Staff Writer (Updated: 6/15/2016):
Visibly, the Choctaw wasn't going to win any design awards based on looks alone. It was a far cry from being the best looking of Cold War creations but it was an vast upgrade from the utilitarian approach of the H-19 Chickasaw before it. Design of the H-34 was stout, featuring a large set rounded nose with a raised flightdeck. The pilot and co-pilot sat in their raised positions ahead of the powerplants and above and forward of the passenger/cargo cabin. Entry into the system was provided for by a large rectangular access door (sliding aft) located on the starboard side of the lower fuselage. The underside of the fuselage maintained a predominantly straight appearance, giving the Choctaw its unique profile. The undercarriage was fixed and consisted of two main landing gears supported by exposed struts and a single tail wheel. The main landing gear systems were positioned just forward of the passenger cabin and fitted with a large single wheel each. Power was generally supplied by a Wright R-1820-84 Cyclone radial engine delivering up to 1,525 horsepower and driving a four-bladed main rotor and a four-bladed tail rotor. While the operational crew amounted to two personnel, the cabin had space for up to 16 combat-ready troops, 18 passengers or 8 medical litters. A top speed of 123 miles-per-hour was listed as was a range of 182 miles.
The Choctaw lived a long service live under many guises beginning as the HSS-1 "Seabat" for the United States Navy (in its Anti-Submarine Warfare role). This was coupled with the similar HUS-1 "Seabat" utility transport. The "Seabat" series consisted of US Navy Choctaws built to anti-submarine warfare specifications initially appearing as three Sikorsky S-58 models for evaluation as XHSS-1 prototype systems. The XHSS-1 then became the YHSS-1 before ultimately being re-designated to YSH-34G. The first production models became the HSS-1 "Seabat". The HSS-1N "Seabat" was of note as it was a dedicated bad weather/night version fitting improved autopilot and avionics systems. Seabats fell under the designation of SH-34 beginning in 1962.
The "Seahorse" series was operated primarily by the US Marine Corps and the US Coast Guard. These were noted by their designation of "HUS" as in the HUS-1, HUS-1A, HUS-1G, HUS-1L and the HUS-1Z. These eventually became the UH-34 "Seahorse" series beginning in 1962. The United States Coast Guard operated the Choctaw from 1959 through 1962.