the XR-1's quickly proved troublesome, the testing showing a variety of troubles with the design. These included issues with the aircraft's controls, insufficient control authority being present, and in addition there were resonance issues with the airframe that made the XR-1 prone to pilot-induced oscillations. The aircraft was modified in an attempt to resolve these issues, and the Army modified Platt-LePage's contract to provide additional funding for improvements to the design, but despite this the XR-1's problems continued. In addition, the company's test pilot, Lou Leavitt, lacked confidence in the design, refusing to fly the aircraft to its full potential. The situation was only resolved when Colonel H. Franklin Gregory, director of rotor-wing projects for the Army Air Forces, flew the aircraft himself, reaching 100 mph (160 km/h) on his first flight in the aircraft.
  With the worst of the aircraft's problems believed to have been resolved, the XR-1 was submitted for service testing by the Army Air Forces in 1943. During the course of the Army's evaluations, the XR-1's empennage failed during structural testing, the surfaces being strengthened as a result and testing, following the repairs, resuming in 1944. Despite the modifications to the design, however, the XR-1 still proved to be deficient in control authority. In July 1943, the XR-1 program suffered a setback when the aircraft crashed, seriously injuring test pilot Jim Ray, who had replaced Leavitt following the latter's dismissal from the company. The crash was caused by an inspector's error in leaving a suspect part on the aircraft, the rotor hub failing in flight as a result of the decision. The aircraft was repairable, but it would be a year before the XR-1 was ready to fly again.
  Testing was, however, able to continue in the meantime, as Platt-LePage had re-negotiated the XR-1 contract to cover a second flight-test aircraft. Built to a revised and improved version of the XR-1's design and designated XR-1A, the second aircraft had flown for the first time in May 1943. The XR-1A featured a revised cockpit covering compared to that of the XR-1, with the area of glazing being increased for improved visibility, and the pilot and observer's positions being reversed, the pilot now seated in the rear cockpit. During flight testing the XR-1A was found superior in flight performance to the XR-1; however, the controls were still proving troublesome, although the worst of the bugs did seem to have been worked out.
  Following a cross-country flight to Wright Field in Ohio from Platt-LePage's Pennsylvania plant, testing of the XR-1A continued until a mechanical failure in the rotor hub led to a crash landing on 26 October 1944, the company deciding to sell the wreckage for scrap.
  The XR-1, having been repaired in the meantime, was once again flying, and a contract had been awarded to Platt-Lepage for the construction of seven pre-production aircraft, to be built to an improved version of the XR-1A design, and designated YR-1A. Motivated by Congressional concerns about potential favouritism towards Sikorsky Aircraft, which had in the meantime been given a contract for development of an improved version of their VS-300 experimental helicopter, the contract called for delivery of the first YR-1A to the Army in January 1945. However, due to continued financial and flight-testing problems, Platt-Lepage proved incapable of meeting this schedule.
  Although the XR-1's problems seemed to be approaching resolution by late 1944, the protracted development of the aircraft meant that alternative, improved helicopters, such as Sikorsky's XR-4, less expensive and more maneuverable than Platt-LePage's aircraft, were becoming availabl
caption: The improved XR-1A
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