Sikorsky S-61 / HSS-2 / H-3 Sea King ![]() Westland Sea King AEW
Provision for 381kg of weapons, including homing torpedoes.
The prototype HSS-2 flew on 11 March 1959 and ten pre-production YHSS-2 trials aircraft (147137 to 147146) followed completing service trials in 1960. During flight testing, it proved its ability to hover over one point for more than three hours continuously, and to complete patrols of up to four hours with large fuel reserves. Redesignated as YSH-34A in 1962.
The US Navy ordered the first ten S-61B/HSS-2 for delivery starting in September 1961 and the Sea King began to reach fleet squadrons in September 1961. The helicopters were later redesignated SH-3A Sea King. One of the first production models set up a world speed record of 339 km/h on 5 February 1962. The HSS-2 held all four of the other major international helicopter speed records for distances up to 620 miles.
![]() HSS-2
In the SH-3A version 255 were produced, while eight more (150610 to 150617), ordered as HSS-2Z and subsequently re-designated VH-3A and -3C, were assigned to the special American Presidential Department for personnel transport and evacuation services in case of emergency. First flying on 18 September 1962 eight modifications were produced (147141, and 150610-150617) and 11 new production (159350-159360). The YSH-3A Sea King and SH-3A were USN anti-sub warfare helicopters. About 250 were built, including 148038, 152104/152139, and 153532/153537, of which one was converted with a modified fuselage to S-61F, three as CH-3B, and three to the USAF as NSH-3A (62-12571/12573)
.
One set a world helicopter speed record of 192.9mph on 17 May 1961, piloted by P L Sullivan and B W Witherspoon. A highly modified SH-3A set a world helicopter speed record of 210.64mph on 5 February 1962 piloted by R Grafton.
Nine of the SH-3As were transformed into RH-3As with minesweeping equipment, first flying on 2 February 1965, and three were used by the USAF for missile site support and drone recovery. They were the only H-3 to have cargo doors on both sides. A small number of RH-3A minesweeper variants entered service in 1964. Some were to became UH-3A drone targets. Repowered RH-3A were designated RH-3D.
Another 12 SH-3As were converted into the HH-3A for battlefield rescue work, and were fitted with two Emerson TAT-102 turrets mounted at the rear of the two spontoons, and an in-flight refuelling probe.
The H-3 designation was applied to various versions of the S-61 basic design, including S-61B, -61D, -61F, and -61R.
The HH‑3E of the USAF Aerospace Rescue and Recovery Service has an inflight‑refuelling probe, hoist and much special role gear, and has also been developed into the radar‑equipped HH‑3F Pelican advanced search‑and-rescue helicopter for the US Coast Guard.
In April 1962, the USAF leased HSS-2 / CH-3B (62-12574 to 62-12576), transformed into 27-seat transport aircraft for services linking the Texas Towers radar installations. Another three S-61As upgraded to CH-3B were purchased for this purpose (62-12571 to 62-12573). One later transferred to the USN. Until 1990, the Library of the USAF Museum erroneously filed details of these aircraft under the H-38 designation. Sixteen S-61A-4s with 31 seats were acquired by the Royal Malaysian Air Force (S-61A-4 Nuri) and nine by the Danish Air Force for rescue work. Danish deliveries were made from December 1964 to May 1965. One went to a civil operator. A total of 38 S-61A were built. From 1966, the anti-sub SH-3A was superseded by the SH-3D, which had a 1044kW / 1419shp T58-GE-10 turbine replacing the original 932kW T58-GE-8Bs, and new electronics. Seventy-two were built; prototype 152139, 152690/152713, 154100/154123, 156483/156506, 158724/158725, 158874/158875, 159026/159029, 159053/159056, and 161207/161212. In addition, several SH-3As were converted to this standard (148998, 151544, 152139, and 153532/153537). VH-3D referred to a conversion.
The first SH-3D delivered in June 1966 was one of six ordered by the Spanish Navy. This was followed by another four for the Brazilian Navy and 73 for the US Navy, and ordered by Argentina.
