Overview

The Type 81, or Tribal class, were ordered and built as Sloops to carry out similar duties to the immediate post war Improved Black Swan Sloops and Loch class frigates in the Gulf. In the mid 1960s the seven Tribals were reclassified as second class general-purpose frigates. After the British withdrawal from East of Suez in 1971 the Tribals operated in the Nato North Atlantic sphere with the only update the fitting of Seacat missiles to all by 1977, limited by their single propeller and low speed of 24 knots. In 1979-80 age and crew and fuel shortages, saw them transferred to the stand by squadrons, three being reactivated in 1982 in the Falklands crisis for training and West Indian guardship duties.

The Tribals were designed during the 1950s as a response to the increasing cost of single-role vessels such as the Type 14s. They were first such 'multi role' vessels for the Royal Navy. The fitting of gas turbine boost engines was specifically intended to allow the frigates to almostly instantly leave ports and naval bases in the event of nuclear war. The G6 gas turbine proved reliable and was generally used to leave port during the frigates career and paved the way for gas turbine propulsion to become universal in the RN within 30 years.

The Tribals were the first modern RN ships designed to use a combination of power sources. An additive mix of steam and gas turbine called "COmbined Steam and Gas" COSAG was used. This gave the rapid start-up and acceleration of a gas turbine engine coupled with the cruising efficiency and reliability of the steam turbine. They would cruise on the steam plant and use both systems driving the same shaft for a high-speed "boost". They suffered however from being single-shaft vessels which severely limited manoeuvrability, acceleration and deceleration. The cramped awkward nature of the helicopter pad and handling provision was also exposed in the 1976 Cod War and was a major reason that some Rothesay-class frigates were given further refits in preference to the Tribals and maintained in higher status reserve in the early 1980s limitations on defence spending.

The costs for the Tribals escalated above the costs first envisaged, and the original order of ships, over twenty, was cancelled after the first seven ships had been completed. The ships were rather small, at 110 m, which prevented much modernisation and were always going to be limited by the single-shaft propulsion. The class were still good warships in spite of outdated guns and proved the usefulness of the general purpose frigate concept and gas turbine propulsion, but the average unit costs, of the Type 81s completed in 1963-64 was half million pounds, more than the first 8 Leanders and the over ₤5 million cost of the first Tribal, Ashanti, completed in 1961 was far too high and limited the number built.

Aviation facilities:
Flight deck and no hangar

Aircraft carried
1× Wasp HAS.1

HMS Ashanti

Builder

Laid down

Launched

Commissioned

Deckcode AS

HMS Nubian

Builder

Laid down

Launched

Commissioned

Deckcode NU

HMS Gurkha

Builder

Laid down

Launched

Commissioned

Deckcode GU

HMS Eskimo

Builder

Laid down

Launched

Commissioned

Deckcode ES

HMS Tartar

Builder

HM Dockyard Devonport

Laid down

22. October 1959

Launched

19. September 1960

Commissioned

26. February 1962

29. March 1984

Deckcode TA

HMS Mohawk

Builder

Vickers-Armstrongs Ltd, Barrow-in-Furness

Laid down

Launched

Commissioned

Deckcode MO

HMS Zulu

Builder

Laid down

Launched

Commissioned

Deckcode ZU

History 

- Has anyone more Informations about this Ship's -