YMS-1-class minesweeper

From Wikipedia, the free encyclopedia
  (Redirected from YMS-1 class minesweeper)
Jump to navigation Jump to search

USS YMS-324 in San Francisco Bay, c. 1945–46
Class overview
Name: YMS-1
Builders: 35 yacht builders[1]
Subclasses: YMS-136, YMS-446
In commission: about March 1942[1] - 13 December 1957[2]
Completed: 481[1]
Cancelled: YMS-482YMS-500
Active: 0
Lost: 32[3]
General characteristics
Type: Minesweeper
Displacement: 270 tons
Length: 136 ft (41 m)
Beam: 24 ft 6 in (7.47 m)
Draft: 8 ft (2.4 m)
Speed: 15 knots (28 km/h)
Complement: 32

The YMS-1 class of auxiliary motor minesweepers was established with the laying down of YMS-1 on 4 March 1941. Some were later transferred to the United Kingdom as part of the Second World War Lend-Lease pact between the two nations. One ship eventually made its way into the Royal Canadian Navy postwar.


The design for the class had a displacement of 270 tonnes. The ships had a length of 136 feet (41 m) a beam of 24 ft 6 in (7.47 m), and a draft of 8 ft (2.4 m). The vessels were capable of 15 knots (28 km/h; 17 mph), being powered by two 440 shp (330 kW) General Motors (Cleveland) 8-268A, 2-cycle diesel engines which drove two shafts.

The ships had a complement of 32. Their armament comprised one single 3-inch/50 caliber gun mount, two 20 mm anti-aircraft guns and two depth charge projectors.


There were two mostly cosmetic sub-types of the class, sometimes referred to as classes themselves

YMS-135 subclass[edit]

This subclass was identical but had only one stack rather than two, and consisted of YMS-135YMS-445, YMS-480, and YMS-481.

YMS-446 subclass[edit]

This subclass was also identical but had no stacks, and comprised YMS 446YMS 479.


Eighty vessels of the class were ordered from US yards for transfer under Lend-Lease to the United Kingdom as the BYMS-class minesweeper. Another 53 built for the US Navy (hull numbers 137 to 284) were transferred as further BYMS and another 17 were delivered later.

Other exports[edit]

France received 31 YMS-class minesweepers during World War 2, with one (D202, formerly YMS-77) being sunk by a mine in 1944. France kept its YMS-class ships in service after the end of the war,[4] with seven remaining in service in 1962, used as training ships in the École Navale and as experimental vessels. Three ships of the class were transferred from France to South Vietnam in 1954, while another was transferred to Madagascar in 1961.[5]




  1. ^ a b c Priolo, Gary P. (2006). "Auxiliary Motor Minesweeper (YMS), British Motor Minesweeper (BYMS) Index". NavSource Online. NavSource Naval History. Retrieved 20 December 2007.
  2. ^ Radigan, Joseph M. (2006). "Ruff (MSC[O] 54), ex-AMS-54, ex-YMS-327". NavSource Online. NavSource Naval History. Retrieved 20 December 2007.
  3. ^ For both YMS-1 and BYMS classes a total 40 were lost. Of those 40, 32 were YMS-1 class. (See: "YMS class Minesweepers". Uboat.net. Retrieved 20 December 2007.)
  4. ^ Masson 1969, pp. 59, 61–53.
  5. ^ Blackman 1962, p. 94.

External links[edit]