New Mexico 1918
| No | Name | Builder | Laid down | Launched | Comm | Fate |
| BB40 | New Mexico | New York N Yd, Brooklyn | 14/10/1915 | 23/4/1917 | 20/5/1918 | stricken 2/1947 |
| BB41 | Mississippi | Newport News | 5/4/1915 | 25/1/1917 | 18/12/1917 | gunnery test ship AG128 2/1946, stricken 7/1956 |
| BB42 | Idaho | New York SB, Camden | 20/1/1915 | 30/6/1917 | 24/3/1919 | stricken 11/1947 |
|
Displacement normal, t |
32000 |
|
Displacement full, t |
33000 |
|
Length, m |
182.9 wl 190.2 oa |
|
Breadth, m |
29.7 |
|
Draught, m |
9.10 |
|
No of shafts |
4 |
|
Machinery |
BB40: electric motors, 2 General Electric (Curtis) turbo-generators, 9 Babcock & Wilcox boilers BB41: Curtis steam turbines, 9 Babcock & Wilcox boilers BB42: Parsons steam turbines, 9 Babcock & Wilcox boilers |
|
Power, h. p. |
BB40: 27500 BB41, 42: 32000 |
|
Max speed, kts |
21 |
|
Fuel, t |
oil 3270 |
|
Armour, mm |
belt: 343 - 203, bulkheads: 343 - 203, deck: 89, 63 over steering gear, barbettes: 320, turrets: 457 face, 254 - 229 sides, 229 rear, 127 crowns, CT: 406 sides, 127 roof |
|
Armament |
BB41: 4 x 3 - 356/50 Mk 4/6, 22 x 1 - 127/51 Mk 7/8/9/14/15, 4 x 1 - 76/50 Mk 10/17/18/20/21, 2 - 533 TT (beam) BB40, 42: 4 x 3 - 356/50 Mk 4/6, 14 x 1 - 127/51 Mk 7/8/9/14/15, 4 x 1 - 76/50 Mk 10/17/18/20/21, 2 - 533 TT (beam) |
|
Complement |
1084 |
Ship project history: Three battleships of this class were built under 1915 program. Designing was started in the spring of 1913, it was originally supposed to arm they with newest 406/45mm guns in twin turrets and 152mm secondary artillery, however in mid-year the decision to return to 356mm guns which at existing distances (limited to visibility conditions) practically did not yield 406mm ones in armour penetration, but had notable bigger rate of fire. Ultimately project was approved in January, 1914 when the Secretary of Navy has ordered to build new ships as Pennsylvania class. Already after the project statement in July, 1914 ship armament have strengthened, having changed 356/45mm guns by more powerful 356/50mms. Then the stem form, instead of ram, become curved (clipper bow), with the big frames slopes that has notably improved seaworthiness. Thickness of transverse bulkheads (from 320 to 343mm) and main deck (from 76 to 89mm) were raised. Besides, one of ships of the class, ÂÂ40, have decided to equip her with an experimental turbo-electric machinery.
Ship protection: 125m belt had 5.2m height and was 343mm thick at upper part tapering to 203mm at lower edge. Belt was connected with end barbettes by 343mm bulkheads. There was 2.6m in height 203mm belt at 18.3m length aft from aft bulkhead, protecting steering gear, it was closed aft by 343mm bulkhead. Flat main armour deck was connected with upper edge of belt and was 89mm over citadel. One level lower was 38mm splinter deck with 51mm slopes, slopes were connected with lower edge of belt. This deck was 63mm thick aft from citadel, protecting steering gear. Main gun turrets had 457mm faces, 254-229mm sides, 229mm rears and 127mm crowns. Barbettes were 320mm over and 114mm under main deck. CT had 406mm sides and 127mm roof. Underwater protection was 5.4m deep. There was 76mm longitudinal bulkhead.
Modernizations: 1922, all: - 2 x 1 - 127/51; + 4 x 1 - 76/50 Mk 10/17/18/20/21
1924 - 1925, New Mexico, Idaho: + 1 catapult, 1 seaplane (MO, UO, VE or OL)
1924 - 1925, Mississippi: + 2 catapults, 3 seaplanes (MO, UO, VE or OL)
(3/1931 - 1/1933, Philadelphia NYd) New Mexico, (3/1931 - 8/1932, Norfolk NYd) Mississippi, (9/1931 - 10/1934, Norfolk NYd) Idaho were modernized as follows. New machinery and boilers were fitted, horizontal armour was strengthened. Maximal main guns elevation angle was increased up to 30°.
