From the museum website:

BY SIKORSKY

The HH-3E is the USAF version of the Sikorsky S-61 amphibious transport helicopter developed for the U.S. Navy. The USAF initially operated six Navy HSS-2 (SH-3A) versions of the S-61 in 1962, eventually designating them CH-3A/Bs. They were so successful the USAF ordered 75, modified as CH-3Cs, featuring a new rear fuselage design with a ramp for vehicles and other cargo. The first CH-3C was flown on 17 June 1963. When 41 CH-3Cs were updated with more a powerful engine in 1966, they were redesignated as CH-3Es. Forty-five were newly manufactured. Later, 50 CH-3Es were modified for combat rescue missions with armor, defensive armament, self-sealing fuel tanks, a rescue hoist, and in-flight refueling capability. They were redesignated HH-3Es and used extensively in Vietnam under the name “Jolly Green Giant.”

Warner Robins Air Logistics Center was responsible for all program and logistics support for the USAF H-3 fleet worldwide. The aircraft on display was delivered to the USAF in November 1967 and assigned to the 56th Air Commando Wing at Nakhon Phanom RTAFB, Thailand and served in Southeast Asia until returning to the United States in September 1971. It then served with various units and deployed to Desert Storm in 1990 with the 71st Special Operations Squadron from Davis-Monthan AFB, Arizona. It was later assigned to the 41st Aerial Rescue and Recovery Squadron at Patrick AFB, Florida where its primary mission was providing Space Shuttle rescue support during launches. The helicopter was retired to the Museum of Aviation for display in August 1994.

SPECIFICATIONS: Rotor diameter: 62 ft. Length: 73 ft. Height: 18 ft. 1 in. Weight: 22,050 lbs. loaded Armament: Provisions for two .50-cal guns Engines: Two General Electric T-58-GE-5 turbo shaft engines of 1,500 hp. ea. Crew: Three Cost: $796,000 Serial Number: 67-14703

PERFORMANCE: Maximum speed: 177 mph. Cruising speed: 154 mph. Range: 779 miles with external tanks Service ceiling: 21,000 ft.