<hi style=afpcap>The Sikorski R-4 was a training helicopter which proved to be successful, resulting in the Air Force issuing a request for a larger type capable of performing the observation role. The basic R-4 design was retained, but with a revised shape as the XR-5. Four prototypes were purchased, with a further 26 YR-5As for service trails and 100 R-5A models, although only 34 were built. These were the first helicopters supplied to the Air Rescue Service. The R prefix was exchanged for the designation in the H series, with the R-5 becoming H-5. Additional models were purchased for the Air Force between 1947 and 1949 with approximately 60 H-5F, G and H versions being ordered. </hi>
