Bittern Class (1935) Sloop

The Bittern Class of Escort Sloops were the sixth class of such vessels designed since a program of replacing WW1 sloops had begun in the mid-1920's. They were a small class of only three ships but consolidated Escort Vessel ideas which had evolved during the 1920's

They followed on from the Grimsby Class (1934) SL.

By this time sloop design had evolved into a class of convoy escort which could provide effective anti-submarine and anti-air cover. There was no equivalent of HMS Bittern in any other Navy. In a ship of only modest size the anti-air armament was almost up to that of a Cruiser.

Bittern was used to evaluate and prove the use of fin stabilisation to provide a more stable gun platform. It was not proved effective in the minds of the doubters, who were mostly at sea. But the Admiralty held to the view that only operational use would improve its effectiveness. The result was that fin stabilisation was fitted in some but not all of the classes which followed.

The original Bittern was completed as an Admiralty Yacht with additional accommodation fitted in place of the X and Y guns, and renamed Enchantress. As WW2 drew nearer the extra accommodation was removed but instead of mounting the originally designed 4.7in guns, additional AA guns were fitted in their place.

Stork was completed as an unarmed surveying vessel. In 1938 she was taken out of survey use and rearmed to the same standard as Bittern.

As WW2 progressed modifications and additions were made to their armament.

The term Sloop was officially dropped in 1937 when Escort Sloops were re-rated as Escort Vessels, but the term continued in unofficial use.  An initial requirement to conduct minesweeping duty was reduced as the roles of minesweeping and convoy escort diverged. The required endurance was determined as the longest passage probable as a convoy escort which was the UK to Freetown, 3,500 miles plus a margin for operations. Say about 5000 miles at 10kts.


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This page last edited - 04 February, 2013.

Copyright Ian M King, except where otherwise indicated.