The Dale class consisted of three tankers

Oil tanker

An oil tanker, also known as a petroleum tanker, is a merchant ship designed for the bulk transport of oil. There are two basic types of oil tankers: the crude tanker and the product tanker. Crude tankers move large quantities of unrefined crude oil from its point of extraction to refineries...

 chartered for service for the Royal Fleet Auxiliary

Royal Fleet Auxiliary

The Royal Fleet Auxiliary is a civilian-manned fleet owned by the British Ministry of Defence. The RFA enables ships of the United Kingdom Royal Navy to maintain operations around the world. Its primary role is to supply the Royal Navy with fuel, ammunition and supplies, normally by replenishment...

 in 1967. They served for a number of years supporting Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 and allied fleet operations, during which one, Ennerdale, was lost. The remaining two were returned to their original owners in the mid 1970s.

Overview

Three large modern tankers, built to varying designs in the mid-1960s, were charted by the Royal Fleet Auxiliary to support naval operations east of the Suez Canal

Suez Canal

The Suez Canal , also known by the nickname "The Highway to India", is an artificial sea-level waterway in Egypt, connecting the Mediterranean Sea and the Red Sea. Opened in November 1869 after 10 years of construction work, it allows water transportation between Europe and Asia without navigation...

, in the waters of the Indian Ocean

Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

 and the Far East

Far East

The Far East is an English term mostly describing East Asia and Southeast Asia, with South Asia sometimes also included for economic and cultural reasons.The term came into use in European geopolitical discourse in the 19th century,...

. They were given traditional RFA names, reusing three names that had been used for the Second World War-era Dale class oiler

Dale class oiler

The Dale class were a class of replenishment oilers taken up for service with the Royal Fleet Auxiliary, supporting the Royal Navy during the inter-war period. The went on to see action during the Second World War and supported British and allied fleet units in Cold War conflicts such as the Korean...

s. They were not fitted with equipment to allow them to replenish ships at sea, and were classified instead as 'Mobile Reserve Tankers'.

The smallest, RFA Ennerdale was also the shortest lived. She hit a coral reef and sank off Port Victoria

Victoria, Seychelles

Victoria is the capital city of the Seychelles and is situated on the north-eastern side of Mahé island, which is the main island of the archipelago. The city was first established as the seat of the British colonial government...

 on 1 June 1970. The wreck was subsequently destroyed with explosives fired from Wessex helicopters

Westland Wessex

The Westland Wessex is a British turbine-powered version of the Sikorsky S-58 "Choctaw", developed under license by Westland Aircraft , initially for the Royal Navy, and later for the Royal Air Force...

 to prevent an oil spillage from threatening the Seychelles

Seychelles

Seychelles , officially the Republic of Seychelles , is an island country spanning an archipelago of 115 islands in the Indian Ocean, some east of mainland Africa, northeast of the island of Madagascar....

. RFA Derwentdale was returned to her original owners in 1974, but RFA Dewdale remained in service until 1977. During this time Dewdale saw service with the Aden

Aden

Aden is a seaport city in Yemen, located by the eastern approach to the Red Sea , some 170 kilometres east of Bab-el-Mandeb. Its population is approximately 800,000. Aden's ancient, natural harbour lies in the crater of an extinct volcano which now forms a peninsula, joined to the mainland by a...

 task force during the British withdrawal in 1967, and was then active then on the Beira Patrol

Beira Patrol

The Beira Patrol was a blockade of oil shipments to Rhodesia through Beira, Mozambique, resulting from United Nations trade sanctions after Rhodesia declared its independence...

s. She was the last to leave service with the RFA, being returned in 1977 and commencing service under her old name of Edenfield.

Ships

Name	Pennant	Builder	Previous name	Fate
Derwentdale	A221	Hitachi	Halcyon Breeze	Returned in 1974
Dewdale	A129	Harland and Wolff Harland and Wolff Harland and Wolff Heavy Industries is a Northern Irish heavy industrial company, specialising in shipbuilding and offshore construction, located in Belfast, Northern Ireland....	Edenfield	Decommissioned in September 1977
Ennerdale	A213	Kieler Howaldstwerke	Naess Scotsman	Wrecked on 1 June 1970