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Warship Wednesday11th October 2023

HMS HYDRA – Ocean Survey Ship

HMS HYDRA was a Hecla class Survey Ship, constructed by Yarrow & Co shipbuilders at Blythswood, Glasgow.

The Hecla class (3 ships, plus 1 Improved Hecla) were the first RN survey ships to be designed with a combined oceanographical and hydrographic role. The hull was strengthened for navigation in ice. The fore end of the superstructure incorporated a Land Rover garage and, a helicopter hangar at the aft end with adjacent flight deck.

HYDRA was laid down in May 1964, launched on 14th July 1965 and commissioned into the Royal Navy on 5th May 1966.

HYDRA was 260 ft overall length x 49 ft wide and displaced 2733 tons (full load). The ships company was 118 (14 officers and 104 ratings). There was accommodation on board for 123 (19 officers and 104 ratings).

Powered by 3 x Paxman ‘Ventura’ 12-cylinder turbocharged diesels providing 3,840 bhp. Driven by a 2000 shp electric motor through a single propellor. Max speed on trials was 14.5 knots.

Sufficient fuel was carried to give a range of 20,000 miles at 9 knots. H7YDRA had the capability of operating independently of shore support for long periods.

HMS HYDRA was docked at Chatham Dockyard five times between 1967 and 1971 for Refit Docking and DED’s (Docking and Essential Defects) work.

In 1968 HMS HYDRA participated in Chatham Dockyard Navy Days. A record crowd of 65,000 attended the two-day event, and HYDRA was visited by approx. 16,500 members of the public.

HYDRA was placed on RN Disposal list 1986 an handed over to Indonesia 18th April 1986 for refit. On completion of the refit, she was commissioned into Indonesian Navy on 10th September 1986 as Survey Ship “DEWI KEMBAR”.


In Greek and Roman mythology, Hydra is a huge sea serpent-like monster with nine heads, one of which is immortal. It lived in a lake called Lerna, allegedly the entrance to the underworld. Hydra’s blood and breath was deadly poisonous.

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