English: The HO5S-1 was the Marine Corps’ primary medical evacuation helicopter in the last year of the Korean War. Unlike other light helicopters that carried wounded outside on stretchers exposed to harsh conditions, it could internally accommodate two casualties and an attendant. A front-opening bubble gave easy access, while a rear-mounted engine maximized internal carrying capacity. Offset flapping hinges on the rotor improved control and stability, which made it ideal for night flying.

In 1952 this HO5S-1, one of only a few surviving Korean War helicopters, was delivered to Observation Squadron VMO-6, which performed most helicopter medical evacuations for wounded Marines in Korea, transporting over 5,000 seriously wounded personnel. After the war it served with Orlando Helicopter Airways as an air taxi and crop sprayer, and as a platform to test an all-electric drive system.
Picture taken at the National Air and Space Museum's Steven F. Udvar-Hazy Center in Chantilly, Virginia, USA.

Rotor diameter: 10.1 m (33 ft)
Length: 9.1 m (29 ft 9 in)
Height: 2.6 m (8 ft 7 in)
Weight, empty: 802 kg (1,768 lb)
Weight, gross: 1,225 kg (2,700 lb)
Top speed: 185 km/h (115 mph)
Engine: Air-cooled Motors O-425-1, 245 hp

Manufacturer: Sikorsky Aircraft Div., United Aircraft Corp., Bridgeport, Conn., 1952