The 105 SH-3G were USN SH-3A and -3B converted to utility configuration. They were further modified as SH-3H with new anti-sub warfare equipment fitted and UH-3H.
Two SH-3Gs were converted to YSH-3J as prototypes for the LAMPS III program.
The essentially similar CH-124, assembled by United Aircraft of Canada, was supplied to the Canadian navy. The Royal Canadian Navy was the first export customer, ordering 41 of the type. The Royal Norwegian air force acquired S-61A helicopters without ASW equipment for rescue duties, and the Royal Malaysian air force acquired S-61A-4 Nuri helicopters equipped to carry 31 troops or operate in the SAR role. Acquired originally for re-supply of its radar stations, the US Air Force CH-3B was essentially a de-navalised SH-3, but the CH-3C that was ordered in November 1962 introduced a number of major changes, including a rear loading ramp. Originally conceived as XHR3S-1 and allocated the company designation S-61R, the prototype flew on 17 June 1963 and the first CH-3C delivery was made on 30 December 1963. The small flotation sponsons were replaced by larger sponsons and the tail wheel was replaced by a retractable nose wheel. Only one S-61R was built for civilian use and seventy-five CH-3C models were built for the USAF (62-12561/12570, -12577/12582, 63-9676/9691, 64-14221/14237, 65-5690/5700, -12511, and -12777/1280). The R model has an 80 hp auxiliary power unit. An engine change from 969kW T58-GE-1s to 1119kW T58-GE-5S produced the CH-3E in February 1966. Most were later converted to CH-3E or HH-3E standards.
![]() Sikorsky CH-3C 1493
One CH-3C (62-12581) was temporarily used to test de-icing equipment as CH-3C.
Some were later converted to HH-3E standard for the USAF Aerospace Rescue and Recovery Service, being provided with armour, self-sealing fuel tanks, retractable inflight-refuelling probe, rescue hoist and 12.7mm machine-guns for defensive purposes; this was the 'Jolly Green Giant' as used in Vietnam. These aircraft have all been replaced by the HH-60. The US Coast Guard operated the HH-3F Pelican, which had advanced electronic equipment for SAR duties, but lacked the self-sealing tanks, armour and armament of the HH-3E. Ordered in August 1965, the US Coast Guard a special version gave all-weather capability, which could safely land on water. The Pelican was virtually identical to the HH-3E, apart from the lack of protection, armament and other military equipment. It had an AN/APN-195 search radar on the port side of the nose. Forty were operated; 1430/1438, 1467/1497 plus 12 USN (158847/158858). These gave way to the HH-60J Jayhawk.
![]() Sikorsky HH-3F 1493 A heavylift version of this helicopter, nicknamed the 'Payloader', carried cargoes as heavy as 4990kg.
A total of 210 HSS-2 were built (148033 to 148052, 148964 to 149012, 149679 to 149738, 149893 to 149934, 150618 to 150620, and 151522 to 151557) powered by two T58-GE-8 engines. Production continued as SH-3A and ultimately 245 were built.
Civil versions for passenger operations were developed initially as the non-amphibious S-61L which, with a lengthened fuselage to seat up to 30 passengers, was first flown on 6 December 1960 and was FAA-approved on 2 November 1961. S-61Ls entered service with Los Angeles Airways on 1 March 1962. The S-61L is a landplane model, although its hull is sealed against the possibility of making an emergency landing on water, and all undercarriage units are non-retracting. It seats 28 passengers in the standard airline seating layout and carries a flight crew of 3.
![]() Sikorsky S-61L N302Y
Three S-61Ls operated by Los Angeles Airways had each exceeded 10,000 flight hours by February 1968.
Three S-61L was followed by the essentially similar S-61N that was, however, an amphibious version with a sealed hull and stabilising floats that housed retractable landing gear; it was first flown on 7 August 1962 and is still in widespread civil use. The type received FAA certification - the first for a twin-turbine commercial helicopter - in November 1961 and since October 1964 has been cleared for all-weather operation. Production examples have 1500shp CT58-140 shaft turbines.
