SH-34 / HSS Seabat
A decade of helicopter development by Sikorsky peaked with the introduction of its S-58 model. Sikorsky developed the S58 in response to a US Navy requirement for an anti submarine warfare helicopter. What resulted was the S58, which features a single Wright R1820 radial piston engine mounted in the nose, one of the largest fuselages to be designed for a single piston powered helo and a raised flightdeck.It was designated HSS-1 by the Navy which signed the first contract on June 30, 1952. The XHSS1 aircraft first flew on March 8, 1954, and was followed by 1,821 production helicopters of the S-58 series. Large numbers of S58s were built to serve with the US Navy in anti submarine warfare roles as the SH34G and SH34J Seabat, and in utility roles.
In 1951 the Navy was searching for an ASW helicopter capable of operating from battleships and cruisers. The Bell-manufactured XHSL-1 helicopter was chosen originally in lieu of a Sikorsky aircraft in 1950 to meet this requirement, but had been in the developmental stage for well over a year. Many problems arose during the XHSL-l's construction which resulted in an increase in weight and size to the point where it became completely unacceptable to the Navy. At this point Sikorsky submitted its design to BuAer as a solution to the Navy's waning ASW program. The helicopter was described as a HRS-4; a modified HRS with a larger engine and cabin in addition to a differently designed tail cone and landing gear. But as the design evolved, so many changes were made to the basic HRS that it could not be considered a modification, but rather a completely different helicopter.
Basically, the Navy's requirement for an ASW helicopter specified that it be capable of carrying a pilot, copilot, sonar equipment and ordnance, and two crewmen. It was to have a three-hour flight duration and be compatible for storage in, and operating from, the same class of ships (battleships and cruisers) as the XHSL. By February 1952, the CNO had become convinced that the Bell XHSL-1 would not meet the ASW specifications nor be ready for delivery within an acceptable length of time. On the 27 February 1952, the CNO directed BuAer "to proceed without delay with a program for the development of the Sikorsky HRS aircraft with the large engine -- ASW configured ." The first flight of Sikorsky's HRS- 4 was predicted to occur in November 1953 with the delivery of the first production aircraft scheduled for January 1955.
The HSS-1 was accepted by the Navy in February 1954 and first delivery was to Helicopter Anti-Submarine Squadron 3 in August 1955. Production was completed in January 1970. The HSS-1 Seabat was designed for ASW search and attack, with the capability of operating from cruisers and carriers. The Marine Corps quickly followed with an order for a similar version, designated the HUS-1 Seahorse. It was reconfigured for the mission of transport and utility. The HUS version was first accepted in January 1957 and assigned to Marine Helicopter Transport Squadron (Light) (HMR(L)) 363 the following month. In 1962 the HSS-1 series was redesignated SH-34G/J for its ASW role, and UH-34G/J for a utility role. The HUS-1 series was also redesignated, UH-34D or E, depending on the configuration.
The HSS/HUS aircraft had single rotor systems with a 56-foot rotor diameter, four blades and a tail rotor. Depending on their configuration, they carried a crew of two and 12 passengers or a crew of two to four. The helicopters were specifically designed to be stored aboard ship; the main rotor blades could be folded aft and the entire rear fuselage and tail rotor folded forward, for stowage. The helicopters typical cruise speed was 98 mph with a range at full payload of 247 miles.
During the Korean War, the US Navy expanded its use of helicopters in its antisubmarine warfare program. The S-58 was designed for that mission. Introduced in 1954, it was able to carry increasingly sophisticated sonar equipment. The Marines felt that they would be useful for transporting troops from ship to shore and the corps soon had its own model, designated the UH-34D. It was used mainly for assault missions.
The HSS-1N Seabat made its first public flight on May 27, 1958, at NAS Corpus Christi. It was the first helicopter capable of day and night ASW operations under instrument flight conditions, which was a major breakthrough for helicopter operations. It was an HUS-1 from HMR(L)-262 that recovered the first American in space, Alan B. Shepard, after splashdown in the ocean on May 5, 1961. The Seabat and Seahorse were also involved in many significant operations in Vietnam, and were especially remembered for their utility role in medical evacuation.
First delivery of the HSS-1 to the Naval Air Training Command was on May 6, 1955, for use in the fleet introduction program. In February 1962, HT-8 received its first HSS-1. The training program was then lengthened from 10 to 14 weeks for advanced training in the OHSS-1, and also in the H04S and HUP. HSS-Is (UH-34G) continued in service with HT-8 until July 1970 when they were phased out of the squadron, while HSS-1s (UH-34D/G) remained in the Navy inventory until March 31, 1974.