NAVYPEDIA

Photo

Embattle 1963

Ships

No	Name	Yard No	Builder	Laid down	Launched	Comm	Fate
MSO421	Agile		Luders Marine, Stamford	2.1954	19.11.1955	6.1956	stricken 9.1977
AM422, 2.1955- MSO422	Aggressive		Luders Marine, Stamford	5.1951	4.10.1952	11.1953	stricken 2.1975
AM423, 1.1955- MSO423	Avenge		Luders Marine, Stamford	8.1951	15.3.1953	5.1954	stricken 2.1970
AM424, 2.1955- MSO424	Bold		Norfolk N Yd, Portsmouth	12.1951	14.3.1953	9.1953	stricken 2.1975
AM425, 2.1955- MSO425	Bulwark		Norfolk N Yd, Portsmouth	12.1951	14.3.1952	11.1953	stricken 2.1975
AM426, 2.1955- MSO426	Conflict		Fulton, Antioch	8.1951	16.12.1952	3.1954	stricken 6.1972
AM427, 2.1955- MSO427	Constant		Fulton, Antioch	8.1951	14.2.1953	9.1954	stricken 3.1994
AM428, 2.1955- MSO428	Dash		Astoria Marine	7.1951	20.9.1952	8.1953	sold 1.1984
AM429, 2.1955- MSO429	Detector		Astoria Marine	10.1951	5.12.1952	1.1953	stricken 12.1983
AM430, 2.1955- MSO430	Direct		Hiltebrant, Kingston	2.1952	27.5.1953	7.1954	stricken 10.1982
AM431, 2.1955- MSO431	Dominant		Hiltebrant, Kingston	4.1952	5.11.1953	11.1954	sold 1.1984
AM432, 2.1955- MSO432	Dynamic		Colberg, Stockton	10.1951	17.12.1952	12.1953	to Spain 7.1971 (Guadalete)
AM433, 2.1955- MSO433	Engage		Colberg, Stockton	11.1951	18.6.1953	6.1954	stricken 4.1992
AM434, 2.1955- MSO434	Embattle		Colberg, Stockton	11.1951	27.8.1953	11.1954	stricken 5.1976
AM435, 2.1955- MSO435	Endurance		Martinac, Tacoma	1.1952	8.8.1952	5.1954	stricken 7.1972
AM436, 2.1955- MSO436	Energy		Martinac, Tacoma	3.1952	13.2.1953	7.1954	to Philippines 7.1972 (Davao del Norte)
MSO437	Enhance		Maritinolich, San Diego	7.1952	11.10.1952	4.1955	stricken 2.1992
MSO438	Esteem		Maritinolich, San Diego	9.1952	20.12.1952	9.1955	stricken 9.1991
MSO439	Excel		Higgins, New Orleans	2.1953	25.9.1953	2.1955	stricken 3.1994
AM440, 2.1955- MSO440	Exploit		Higgins, New Orleans	12.1951	10.4.1953	3.1954	stricken 3.1994
AM441, 2.1955- MSO441	Exultant		Higgins, New Orleans	5.1952	6.6.1953	3.1954	stricken 3.1994
AM442, 2.1955- MSO442	Fearless		Higgins, New Orleans	7.1952	17.7.1953	9.1954	stricken 10.1990
AM443, 2.1955- MSO443	Fidelity		Higgins, New Orleans	12.1952	21.8.1953	1.1955	stricken 6.1989
AM444, 2.1955- MSO444	Firm		Martinac, Tacoma	4.1952	15.4.1953	10.1954	to Philippines 7.1972 (Davao del Sur)
AM445, 2.1955- MSO445	Force		Martinac, Tacoma	8.1952	26.6.1953	1.1955	fire 24.4.1973
AM446, 2.1955- MSO446	Fortify		Seattle SB	11.1951	19.2.1953	7.1954	stricken 3.1994
MSO447	Guide		Seattle SB	2.1953	17.4.1954	3.1955	stricken 7.1972
AM448, 2.1955- MSO448	Illusive		Martinolich, San Diego	10.1951	12.7.1952	11.1953	stricken 6.1990
AM449, 2.1955- MSO449	Impervious		Martinolich, San Diego	11.1951	29.8.1952	7.1954	stricken 3.1992
AM455, 2.1955- MSO455	Implicit		Wilmington BW	10.1952	1.8.1953	3.1954	to Taiwan 9.1994 (永陽 [Yung Yang])
