River class minesweeper

Orwell in the Bay of Biscay en route to Gibraltar, 1990
Class overview
Name:	River-class
Builders:	Richards Dry Dock and Engineering Limited
Operators:	Royal Navy Brazilian Navy Bangladesh Navy Guyana Defence Force Coast Guard
Cost:	£4.6 million each
In commission:	1984–2001
Completed:	12
General characteristics
Type:	Minesweeper
Displacement:	850 long tons (864 t) standard 890 long tons (904 t) full
Length:	47 m (154 ft 2 in)
Beam:	10.5 m (34 ft 5 in)
Draught:	3.1 m (10 ft 2 in)
Propulsion:	2 shafts, Ruston 6RKC diesels, 3,040 bhp (2,267 kW)
Speed:	14 knots (16 mph; 26 km/h)
Complement:	5 officers and 23 ratings (accommodation for 36: 7 officers and 29 ratings)
Armament:	• 1 × Bofors 40 mm gun Mark 3 • 2 × 7.62 mm L7 GPMGs

The River class was a class of minesweeper built for the British Royal Navy in the 1980s, designated Fleet Minesweepers (MSF).

Design

The Rivers were built with a traditional steel hull to a design based on a commercial offshore support vessel. The class was designed to be operated as deep sea team sweepers, to combat the threat posed to submarines by Soviet deep-water buoyant moored mines codenamed "Cluster Bay".
The River Class MSF was equipped with the Wire Sweep Mark 9 (WS 9) which was capable of performing Extra Deep Armed Team Sweeping (EDATS). Operating in pairs (or a number of pairs in formation), they towed a sweep between the two ships that followed the profile of the bottom and cut the mooring wires of the mines; these released mines would then be destroyed on the surface with gunfire. The WS 9 was able to be used for mechanical sweeping in this manner or influence sweeping whereby a transducer was towed through the water generating noise, both acoustic and electro-magnetic, that simulated a larger high value unit. The Rivers were also armed with a single 40 mm Bofors gun on the manually operated World War II-era Mark III mounting, and two L7 GPMGs.
The concept was refined in the chartered trawlers HMS St David and HMS Venturer, and a total of twelve vessels, all named after British rivers, were constructed by Richards Shipbuilders at Lowestoft and Great Yarmouth at an approximate unit cost of £4.6 million. The class was designed to operate in deep water and ocean environments, if necessary for long periods of time without support. The complement was 5 officers, 7 Senior Ratings, and 16 Junior Ratings, although additional accommodation meant that a total crew of 36 could be borne for training purposes.

Ships

Ship	Commissioned	RN / RNR Use	Fate
Waveney (M2003)	12 July 1984	South Wales Division RNR - HMS Cambria	Sold to Bangladesh BNS Shapla (M95)
Carron (M2004)	30 September 1984	Severn Division RNR - HMS Flying Fox	Sold to Bangladesh BNS Shaikat (M96)
Dovey (M2005)	30 March 1985	Clyde Division RNR - HMS Graham	Sold to Bangladesh BNS Surovi (M97)
Helford (M2006)	7 June 1985	Northern Ireland Division - HMS Caroline	Sold to Bangladesh BNS Shaibal (M98)