On 14 Jan 1942, XR-4 made first flight; delivered to Air Corps 30 May 42, 4 mos 20 days after first flight and 14 mos after contract award. By 24 Jul, XR-4 had accumulated 100 hrs of flight test time. Shortly after, 2 competitors in rotary wing competition enabled under Dorsey Act, XR-3 and YO-60--both jump-takeoff autogiros--were dropped. 21 Dec 42, contract awarded and XR-4 became first US production helicopter; 131 delivered. On same date, contract awarded for 5 XR-5s--twice the size of XR-4 and carried twice the useful load. 455 ordered, but only 65 delivered by VJ Day and further deliveries were cancelled. R-5 was largest helicopter until then to enter production. Evaluated for many uses and missions--pipe laying, geodetic survey, photography, mapping, breaking of ice jams, calibration of radar, and forestry service. Established several world's records and remained in service until 1954. Later, several modified versions built for Navy and Air Force and primarily used for rescue; first to be used by Air Rescue Service. Remained in service until early 60s.