Sikorsky Aircraft
First Flight: February 12,1947
The Sikorsky S‑52 was a four‑place utility helicopter that was evaluated by the U.S. Army as the YH‑18 and saw service with the U.S. Navy as the HO5S‑1. It was the first American helicopter to have all‑metal rotor blades and, in its earlier S‑52 civilian version, set three international helicopter speed and height records. These 1948 records were 129.6 mph over a 3‑kilometer course, 122.75 mph over a 100‑kilometer course, and 21,220 feet absolute height.
The semi‑monocoque fuselage was a pod‑and‑boom type constructed of aluminum‑magnesium alloy, with a three‑bladed, all‑metal main rotor and a two‑bladed anti‑torque tail rotor driven by a six‑piston, 245‑hp air‑cooled engine. A quadricycle fixed landing gear was fitted.
The U.S. Army evaluated four YH‑18s in 1950 but did not procure any for service use. The U.S. Navy purchased 89 S‑52‑3s as the HO5S‑1 for general utility duties, all of which were delivered by 1953.
| Aircraft Specifications | |
|---|---|
| Rotor Diameter | 33 ft |
| Fuselage Length | 29 ft |
| Maximum Speed | 105 mph |
| Cruise Speed | 90 mph |
| Height | 8 ft 8 in |
| Empty Weight | 2,000 lbs |
| Gross Weight | 2,770 lbs |
| Engine | 245 hp Franklin 0-425-1 |
| Acquisition Source | Peter Wright Donation |