Aggressive-class minesweeper
US built ocean minesweepers
USS Constant (MSO-427) in 1988
Class overview
Name Aggressive class
Operators
Subclasses Onversaagd class
In commission 1953–Present
Completed 53
Active 1
Retired 52
Preserved 2
General characteristics
Type Minesweeper
Displacement 853 tons (full load)
Length 172 ft (52 m)
Beam 35 ft (11 m)
Draft 10 ft (3 m)
Propulsion
4 × aluminum block Waukesha diesels, 2,400 bhp (1,800 kW)
2 × shafts
2 × controllable pitch propellers
Speed 14 knots (26 km/h; 16 mph)
Complement 7 officers, 70 enlisted
Sensors and processing systems AN/SQQ-14 mine hunting sonar
Armament
The Aggressive -class minesweepers are a class of US-built minesweepers . They are designated as MSO (Mine Sweeper Ocean), distinguishing them from the smaller coastal MSCs and inshore MSIs. Besides the US Navy , this class of vessels has also been used by the Belgian Navy and the Norwegian Navy , among others.
Background
Minesweeping, or the disposal of naval mines , by these vessels is performed in different ways:
Sweeping proper, with an underwater cable cutting the mooring cables of moored mines. The mines then come to the surface and are destroyed by gunfire.
Acoustic sweeping, with a towed device producing noise to trigger acoustic mines.
Magnetic sweeping, with a towed device producing a magnetic field to trigger magnetic mines. To protect the minesweeper itself against magnetic mines, the hull and superstructure of the ship are made of wood. Other components are made of non-magnetic materials, and any magnetic materials are strictly controlled.
Construction and disposition
Of the 53 constructed for the United States Navy, 10 were built at Higgins Corp ., New Orleans , Louisiana, 9 at J.M. Martinac Shipbuilding Corp. , Tacoma, Washington , 8 at Wilmington Boat Works Inc., Wilmington, California , 6 at Luders Marine Construction Co. of Stamford, Connecticut , 4 at Broward Marine Inc, Fort Lauderdale, Florida , 4 at Martinolich Shipbuilding Co., San Diego , California, 3 at Burger Boat Company, Manitowoc, Wisconsin , 3 at Colberg Boat Works , Stockton, California , 2 at Fulton Shipyard , Antioch, California , 2 at Norfolk Naval Shipyard and 2 at Seattle Shipbuilding and Drydocking Co., Seattle , Washington .
33 of the class were decommissioned before the mid-1970s. Four ex-USN ships were sold to the Republic of China Navy 1994 and re-classed as Yung Yang -class minesweepers . They were still in active service in 2012. USS Implicit was decommissioned 30 September 1994 in Tacoma, Washington and was the last Aggressive -class minesweeper in US Navy active service.
A crewman monitors a mine detection and classification sonar console aboard the ocean minesweeper USS Conquest
A crewman monitors a mine detection and classification console aboard the ocean minesweeper USS Conquest
A
paravane used for mine sweeping aboard USS
Conquest
USS Illusive lowers an acoustical device during an exercise.
USS Illusive lowers a different acoustical device for training.
USS Illusive deploys a mineweeping cable.
USS Constant deploying the "mag-tail", used to simulate the magnetic field of a vessel, are towed behind the ship to trigger magnetic mines.
A remote control mine-seeking system, Super Sea Rover, aboard USS Conquest
USS Esteem deploys a marker, for marking mines or mine fields.
Units
Ship Name
Hull no.
Builder
Commission– Decommission
Fate
Link
Aggressive [1]
422
Luders Marine Construction Co. of Stamford, Connecticut
1953–1971
Sold for scrap 1980
Avenge
423
Luders Marine Construction Co. of Stamford, Connecticut
1954-1970
Destroyed by fire, sold for scrapping 1969
Bold [2]
424
Norfolk Naval Shipyard
1953-1971
Sold for scrap 1981
Bulwark [3]
425
Norfolk Naval Shipyard
1953-1971
Sold for scrap 1980
Conflict [4]
426
Fulton Shipyard , Antioch, California
1954-1973
Sold for scrap 1973
Constant
427
Fulton Shipyard, Antioch, California
1954-1992
Sold for scrap 2001
Naval Vessel Register
428 - 431 were US Dash -class minesweepers
Dynamic
432
Colberg Boat Works, Stockton, California
1953-1971
Sold or loaned to Spain as Guadalete M41, 1971.
Naval Vessel Register
Engage
433
Colberg Boat Works, Stockton, California
1953-1991
Scrapped 2002
Naval Vessel Register
Embattle
434
Colberg Boat Works, Stockton, California
1954-1972
Sold to be scrapped 1976, privately held until scrapped by USACE in 1993.
