HH-52 Seaguard

The Sikorsky HH-52 Seaguard, designated S-62 by the manufacturer, is an amphibious helicopter designed and produced by Sikorsky Aircraft. It was the first amphibious rotorcraft produced by Sikorsky, as well as the first turbine-powered and first amphibious helicopter operated by the United States Coast Guard (USCG). Developed as an independent commercial venture in the late 1950s, the design integrated the dynamic components of the Sikorsky S-55 with a new boat-hull fuselage. The prototype conducted its maiden flight in May 1958. Following a company-funded evaluation program at the Naval Air Test Center in Patuxent River, Maryland, the USCG issued an initial production contract on 21 June 1962. Deliveries of the 99 production aircraft began on 9 January 1963 and concluded on 17 January 1969.

Design

The HH-52 features a watertight, boat-shaped hull fuselage that permits landings on water and snow. Stability on water is provided by two outrigger floats containing retractable landing gear, and the aircraft can deploy an anchor to maintain its position on the water. The helicopter is powered by a single General Electric T58-GE-8B turboshaft engine, derated to 730 shp (540 kW) for the HH-52A. It accommodates a crew of three and can carry up to 12 passengers, six litters, or a 3,127-pound (1,418 kg) payload.

Operational History

The USCG operated the HH-52 primarily for search and rescue (SAR) missions, deploying them from land bases, cutters, and icebreakers. The amphibious design allowed direct water landings to perform rescues without requiring additional flotation gear. During its 26-year service life, the HH-52 fleet rescued over 15,000 people, including 1,200 during the aftermath of Hurricane Betsey in 1965, and assisted during the foundering of the tanker Burmah Agate in 1979. The type was also used for Antarctic logistical support. The HH-52 was retired from USCG service on 12 September 1989, replaced by the Eurocopter HH-65 Dolphin.

Civilian operators utilized the S-62 for passenger service, offshore oil rig transport, and remote logistics. Foreign government and military operators included the Icelandic Coast Guard, the Royal Thai Police, the Philippine Air Force, and Japanese military and coast guard services.

Variants

• S-62: The prototype helicopter, which first flew on 14 May 1958.
• S-62A: The initial production amphibious transport version, powered by a General Electric CT58-110-1 engine and configured for up to 11 passengers.
• S-62B: A single S-62 airframe modified with the main rotor system of the Sikorsky S-58.
• S-62J: The variant produced under license in Japan by Mitsubishi.
• HH-52A Seaguard: The search and rescue variant produced for the United States Coast Guard, with 99 units constructed.