New Mexico 1940
Mississippi 1945
|
Displacement standard, t |
33420 |
|
Displacement full, t |
36157 |
|
Length, m |
182.9 wl 190.2 oa |
|
Breadth, m |
32.4 |
|
Draught, m |
9.44 full load |
|
No of shafts |
4 |
|
Machinery |
BB40: Westinghouse geared steam turbines, 4 White Forster boilers BB41, 42: Westinghouse geared steam turbines, 6 Bureau Express boilers |
|
Power, h. p. |
40000 |
|
Max speed, kts |
22 |
|
Fuel, t |
oil 5402 (max 7053) |
|
Endurance, nm(kts) |
22000(10) - 26000(10) |
|
Armour, mm |
belt: 343 - 203, bulkheads: 343 - 203, deck: 140, splinter deck: 70, barbettes: 32, turrets: 457 face, 229 sides, 127 rear, 127 crowns, CT: 406 sides, 127 roof |
|
Armament |
4 x 3 - 356/50 Mk 7/11, 12 x 1 - 127/51 Mk 7/8/9/14/15, 8 x 1 - 127/25 Mk 10/11/13, 2 catapults, 3 seaplanes (O2U, O3U) |
|
Complement |
1443 |
Ship protection after modernization: 125m belt had 5.2m height and was 343mm thick at upper part tapering to 203mm at lower edge. Belt was connected with end barbettes by 343mm bulkheads. There was 2.6m in height 203mm belt at 18.3m length aft from aft bulkhead, protecting steering gear, it was closed aft by 343mm bulkhead. Flat main armour deck was connected with upper edge of belt and was 140mm over citadel. One level lower was 70mm splinter deck with 51mm slopes, slopes were connected with lower edge of belt. This deck was 63mm thick aft from citadel, protecting steering gear. Main gun turrets had 457mm faces, 254-229mm sides, 229mm rears and 127mm crowns. Barbettes were 320mm over and 114mm under main deck. CT had 406mm sides and 127mm roof. Underwater protection was 6.7m deep. There was 76mm longitudinal bulkhead.
Modernizations: mid-1941, all: - 2 x 1 - 127/51; + 4 x 1 - 76/50 Mk 10/17/18/20/21, (8 - 10) x 1 - 12.7/90
12/1941 - 1/1942, all: - 4 x 1 - 76/50, (4 - 6) x 1 - 12.7/90; + 4 x 4 - 28/75 Mk 1, 8 x 1 - 20/70 Oerlikon, SC, Mk 3 radars
11/1942, New Mexico, Mississippi: - 4 x 1 - 127/51, 4 x 1 - 12.7/90, 1 catapult; + 2 x 4 - 40/56 Bofors, 6 x 1 - 20/70 Oerlikon, SG radar
12/1942, Idaho: - 10 x 1 - 127/51, 4 x 4 - 28/75, 4 x 1 - 12.7/90, 1 catapult; + 10 x 4 - 40/56 Bofors, 16 x 1 - 20/70 Oerlikon
2/1943, Idaho: + 19 x 1 - 20/70 Oerlikon
10/1943, New Mexico: - 4 x 4 - 28/75, SC radar; + 2 x 4 - 40/56 Bofors, 2 x 2 - 40/56 Bofors, 10 x 1 - 20/70 Oerlikon, Mk3 (second), SG (second), SK radars
10/1943, Mississippi: - 4 x 4 - 28/75, SC radar; + 2 x 4 - 40/56 Bofors, 2 x 2 - 40/56 Bofors, 15 x 1 - 20/70 Oerlikon, Mk3 (second), SG (second), SK radars
1/1944, New Mexico: + 19 x 1 - 20/70 Oerlikon
1/1944, Mississippi: + 21 x 1 - 20/70 Oerlikon
late 1944, New Mexico, Mississippi: - Mk 3 radar; + 6 x 4 - 40/56 Bofors, Mk 8, Mk 27, 2 x Mk 28 radars
1/1945, Idaho: - 8 x 1 - 127/25, Mk 3 radar; + 10 x 1 - 127/38 Mk 12, Mk 8, Mk 27, 2 x Mk 28 radars
4/1945, Mississippi: CT was replaced by lighter with 38-mm armour; - 6 x 1 - 127/51, 10 x 1 - 20/70; + 8 x 1 - 127/25 Mk 10/11/13, 2 x 4 - 40/56 Bofors
mid-1945, Mississippi: - 6 x 1 - 20/70; + 1 x 4 - 40/56 Bofors
Naval service: New Mexico 6/1/1945 was damaged by kamikaze and repaired till March, 1945; 12/5/1945 she was badly damaged by kamikaze and repaired till August, 1945. Mississippi 9/1/1945 was damaged by kamikaze and repaired in March-April, 1945; 5/6/1945 she was again damaged by kamikaze and repaired within a month.
New Mexico 1920s
New Mexico 1945
© Ivan Gogin, 2008-10