Customers up to January 1968 for the S-61N have been British European Airways (four); Greenlandair (four); Pakistan International and San Francisco & Oakland (three each); Helibuss of Norway (two); and Ansett/A.N.A., Brunei Shell Petroleum, the Canadian Dept. of Transport, Elivie of Italy, Japan Air Lines, KLM, Nitto Airways and Petroleum Helicopters Inc. (one each).
BEA used a sole S-61N on the 35 mile route between Land’s End and the Scilly Isles.
![]() BEA S-61N
The S-61N is the civil version of the military S-61C, and is some four foot longer. The sole example was used by Grumman Corp for many years in support of flight operations from Long Island.
The S-61R differs from the original S-61 in that it has a more boat-type hull, modified to take a rear loading ramp, while the two sponsons have been replaced by two stub wings set farther back, into which the rear members of the tricycle landing gear retract.
The prototype was built by the company as a private venture and flown with a civil registration on 17 June 1963, almost one month ahead of schedule. However, the USAF had already placed an order with Sikorsky in February of that year for 22 aircraft, designated CH-3C, and they began to receive the first helicopters at the end of 1963. Subsequent orders brought the total number for the USAF to 133.
S-61R
The CH-3C was used in the Vietnam War for rescuing pilots who had been shot down and came to be nicknamed the "Jolly Green Giant". It was given more powerful T58-GE-5 turbines from February 1965 and redesignated CH-3E. The uprated "Green Giant" could carry 26 troops or 15 wounded, or vehicles of equivalent weight, and could also be armed with two Emerson turrets on the leading edges of the two stub wings.
Forty-two CH-3Es were built (66-13291/13296, 67-14702/14725, and 69-5798/5812), in addition to which 41 CH-3Cs were modified to this standard.
![]() Sikorsky CH-3E ex-CH-3C 63-9676
The USAF also asked for specific modifications to be made to this helicopter to meet the demands of the Vietnam War: application of armour; use of supplementary fuel tanks for extended flights; self-sealing internal fuel tanks and a telescopic in-flight refuelling probe. Two of the first aircraft of the 50 to be built in the HH-3E rescue version became famous in 1967 by flying non-stop from New York to Paris (for the Air Show), covering the 6870km journey with nine refuellings by airtankers. Eleven were converted from CH-3E (66-13284/13290, and 68-8282), plus several CH-3Cs.
The CH-3E could seat up to 30 troops or carry 2270kg of cargo.
In 1975 CH/HH-3Es became the first helicopters in the US Air National Guard. Variants of Sikorsky's S-70 have replaced S-61Rs in US service.
S-61 production by Sikorsky came to an end after two decades on 19 June 1980 and military S-61s served in 30 countries, plus with the US Air Force, Navy, Marine Corps and Coast Guard. Sikorsky built 794 S-61s between 1959 and 1980.
The only foreign license-holder for the S-61R / CH-3 / HH-3 was Agusta, who began producing it in 1974. The 22 aircraft built by Agusta were all delivered to the Italian Air Force as replacements for the amphibious Grumman Albatross used for search and rescue missions at sea. In Britian, the Royal Navy also chose the S-61 to replace its Wessex. In 1959 Westland acquired the license to build the Sikorsky S-61B, to replace the Wessex in the antisubmarine role. The licence agreement allowed Westland to use the airframe and rotor system of the Sikorsky SH-3 Sea King as the basis for a new ASW helicopter for the Royal Navy. The Royal Navy specification called for a British powerplant with different characteristics from the original one, different electronics and a wide range of mission capabilities. Westland adopted a pair of Rolls-Royce Bristol Gnome turbines for their version of the Sea King, with fully computerized controls and largely British-made ASW equipment. The resultant helicopter is readily identifiable by the dorsal radome of the all-weather search radar. Other avionics systems include Plessey dipping sonar, Marconi Doppler navigation radar and Sperry & New-mark instrumentation.
