Sikorsky S-48

The Sikorsky S-48/VS-327/R-5 model was a follow-on to the successful R-4 helicopter. It was designed to meet a 1942 U.S. Army Air Forces (USAAF) requirement for a larger more capable observation helicopter as well as a British requirement. The XR-5 helicopters featured a 48 foot 3 bladed fully articulated main rotor and a 3 bladed tail rotor powered by the reliable Pratt and Whitney 450 hp R985-AN-5 radial engine. The S-48 had a 2 place tandem cockpit with the observer in the forward position and the pilot aft.  Four Experimental XR-5 helicopters were initially built with a fifth XR-5A ordered later. The first flight was on August 18, 1943.