Naval Vessel Register
Endurance
435
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1954-1972
Sold for scrap 1973
Naval Vessel Register
Energy
436
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1954-1972
Loaned to Philippines 1972 Sold for scrap 1977
Naval Vessel Register
Enhance
437
Martinolich Shipbuilding Co., San Diego, California
1955-1970 1971-1991
Sold for scrap 2000
Naval Vessel Register
Esteem
438
Martinolich Shipbuilding Co., San Diego, California
1955-1970 1971-1991
Sold for scrap 2000
Naval Vessel Register
Excel
439
Higgins Corp ., New Orleans, Louisiana
1955-1992
Sold for scrap 2000
Naval Vessel Register
Exploit
440
Higgins Corp ., New Orleans, Louisiana
1954-1993
Sold for scrap 2002
Naval Vessel Register
Exultant
441
Higgins Corp ., New Orleans, Louisiana
1954-1993
Sold for scrap 2002
Naval Vessel Register
Fearless
442
Higgins Corp ., New Orleans, Louisiana
1954-1990
Sold for scrap 1992
Naval Vessel Register
Fidelity
443
Higgins Corp ., New Orleans, Louisiana
1955-1989
Sold for scrap 1990
Naval Vessel Register
Firm
444
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1954-1972
Loaned to Philippines 1972 Scrapped 1977
Naval Vessel Register
Force
445
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1955-1973
Sunk after a fire
Naval Vessel Register
Fortify
446
Seattle Shipbuilding and Drydocking Co., Seattle , Washington
1954-1992
Scrapped 2002
Naval Vessel Register
Guide
447
Seattle Shipbuilding and Drydocking Co., Seattle , Washington
1955-1972
Sold for scrap 1973
Naval Vessel Register
Illusive
448
Martinolich Shipbuilding Co., San Diego, California
1953-1990
Sold for scrap 1993
Naval Vessel Register
Impervious
449
Martinolich Shipbuilding Co., San Diego, California
1954-1991
Scrapped 2002
Naval Vessel Register
450 - 454 built at Bellingham Shipyards Co., Bellingham, Washington for France, not necessarily Aggressive -class ships.
Implicit
455
Wilmington Boat Works Inc., Wilmington, California
1954-1994
Sold to Taiwan 1994
Naval Vessel Register
Inflict
456
Wilmington Boat Works Inc., Wilmington, California
1954-1990
Sold for scrap 1992
Naval Vessel Register
Loyalty
457
Wilmington Boat Works Inc., Wilmington, California
1954-1972
Sold for scrap 1973
Naval Vessel Register
Lucid
458
Higgins Corp ., New Orleans, Louisiana
1955-1970
Sold for scrap 1976 Currently being restored by the Stockton Historical Maritime Museum as a museum ship
Naval Vessel Register
Nimble
459
Higgins Corp ., New Orleans, Louisiana
1955-1970
Sold for scrap 1981
Naval Vessel Register
Notable
460
Higgins Corp ., New Orleans, Louisiana
1955-1970
Sold for scrap 1971
Naval Vessel Register
Observer
461
Higgins Corp ., New Orleans, Louisiana
1955-1972
Sold for scrap 1979
Naval Vessel Register
Pinnacle
462
Higgins Corp ., New Orleans, Louisiana
1955-1970
Sold for scrap 1978
Naval Vessel Register
Pivot
463
Wilmington Boat Works Inc., Wilmington, California
1954-1971
Initially loaned then sold to Spain as Guadalmedina M42, 1974. Decommissioned by Spain 2001.
Naval Vessel Register
Pluck
464
Wilmington Boat Works Inc., Wilmington, California
1954-1990
Sold for scrap 1992
Naval Vessel Register
Prestige
465
Wilmington Boat Works Inc., Wilmington, California
1954-1958
Grounded and sunk, 1958 in the Naruto Strait
Prime
466
Wilmington Boat Works Inc., Wilmington, California
1954-1970
Sold for scrap 1976
Naval Vessel Register
Reaper
467
Wilmington Boat Works Inc., Wilmington, California
1954-1972
Sold for scrap 1976
Naval Vessel Register
Rival
468
Luders Marine Construction Co. of Stamford, Connecticut
1954-1970
Sold for scrap 1971
Naval Vessel Register
Sagacity
469
Luders Marine Construction Co. of Stamford, Connecticut
1955-1970
Grounded at Charleston Harbor then sold for scrap 1970.
Salute
470
Luders Marine Construction Co. of Stamford, Connecticut
1955-1970
Sold for scrap 1971
Naval Vessel Register
Skill
471
Luders Marine Construction Co. of Stamford, Connecticut
1950-1970
Sold for scrap 1979, scrapped 1983.
Naval Vessel Register
Valor
472
Burger Boat Company, Manitowoc, Wisconsin
1954-1970
Sold for scrap 1971
Naval Vessel Register
Vigor
473
Burger Boat Company, Manitowoc, Wisconsin
1954-1972
Sold to Spain as Guadiana M44, 1972. Scrapped by Spain after 1999.
Naval Vessel Register
Vital
474
Burger Boat Company, Manitowoc, Wisconsin
1955-1972
Sold for scrap 1979
Naval Vessel Register
475 - 487 built for France, Portugal, Spain, Belgium and the Netherlands, not necessarily Aggressive -class ships.
Conquest
488
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1955-1970 1971-1994
Sold to Taiwan 1994 and decommissioned in 2020.
Naval Vessel Register
Gallant
489
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1955-1994
Sold to Taiwan 1994 and decommissioned in 2013.
Naval Vessel Register
Leader
490
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1955-1970 1971-1991/92
Sold for scrap 1994
Naval Vessel Register
Persistent
491
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1956-1971
Initially loaned in 1971 then sold to Spain as Guadalquivir M43
Naval Vessel Register
Pledge [5]
492
J. M. Martinac Shipbuilding Corp., Tacoma, Washington
1956-1994
Sold to Taiwan 1994 and decommissioned 2021.
Naval Vessel Register
Stalwart
493
Broward Marine Inc, Fort Lauderdale, Florida
1956-1966
Caught fire pier side at San Juan, Puerto Rico, sunk 1966. Later raised and sunk as an artificial reef.
Sturdy
494
Broward Marine Inc, Fort Lauderdale, Florida
1957-1971
Sold for scrap 1978
Naval Vessel Register
Swerve
495
Broward Marine Inc, Fort Lauderdale, Florida
1957-1971
Sold for scrap 1978
Naval Vessel Register
Venture [6]
496
Broward Marine Inc, Fort Lauderdale, Florida
1958-1971
Sold for scrap 1978
MSO-497
497
Cancelled, never built
See also
References
External links