Ton-class minesweeper

HMS Glasserton in 1987
Class overview
Name: Ton-class minesweeper
Builders: John I. Thornycroft & Company, Southampton
Operators:
Preceded by: Algerine-class minesweeper
Succeeded by: River-class minesweeper
In service: 1951–1994 (Royal Navy)
Completed: 119
General characteristics
Type:Minesweeper
Displacement:440 long tons (447 t)
Length:152 ft (46 m)
Beam:28 ft (8.5 m)
Draught:8 ft (2.4 m)
Propulsion:Originally Mirrlees diesel, later Napier Deltic, producing 3,000 shp (2,200 kW) on each of two shafts
Speed:15 knots (28 km/h)
Complement:33
Armament:1 × Bofors 40 mm gun
1 × Oerlikon 20 mm cannon or 1 × M2 Browning machine gun

The Ton-class were coastal minesweepers built in the 1950s for the Royal Navy, but also used by other navies such as the South African Navy and the Royal Australian Navy. They were intended to meet the threat of seabed mines laid in shallow coastal waters, rivers, ports and harbours, a task for which the existing ocean-going minesweepers of the Algerine-class were not suited.

Description

The design of the class was led by the shipyard John I. Thornycroft & Company, and drew on lessons learnt in the Korean War, and numbered 119 vessels. They were diesel powered vessels of 440 tons displacement fully laden, constructed of wood and other non-ferromagnetic materials. Their small displacement and shallow draft gave them some protection against pressure and contact mines, and allowed them to navigate in shallow inshore waters. Primary armament was one Bofors 40 mm gun, although the South African variants also had an Oerlikon 20 mm cannon behind the funnel. RN vessels also had the same but they were gradually removed and an M2 Browning machine gun mounted midships. Sweeping equipment was provided for moored mines and magnetic mines.

Many of the class were converted to minehunters by the incorporation of active rudders and the installation of the Type 193 minehunting sonar and associated equipment, including a very welcome enclosed bridge (the exception being HMS Highburton who retained her open bridge until de-commissioning in the 1970s, this actually becoming a source of manliness to her crew when meeting other Ton crews). These vessels only retained mechanical "Oropesa" sweep capability.

The class served as patrol vessels in Borneo, Malaysia, Northern Ireland and Hong Kong. The minehunters played a significant role in the Suez Canal clearance after the Yom Kippur war. They also provided the backbone of the UK's Fishery Protection Squadron (4th MCM).

Five of the class in Royal Navy Service were permanently converted to patrol craft for service policing Hong Kong's territorial waters in 1971. These vessels, comprising HM Ships Beachampton, Monkton, Wasperton, Wolverton and Yarnton had their minesweeping gear removed and were fitted with a second Bofors 40 mm gun aft of the funnel. They also received new pennant numbers: Beachampton P1007, Monkton P1055, Wasperton P1089, Wolverton P1093 and Yarnton P1096.[1]

It was originally planned to name the ships after insects, with names like Red Ant, Green Cockchafer and so on, but this plan was abandoned and the Royal Navy ships of the class were given names of British towns and villages ending in "-ton", hence the name of the class.

With the rundown of the Royal Navy fleet in the 1960s, many were sent to become base ships for the Royal Naval Reserve allowing reserve crews to get to sea for short periods without a lot of effort to organise a crew of significant size. Some of these had their names changed to reflect the RNR Division they were attached to.

The RNR vessels lasted until the introduction of the River-class minesweepers in 1984. The remainder of the RN ships paid off in the 1990s.

Ships

Royal Navy:

South African Navy:

SAS Pretoria

Royal New Zealand Navy:

See also

References

  1. ↑ Critchley, Mike (1978). British Warships & Auxiliaries. Maritme Books. ISBN 0 9506323 0 9.
  2. ↑ http://www.westernmorningnews.co.uk/careers-brush-death-ndash-driven-man/story-13697573-detail/story.html

Further reading

External links

Wikimedia Commons has media related to Ton-class minesweeper.