WesWorld

New airdefence cruiser, a cousin of the RN Dido and US Atlantas.

Ajax, Sweden Cruiser laid down 1938

Displacement:
6 776 t light; 6 992 t standard; 7 500 t normal; 7 876 t full load
Loading submergence 474 tons/feet

Dimensions:
524,93 ft x 49,21 ft x 19,69 ft (normal load)
160,00 m x 15,00 m x 6,00 m

Armament:
16 - 4,13" / 105 mm guns (8 Main turrets x 2 guns, 4 superfiring turrets)
14 - 2,95" / 75 mm guns (7 2nd turrets x 2 guns)
20 - 1,57" / 40 mm AA guns
20 - 0,98" / 25 mm guns
Weight of broadside 794 lbs / 360 kg

Armour:
Belt 1,97" / 50 mm, ends unarmoured
Belts cover 145 % of normal area
Main turrets 1,18" / 30 mm, 2nd turrets 0,39" / 10 mm
Armour deck 1,18" / 30 mm, Conning tower 1,97" / 50 mm

Machinery:
Diesel Internal combustion motors,
Direct drive, 3 shafts, 107 941 shp / 80 524 Kw = 35,00 kts
Range 5 000nm at 15,00 kts

Complement:
402 - 523

Cost:
£4,139 million / $16,555 million

Distribution of weights at normal displacement:
Armament: 99 tons, 1,3 %
Armour: 870 tons, 11,6 %
Belts: 334 tons, 4,5 %, Armament: 158 tons, 2,1 %, Armour Deck: 362 tons, 4,8 %
Conning Tower: 16 tons, 0,2 %, Torpedo bulkhead: 0 tons, 0,0 %
Machinery: 2 956 tons, 39,4 %
Hull, fittings & equipment: 2 801 tons, 37,3 %
Fuel, ammunition & stores: 724 tons, 9,7 %
Miscellaneous weights: 50 tons, 0,7 %

Metacentric height 2,5

Remarks:
Hull space for machinery, storage & compartmentation is cramped
Room for accommodation & workspaces is excellent

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1,22
Shellfire needed to sink: 5 025 lbs / 2 279 Kg = 142,3 x 4,1 " / 105 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0,8
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 50 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0,37
Relative quality as seaboat: 1,10

Hull form characteristics:
Block coefficient: 0,516
Sharpness coefficient: 0,33
Hull speed coefficient 'M': 8,20
'Natural speed' for length: 22,91 kts
Power going to wave formation at top speed: 64 %
Trim: 45
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 138,6 %
Relative accommodation and working space: 165,0 %
(Average = 100%)
Displacement factor: 98 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0,94
(Structure weight / hull surface area: 90 lbs / square foot or 441 Kg / square metre)
Relative longitudinal hull strength: 1,70
(for 21,00 ft / 6,40 m average freeboard, freeboard adjustment 6,70 ft)
Relative composite hull strength: 1,00

While I like the idea of an 10,2cm armed AA cruiser I think you´ll face problems with topweight on such a long and slender hull with all those superfiring guns assume the bridge will be even higher as will all the FC equipement.

I would also cut her speed. You can´t outrun airplanes anyway.

I agree with Hoo, she has in my opinion way too many guns for that slim hull, and more speed than nessassary.

And I won't even go into the issues with diesels ;-) I'd try 4.5" as a calibre and sligtly less guns?

cheers

Bernhard

Why is there an CT on a vessel like that? Isn´t this just a waste of weight?

How to arrange all those guns to allow useful fire arcs? The main guns may be grouped like on ATLANTA but where to put all the other stuff?

Glad she has no TTs that would eat up even more space..

I´ve modified her a little bit. Playing around with her dimensions (l:b ratio below 9:1 now) and by dropping her speed by 1,5kn I got a design that seems more "balanced"....

Please let me note that I´ve doubts a small navy can affort a ship like that - they need multi-role cruisers instead.

Cheers,

HoOmAn

PS: Spring* rates her as having "Roomy upper decks; superior accommodation and working space"!!! *lol*

AA Ajax, laid down 1938

Length, 160.0 m x Beam, 18.0 m x Depth, 5.2 m
7550 tonnes normal displacement (6833 tonnes standard)

Main battery: 16 x 10.5-cm (8 x 2; 4 superfiring)
Secondary battery: 14 x 7.5-cm
AA battery: 20 x 4.0-cm
Light battery: 20 x 2.0-cm

Weight of broadside: 359 kg

Main belt, 5.0 cm; ends unarmored
Armor deck, average 3.0 cm
Conning tower, 5.0 cm

Battery armor:
Main, 3.0 cm / secondary, 1.0 cm shields


Maximum speed for 68958 shaft kw = 33.50 knots
Approximate cruising radius, 7000 nm / 15 knots

Typical complement: 405-526


Estimated cost, $15.075 million (£3.769 million)

Remarks:

Relative extent of belt armor, 121 percent of 'typical' coverage.