Following test and evaluation of prototype and pre-production aircraft assembled from Sikorsky-built components, the first British-built HAS Mk.1 production Sea King flew on 7 May 1969 and the first squadrons were formed the following August. At that time, the Sea King HAS.Mk 1 was similar to the Sikorsky SH‑3D Sea King, but powerplant comprised two Rolls-Royce Gnome H.1400 turboshaft engines. More significantly, Westland had adapted the large cabin as a tactical compartment for ASW operations, this meaning that the British Sea King was able to operate as an independent unit in an ASW role.
![]() Royal Navy HAS.1 Sea King
The Sea King is not a truly amphibious vehicle, in that any length of time spent in water would irrevocably damage some items of equipment on the hull. It is therefore only designed to land on water in an emergency, the boat-type hull being guaranteed watertight for 15 minutes. The two lateral sponsons contain flotation bags to improve buoyancy.
Westland delivered 56 in 1969‑72. The HAS.Mk 1 machines were later modified to Sea King HAS.Mk 2 standard with more powerful Rolls‑Royce Gnome engines improved equipment, 21 Sea King HAS.Mk 2 helicopters also being built new.
![]() Sea King HAEW Mk.2
Westland has built over 200 Sea Kings, including the Sea King Mk.1, 2 and 5 for the Royal Navy, 22 for the German Navy (Mk.41), 11 for the Norwegian Air Force (Mk.43) and 12 for the Australian Navy (Mk.50). Westland also produces a tactical transport version of the Sea King, known as the Commando, which first flew on 12 September 1973. It has the same power plant as the Sea King, a fixed landing gear, can carry up to 28 troops or 2,720kg of cargo, and may be armed for assault duties. The Commando Mk 1 is also known as the Sea King Mk 70 and is basically a stripped-out Sea King HAS.Mk 1. Westland flew the first commando Mk 2 on 16 January 1975. No customer has ever specified the Mk 2's optional underwing hardpoints. Commando Mk 2Bs have extra seats for two flight attendants. Commando Mk 1 and Mk 2 versions have been supplied to Egypt and Qatar. Qatar's Mk 3s have Sea King-like undercarriage sponsons. 17 were initially delivered to the Royal Navy and at least another 30 to Egypt and Qatar. Deliveries for the Sea King and Commando totalled 326 by the end of 1993.
Sea King HAS.Mk 1
Initial ASW version for Royal Navy; since updated to Sea King HAS.Mk 2 by Royal Navy; 56 completed
Sea King HAS.Mk 2
ASW/SAR version for Royal Navy with uprated Gnome H.1400-1 turboshafts; 21 completed
Sea King HAR.Mk 3
SAR version for Royal Air Force with Gnome H.1400-1 turboshafts; 16 delivered in 1979 plus three in 1985; upgraded to
HAR.Mk 3A
HAR.Mk 3A
Standard through addition of greatly improved avionics, navigation and communications gear
Sea King HC.Mk 4
Version of Commando Mk 2 for Royal Navy; combines folding rotor and tail of Sea King, non-retractable landing gear of Commando and Gnome H.1400-1 turboshafts; last aircraft delivered in 1990, total production 89; some aircraft modified with RWR, missile approach warning system, chaff/flare dispensers, tactical navigation equipment, and NVG cockpit for Gulf War operations
Sea King Mk 4X
Two aircraft, basically as HC.Mk 4; for development use by RAE Famborough
Sea King HAS.Mk 5
