Sikorsky S-61R


The Sikorsky S-61R is a twin-engine helicopter used in transport or search and rescue roles. A developed version of the S-61/SH-3 Sea King, the S-61R was also built under license by Agusta as the AS-61R. The S-61R served in the United States Air Force as the CH-3C/E Sea King and the HH-3E Jolly Green Giant, and with the United States Coast Guard as the HH-3F "Pelican".

Development

The Sikorsky S-61R was developed as a derivative of their S-61/SH-3 Sea King model. It features a substantially revised fuselage with a rear loading ramp, a conventional, though watertight, hull instead of the S-61's boat-hull, and retractable tricycle landing gear. The fuselage layout was used by Sikorsky for the larger CH-53 variants, and by the much later S-92.
In 1957, Sikorsky engineers were working on a new model for the United States Navy to replace the H-34s, used for anti-submarine warfare. Designated the HSS-2, this helicopter would enter service as the SH-3 Sea King. On 9 January 1958, General Randolph M. Pate, Commandant of the Marine Corps, wrote to the Chief of Naval Operations requesting procurement of modified HSS-2s to replace the Marines' UH-34s. General Pate recommended that the transport version be designated the HR3S. Funds for aircraft procurement were short in 1958 and progress on the design of the HR3S was slow. Detailed specifications for the new helicopter were published by CNO on 7 March 1960. Four items were specified:
While the design of the assault transport version was in final review, the HSS-2 was being tested. Problems were encountered with its stability and the main transmission was limited to 2,000 horsepower, even though at peak power the engines could produce more. In July 1959, before the selection of the HR3S, Vertol Aircraft Corporation had given presentations to the Marines of their new model, the 107A, and in late March 1960, with Sikorsky engineers still wrestling with problems in the HSS-2 and designing a ramp for the HR3S, Vertol dispatched a YHC-1A to the Landing Force Development Center at Marine Corps Base Quantico, for assessment by six Marine pilots. The Marine assessment endorsed the acquisition of the Vertol 107M. On 20 February 1962, the Marines selected the Vertol 107M as the winner of the HRX competition, and it entered Marine service as the CH-46 Sea Knight.
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Notwithstanding the loss of the HRX competition, Sikorsky built an S-61R prototype as a private venture, with its first flight in 1963. During its development, the US Air Force placed an order for the aircraft, which was designated CH-3C. The Air Force used the CH-3C to recover downed pilots. The CH-3E variant with more powerful engines would follow in 1965.
The improved HH-3E variant would follow later, with eight built, and with all 50 CH-3Es converted to this standard. Known as the Jolly Green Giant, the HH-3E featured protective armor, self-sealing tanks, a retractable inflight refueling probe, jettisonable external tanks, a high-speed hoist, and other specialized equipment.
In 1965, the U.S. Coast Guard ordered a version designated HH-3F Sea King for all-weather air-sea rescue. The Pelican featured search radar with a nose antenna radome offset to port, and water landing capability.
Italian Agusta built a S-61R variant under license, named AS-61R. Agusta produced 22 helicopters for the Italian Air Force. The company claimed it could re-open the production line in 36 months to build additional AS-61 helicopters.

Operational service

United States

USAF variants served in numerous air rescue squadrons and aerospace rescue and recovery squadrons of the Military Airlift Command, rescue squadrons of the Air Combat Command and other USAF major commands worldwide. The aircraft was also used by a number of Air Force Reserve Command and Air National Guard rescue squadrons. All USAF HH-3Es, to include Air Force Reserve and Air National Guard, were retired in the 1990s and replaced by the current HH-60G Pavehawk.
The HH-3F Pelican was a dependable workhorse for the US Coast Guard from the late 1960s until it was phased out in the late 1990s. All USCG HH-3Fs were replaced by the HH-60J Jayhawk and those aircraft have since been upgraded to the MH-60T Jayhawk version.

Transatlantic flight

Between 31 May and 1 June 1967, two HH-3Es of the United States Air Force made the first nonstop flight across the Atlantic Ocean by helicopter. Departing from New York in the early hours, the two helicopters arrived at the 1967 Paris Air Show at Le Bourget after a 30 hr 46 min flight. The operation needed nine in-flight refuelings. Both helicopters were later lost in combat operations in Southeast Asia in 1969 and 1970.

Italy

began production in 1974 and delivered 22 helicopters as replacements for the Grumman HU-16 Albatross used for SAR missions at sea. Italian Air Force AS-61R helicopters performed SAR missions under designation HH-3F in time of peace and C/SAR in time of crisis or during military assignment. All helicopters were operated by the five flights of the 15° Stormo Stefano Cagna and deployed in four bases across Italy.
From 1993 15° Stormo performed support missions to evacuate civilians during natural catastrophes and disasters in Italy. 15º Stormo was also engaged with SAR missions in the hostile zones of the several operations abroad where Italian Armed Forces were deployed - Somalia, Albania, Bosnia, Kosovo, Iraq and Afghanistan.
The Italian Air Force phased out the HH-3F on 26 September 2014, replacing them with the AgustaWestland AW139 in the SAR role

Variants

;S-61R
;HR3S-1
;S-61R-10
;S-61R-12
;CH-3C
;CH-3E
;HH-3E Jolly Green Giant
;MH-3E
;VH-3E
;HH-3F "Pelican"
;AS-61R

Operators

Civil

Argentina