Ship has slow, easy roll; a good, steady gun platform.

Magazines and engineering spaces are cramped, with poor
watertight subdivision.

Roomy upper decks; superior accommodation and working space.


Distribution of weights:
Percent
normal
displacement:

Armament ......................... 99 tonnes = 1 pct
Armor, total ..................... 893 tonnes = 12 pct

Belt 311 tonnes = 4 pct
Deck 426 tonnes = 6 pct
C.T. 16 tonnes = 0 pct
Armament 140 tonnes = 2 pct

Machinery ........................ 2530 tonnes = 34 pct
Hull and fittings; equipment ..... 3044 tonnes = 40 pct
Fuel, ammunition, stores ......... 933 tonnes = 12 pct
Miscellaneous weights ............ 50 tonnes = 1 pct
-----
7550 tonnes = 100 pct

Estimated metacentric height, 0.9 m

Displacement summary:

Light ship: 6616 tonnes
Standard displacement: 6833 tonnes
Normal service: 7550 tonnes
Full load: 8093 tonnes

Loading submergence 1825 tonnes/metre

+++++++++++++++++++++++++


Estimated overall survivability and seakeeping ability:

Relative margin of stability: 1.12

Shellfire needed to sink: 3233 kg = 201.4 x 10.5-cm shells
(Approximates weight of penetrating
shell hits needed to sink ship,
not counting critical hits)

Torpedoes needed to sink: 1.1
(Approximates number of 'typical'
torpedo hits needed to sink ship)

Relative steadiness as gun platform, 70 percent
(50 percent is 'average')

Relative rocking effect from firing to beam, 0.27

Relative quality as a seaboat: 1.00

+++++++++++++++++++++++++


Hull form characteristics:

Block coefficient: 0.50
Sharpness coefficient: 0.34
Hull speed coefficient 'M' = 8.18
'Natural speed' for length = 22.9 knots
Power going to wave formation
at top speed: 63 percent


Estimated hull characteristics and strength:

Relative underwater volume absorbed by
magazines and engineering spaces: 120 percent

Relative accommodation and working space: 192 percent


Displacement factor: 111 percent
(Displacement relative to loading factors)


Relative cross-sectional hull strength: 0.95
(Structure weight per square
metre of hull surface: 463 kg)

Relative longitudinal hull strength: 1.64
(for 6.40 m average freeboard;
freeboard adjustment +2.04 m)

Relative composite hull strength: 1.00

+++++++++++++++++++++++++


[Machine-readable parameters: Spring Style v. 1.2.1]

524.80 x 59.04 x 17.06; 20.99 -- Dimensions
0.50 -- Block coefficient
1938 -- Year laid down
33.50 / 7000 / 15.00; Oil-fired turbine or equivalent -- Speed / radius / cruise
50 tons -- Miscellaneous weights
++++++++++
16 x 4.13; 8; 4 -- Main battery; turrets; superfiring
:
14 x 2.95; 0 -- Secondary battery; turrets
Gun-shields
:
20 x 1.57 -- Tertiary (QF/AA) battery
:
20 x 0.79 -- Fourth (light) battery
0 -- No torpedo armament
++++++++++
1.97 / 0.00 / 0.00 / 0.00; 121 -- Belt armor; relative extent
1.18 / 1.97 -- Deck / CT
1.18 / 0.39 / 0.00 / 0.00 -- Battery armor


(Note: For portability, values are stored in Anglo-American units)


+++++++++++++++++++++++++++++++++++++++++++++++++++++++

Instead of building a completely new ship, how about rebuilding the Admiral Class cruisers? New machinery getting the speed up to 30knts. Fit her with new guns. probably 12x105mm in 6 turrets will fit. A sprinkling of light AAA around the upperworks.

"A sprinkling of light AAA around the upperworks."

Hee hee sounds like your baking a cake Gavin...

However, I neglected to include cooking instructions.

She is redesigned, longer and wider with less speed but with more armour and higher crusingspeed.