Developed ASW/SAR version for Royal Navy with Gnome H. 1400-1 engines and advanced avionics; all Sea King HAS.Mk 2 aircraft upgraded to this standard along with 30 new-build aircraft delivered between 1980 and 1986
Sea King HAS.Mk 6
Substantially improved anti-submarine warfare version for Royal Navy comprising five conversions from Mk 5 standard and 25 new aircraft
Sea King Mk 41
SAR version for Federal German navy with H.1400 turboshafts – 22 built
Sea King Mk 42
ASW version for Indian navy with H.1400 turboshafts – 24 built based on the RN version except for the communications equipment
Sea King Mk 42A
ASW version for Indian navy with H.1400-1 turboshafts
Sea King Mk 42B
Anti-ship version for Indian navy, H 1400-1 turboshafts and equipped to carry Sea Eagle missiles
Sea King Mk 43
SAR version for Norwegian air force with H.1400 turboshafts – 11 built
Sea King Mk 43A
SAR version for Norwegian air force with H. 1400-1 turboshafts
Sea King Mk 45
ASW version for Pakistan navy with H.1400 turboshafts – 6 built
Sea King Mk 47
ASW version with H.1400-1 turboshafts, ordered by Saudi Arabia for Egyptian navy
Sea King Mk 48
SAR version for Belgian air force with H.1400-1 turboshafts - 5 built
Sea King Mk 50
Multi-role version for Royal Australian Navy; developed from Sea King HAS.Mk 1 but with H. 1400-1 turboshafts; two additional but similar aircraft ordered in 1983 were allocated designation Sea King Mk 50A - 12 built
Commando Mk 1
Version with H.1400 turboshafts ordered by Saudi Arabia for Egyptian air force
Commando Mk 2
Version with H. 1400-1 turboshafts for Egyptian air force
Commando Mk 2A
Version as Commando Mk 2 for Qatar Emiri air force
Commando Mk 2B
Version as Commando Mk 2 with VIP interiors for Egyptian air force
Commando Mk 2C
Version as Commando Mk 2B for Qatar Emiri air force
Specifications
HSS-2
Engines: 2 x 1250 shp General Electric T-58-GE-8.
Main rotor diameter: 62 ft
Main rotor disc area: 3019 sq.ft
Length: 54 ft 9 in
Width over floats: 15 ft 8 in
Empty weight: 11,194 lb
Normal takeoff weight: 17,768 lb
Fuel capacity: 575 gal
Max speed: 148 mph at SL
Hover ceiling OGE: 6000 ft
Range: 535 mi
Weapon load: 840 lb
S-61L
S 61L
Engine: 2 x General Electric CT58-140-2 turboshaft, 1,118kW / 1500 shp
Rotor dia: 62 ft 0 in (18.9 m)
Length: 72 ft 7 in (22.12 m)
Height: 17 ft (5.18 m)
Max TO wt: 19,000 lb (8620kg)
Max level speed: 146 mph (235 kph)
Fuel: Forward 796 litres, 757 litres.
Total fuel capacity 1,553 lt
Range: 292 mi
Passenger capacity: 30
YHSS-2
Engines: two General Electric T58-GE-6
Rotor diameter: 62'0"
Length 54'9"
Max speed: 166 mph
H-3 (Model S-61)
Engines: two GE T58-GE-8C/F turboshafts
Main rotor: six-blade
Main rotor diameter: 62'0"
Length: 54'9"
Max speed: 160 mph
Cruise: 133 mph
Range: 625 mi
Ceiling: 10,800'
CH-3C
HH-3E
Westland Sea King HAS Mk.5
Engine: 2 x Rolls-Royce Gnome H.1400-1 turboshaft, 1238kW
Main rotor diameter: 18.9m
Length with rotors turning: 22.15m
Height: 4.72m
Max take-off weight: 9525kg
Loaded weight: 6202kg
Cruising speed: 208km/h
Range: 1230km
Armament: 4 x Mk.46 torpedos or 4 x Mk.11 depth charges
Westland HAEW Mk.2
Main rotor diameter: 18.90m
Fuselage length: 16.69m
Height: 4.74m
Max take-off weight: 9500kg
Cruising speed: 208km/h
Hovering ceiling, OGE: 2500m
Range with max fuel: 1200km
Duration of patrol: 4-4.5h
Crew: 4
S-61N
|