AM456, 2.1955- MSO456	Inflict		Wilmington BW	10.1952	16.10.1953	5.1954	stricken 5.1990
AM457, 2.1955- MSO457	Loyalty		Wilmington BW	11.1951	22.11.1953	6.1954	stricken 7.1972
MSO458	Lucid		Higgins, New Orleans	3.1953	14.11.1953	5.1955	stricken 5.1976
MSO459	Nimble		Higgins, New Orleans	4.1953	6.8.1954	5.1955	stricken 11.1976
MSO460	Notable		Higgins, New Orleans	6.1953	15.10.1954	6.1955	stricken 2.1971
MSO461	Observer		Higgins, New Orleans	7.1953	19.10.1954	8.1955	stricken 9.1977
MSO462	Pinnacle		Higgins, New Orleans	8.1953	3.1.1955	10.1955	stricken 11.1977
AM463, 2.1955- MSO463	Pivot		Wilmington BW	3.1952	9.1.1954	7.1954	to Spain 7.1971 (Guadalmedina)
AM464, 2.1955- MSO464	Pluck		Wilmington BW	3.1952	6.2.1954	8.1954	stricken 1.1991
AM465, 2.1955- MSO465	Prestige		Wilmington BW	4.1952	30.4.1954	9.1954	wrecked 23.8.1958
AM466, 2.1955- MSO466	Prime		Wilmington BW	12.1952	27.5.1954	10.1954	stricken 10.1976
AM467, 2.1955- MSO467	Reaper		Wilmington BW	5.1952	25.6.1954	11.1954	stricken 2.1975
AM468, 2.1955- MSO468	Rival		Luders Marine, Stamford	2.1952	15.8.1953	9.1954	stricken 2.1971
AM469, 2.1955- MSO469	Sagacity		Luders Marine, Stamford	10.1952	26.2.1954	1.1955	stricken 10.1970
MSO470	Salute		Luders Marine, Stamford	3.1953	14.8.1954	5.1955	stricken 2.1971
MSO471	Skill		Luders Marine, Stamford	8.1953	3.4.1955	11.1955	stricken 9.1977
AM472, 2.1955- MSO472	Valor		Burger Boat, Manitowoc	4.1952	13.5.1953	7.1954	stricken 2.1971
AM473, 2.1955- MSO473	Vigor		Burger Boat, Manitowoc	6.1952	23.6.1953	11.1954	to Spain 4.1972 (Guadiana)
MSO474	Vital		Burger Boat, Manitowoc	10.1952	12.8.1953	6.1955	stricken 9.1977
MSO488	Conquest		Martinac, Tacoma	3.1953	20.5.1954	7.1955	stricken 6.1994, to Taiwan (永慈 [Yung Tzu])
MSO489	Gallant		Martinac, Tacoma	5.1953	4.6.1954	9.1955	stricken 4.1994, to Taiwan (永固 [Yung Ku])
MSO490	Leader		Martinac, Tacoma	9.1953	15.9.1954	11.1955	stricken 3.1992
MSO491	Persistent		Martinac, Tacoma	6.1954	23.4.1955	2.1956	to Spain 7.1971 (Guadalquivir)
MSO492	Pledge		Martinac, Tacoma	6.1954	20.7.1955	4.1956	stricken 1.1994, to Taiwan (永德 [Yung Teh])
MSO493	Stalwart		Boward Marine, Fort Lauderdale	6.1954	3.12.1955	4.1957	fire 25.6.1966
MSO494	Sturdy		Boward Marine, Fort Lauderdale	10.1954	28.1.1956	10.1957	stricken 9.1977
MSO495	Swerve		Boward Marine, Fort Lauderdale	12.1954	1.11.1955	7.1957	sold 2.1978
MSO496	Venture		Boward Marine, Fort Lauderdale	1.1955	27.11.1956	2.1958	stricken 9.1977
MSO508	Acme		Frank Sample, Boothbay Harbor	11.1954	23.6.1955	3.1957	stricken 5.1976
MSO509	Adroit		Frank Sample, Boothbay Harbor	11.1954	20.8.1955	3.1957	stricken 5.1992
MSO510	Advance		Frank Sample, Boothbay Harbor	6.1955	12.7.1956	6.1958	stricken 5.1976
MSO511	Affray		Frank Sample, Boothbay Harbor	8.1955	18.12.1956	12.1958	stricken 6.1993