Ajax, Sweden Cruiser laid down 1940

Ajax, Sweden Cruiser laid down 1940

Displacement:
7 436 t light; 7 682 t standard; 9 000 t normal; 10 019 t full load
Loading submergence 580 tons/feet

Dimensions:
557,74 ft x 59,06 ft x 19,69 ft (normal load)
170,00 m x 18,00 m x 6,00 m

Armament:
16 - 4,13" / 105 mm guns (8 Main turrets x 2 guns, 2 superfiring turrets)
14 - 2,95" / 75 mm guns
20 - 1,57" / 40 mm AA guns
20 - 0,98" / 25 mm guns
Weight of broadside 794 lbs / 360 kg

Armour:
Belt 2,76" / 70 mm, ends unarmoured
Belts cover 125 % of normal area
Main turrets 1,97" / 50 mm, 2nd turrets 10,00" / 254 mm
AA gun shields 0,20" / 5 mm, Light gun shields 0,20" / 5 mm
Armour deck 1,97" / 50 mm, Conning tower 1,57" / 40 mm

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 3 shafts, 92 224 shp / 68 799 Kw = 33,00 kts
Range 6 000nm at 20,00 kts

Complement:
462 - 600

Cost:
£4,133 million / $16,532 million

Distribution of weights at normal displacement:
Armament: 99 tons, 1,1 %
Armour: 1 469 tons, 16,3 %
Belts: 475 tons, 5,3 %, Armament: 240 tons, 2,7 %, Armour Deck: 740 tons, 8,2 %
Conning Tower: 15 tons, 0,2 %, Torpedo bulkhead: 0 tons, 0,0 %
Machinery: 2 466 tons, 27,4 %
Hull, fittings & equipment: 3 352 tons, 37,2 %
Fuel, ammunition & stores: 1 564 tons, 17,4 %
Miscellaneous weights: 50 tons, 0,6 %

Metacentric height 3,7

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is excellent

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1,33
Shellfire needed to sink: 12 495 lbs / 5 668 Kg = 353,8 x 4,1 " / 105 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 1,6
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 51 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0,19
Relative quality as seaboat: 1,18

Hull form characteristics:
Block coefficient: 0,486
Sharpness coefficient: 0,33
Hull speed coefficient 'M': 8,20
'Natural speed' for length: 23,62 kts
Power going to wave formation at top speed: 60 %
Trim: 43
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 98,5 %
Relative accommodation and working space: 178,5 %
(Average = 100%)
Displacement factor: 124 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0,95
(Structure weight / hull surface area: 95 lbs / square foot or 465 Kg / square metre)
Relative longitudinal hull strength: 1,58
(for 21,33 ft / 6,50 m average freeboard, freeboard adjustment 6,50 ft)
Relative composite hull strength: 1,00

Ajax Aegis Achilles Agamenon

I'm not sure I see the point of fourteen 3" guns backing up sixteen 4.1" guns; I'd just go with 4.1", 40 mm, and 25 mm. I doubt there's deck space for it, either, but I'd need to see a sketch first.

I assume the lay out is two turrets forward, two aft, two on either beam amidships?

Why is the belt 125% when the magazines and engineering spaces only occupy 98%?

Performance is impressive, but there might be some merit in going for a "steady gun platform" remark.

Where how high sould the value be for "A goog steady gun platform"?

Ajax, Sweden Cruiser laid down 1940

Displacement:
7 101 t light; 7 327 t standard; 8 600 t normal; 9 584 t full load
Loading submergence 563 tons/feet

Dimensions:
557,74 ft x 59,06 ft x 19,69 ft (normal load)
170,00 m x 18,00 m x 6,00 m

Armament:
16 - 4,13" / 105 mm guns (8 Main turrets x 2 guns, 2 superfiring turrets)
40 - 1,57" / 40 mm AA guns
20 - 0,98" / 25 mm guns
Weight of broadside 653 lbs / 296 kg

Armour:
Belt 2,76" / 70 mm, ends unarmoured
Belts cover 100 % of normal area
Main turrets 1,97" / 50 mm, AA gun shields 0,20" / 5 mm, Light gun shields 0,20" / 5 mm
Armour deck 1,97" / 50 mm, Conning tower 1,57" / 40 mm

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 3 shafts, 88 622 shp / 66 112 Kw = 33,00 kts
Range 6 000nm at 20,00 kts

Complement:
446 - 580

Cost:
£3,893 million / $15,571 million

Distribution of weights at normal displacement:
Armament: 82 tons, 0,9 %
Armour: 1 330 tons, 15,5 %
Belts: 380 tons, 4,4 %, Armament: 218 tons, 2,5 %, Armour Deck: 717 tons, 8,3 %
Conning Tower: 14 tons, 0,2 %, Torpedo bulkhead: 0 tons, 0,0 %
Machinery: 2 370 tons, 27,6 %
Hull, fittings & equipment: 3 250 tons, 37,8 %
Fuel, ammunition & stores: 1 499 tons, 17,4 %
Miscellaneous weights: 70 tons, 0,8 %

Metacentric height 3,7

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is excellent
Good seaboat, rides out heavy weather easily

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1,33
Shellfire needed to sink: 12 097 lbs / 5 487 Kg = 342,5 x 4,1 " / 105 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 1,6
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 53 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0,16
Relative quality as seaboat: 1,23

Hull form characteristics:
Block coefficient: 0,464
Sharpness coefficient: 0,33
Hull speed coefficient 'M': 8,32
'Natural speed' for length: 23,62 kts
Power going to wave formation at top speed: 59 %
Trim: 43
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 98,1 %
Relative accommodation and working space: 179,4 %
(Average = 100%)
Displacement factor: 127 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0,95
(Structure weight / hull surface area: 94 lbs / square foot or 459 Kg / square metre)
Relative longitudinal hull strength: 1,61
(for 21,33 ft / 6,50 m average freeboard, freeboard adjustment 6,63 ft)
Relative composite hull strength: 1,00

Ajax Aegis Achilles Agamenon

"Relative quality as seaboat: 1,23"

If you bring it up to 1,25 you should get the good seakeeping designation.

Good seaboat, rides out heavy weather easily

The border for that is 1,20, is steady gun platform decided by stability or seakeeping, (stability 1,33, seakeaping 1,23)?

Normally you would adjust the trim until you reach a steadiness of 70 to get the "steady gun platform" rating.
To get the "steady gun platform" without adjusting the trim, you need the seakeeping at about 1.40 to get the steadiness to 70.

In that case you get:

Ajax, Sweden Cruiser laid down 1940

Displacement:
7,101 t light; 7,327 t standard; 8,600 t normal; 9,584 t full load
Loading submergence 563 tons/feet

Dimensions:
557.74 ft x 59.06 ft x 19.69 ft (normal load)
170.00 m x 18.00 m x 6.00 m

Armament:
16 - 4.13" / 105 mm guns (8 Main turrets x 2 guns, 2 superfiring turrets)
40 - 1.57" / 40 mm AA guns
20 - 0.98" / 25 mm guns
Weight of broadside 653 lbs / 296 kg

Armour:
Belt 2.76" / 70 mm, ends unarmoured
Belts cover 100 % of normal area
Main turrets 1.97" / 50 mm, AA gun shields 0.20" / 5 mm, Light gun shields 0.20" / 5 mm
Armour deck 1.97" / 50 mm, Conning tower 1.57" / 40 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 78,151 shp / 58,301 Kw = 32.00 kts
Range 6,000nm at 20.00 kts

Complement:
446 - 580

Cost:
£3.658 million / $14.631 million

Distribution of weights at normal displacement:
Armament: 82 tons, 0.9 %
Armour: 1,333 tons, 15.5 %
Belts: 380 tons, 4.4 %, Armament: 222 tons, 2.6 %, Armour Deck: 717 tons, 8.3 %
Conning Tower: 14 tons, 0.2 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 2,090 tons, 24.3 %
Hull, fittings & equipment: 3,526 tons, 41.0 %
Fuel, ammunition & stores: 1,499 tons, 17.4 %
Miscellaneous weights: 70 tons, 0.8 %

Metacentric height 3.3

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.22
Shellfire needed to sink: 13,207 lbs / 5,991 Kg = 373.9 x 4.1 " / 105 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 1.8
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 70 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.20
Relative quality as seaboat: 1.39

Hull form characteristics:
Block coefficient: 0.464
Sharpness coefficient: 0.33
Hull speed coefficient 'M': 8.32
'Natural speed' for length: 23.62 kts
Power going to wave formation at top speed: 57 %
Trim: 50
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 87.7 %
Relative accommodation and working space: 184.9 %
(Average = 100%)
Displacement factor: 138 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 1.02
(Structure weight / hull surface area: 101 lbs / square foot or 493 Kg / square metre)
Relative longitudinal hull strength: 1.82
(for 21.98 ft / 6.70 m average freeboard, freeboard adjustment 7.29 ft)
Relative composite hull strength: 1.08


Walter

There is a picture avalible at:

http://www.geocities.com/kustflottan/kfl...mp/newships.htm