Technical data

Displacement standard, t	637
Displacement full, t	735
Length, m	50.3 wl 52.3 oa
Breadth, m	10.4
Draught, m	4.00
No of shafts	2
Machinery	MSO421 - 427, 432 - 449, 455 - 474, 488 - 496, 508 - 511: 4 Packard diesels MSO428 - 431: 2 General Motors diesels
Power, h. p.	MSO421: 3040 MSO422 - 427, 432 - 449, 455 - 474, 488 - 496, 508 - 511: 2280 MSO428 - 431: 1520
Max speed, kts	MSO421: 15 MSO422 - 427, 432 - 449, 455 - 474, 488 - 496, 508 - 511: 14 MSO428 - 431: 13
Fuel, t	diesel oil
Endurance, nm(kts)	2400(12)
Armament	1 x 1 - 40/60 Mk 3, 2 x 1 - 12.7/90, A Mk 2, A Mk 4, A Mk 6 acoustic, M Mk 5, M Mk 6, M Mk 7 magnetic, Oropesa No.1 wire minesweeping gear
Electronic equipment	SPS-53 radar, UQS-1 sonar
Complement	70

Graphics

Project history

Although minesweeper design continued after 1945, and although the prototype new ocean sweeper was authorised under the FY50 programme, construction on a large scale did not begin until the Korean War, with ten units under the FY51 first supplemental budget, eighteen under the second, and fifteen under die third, another five being planned under the FY52 programme. The new sweeper was somewhat smaller than the 180ft Second World War type, and it was built of plywood for minimum magnetic signature. Two XMAP pressure sweeping caissons could be towed. Given problems in diesel engine procurement under what were then expected to be mobilisation conditions, designs were prepared for either a new Packard light-weight engine or for an existing GM commercial type. Reportedly the rapid development of the Packard (which was also used in the new coastal sweepers) and its aircraft-type design led to many mechanical problems, which were not corrected for as much as eight years after us introduction. Given its unfortunate reputation, the Packard never saw large-scale commercial service, and the Navy suffered again as production ended and spares were largely unavailable. Of ninety-three ships to the SCB-45A or Agile class design, fifty-eight were retained by the US Navy, the others being transferred.

The Acme (MSO508) and Ability (MSO519) classes were improved and slightly enlarged Agiles built under the FY54 and 55 programme, the latter designed as mine division flagships. Ultimately both series were fitted as flagships.

All of the new ocean sweepers were built of wood with bronze and stainless (non-magnetic) steel fittings, with automatic degaussing, to compensate for course changes, as well as electrical insulators in internal piping, lifelines, and stays. All also had a new mine-locating sonar, UQS-1, later replaced by SQQ-14, a variable-depth unit on a rigid retractable rod.

Modernizations

1969, Engage, Exultant, Fearless, Fidelity, Force, Fortify, Impervious, Inflict; 1970, Enhance, Esteem, Illusive, Conquest, Leader: main diesels were replaced by 4 Waukesha (2280hp); - 1 x 1 - 40/60, UQS-1 sonar; + SQQ-14 sonar.

Naval service

Force was lost by fire off Guam 24.4.1973. Prestige ran aground 23.8.1958 in Naruto Straits (Japanese Inland Sea) and abandoned as CTL. Stalwart was lost by fire at San Juan (Perto Rico) 25.6.1966.