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HoOmAn

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1

Saturday, June 21st 2003, 3:45pm

The other thread - a quiz!

Folks,

you´ve all discussed normal and weird designs at length at this place. I think it´s time for something different. Therefor, I´ll offer you something to proof if you learned to listen what each "designer" likes and what he´s up for in future designs. :o)

Below is a linedrawing I´ve made lately showing a ship I´ll build one fine day. What do you think it is? Furthermore I´d like to know if you can guess it´s stats using springsharp or springstyle like hullsize, armament etc.

Examine the picture, calculate the ships dimensions with help of the scale given and the knowledge, that all drawings I posted so far were of the same scale.

The only hint I´ll offer is that the design is laid down in the mid-30s. You´ll need that when fooling around with springsharp, though.

There´s nothing to win except for the honour to be the best in identifying and guessing. I´ll post its real stats once one of you gets really close. :oP

Good luck!



2

Saturday, June 21st 2003, 5:51pm

LxBxT look to be around ca. 140-150m x 13-14m x 9m. I would hazard a speed of up to 35 knots, but you may have skimped on hull-stregnth (i.e. utilising design-practise common for destroyers). Armament looks to be 8x13cm DP or 8x14cm DP, with 6 4cm AA (or 3.7cm) and 16 2cm AA. No TT seem apparent, but there is an aircraft present.

It is a cruiser of some sort - I'd guess around 4500-5500 tons standard displacement, and intended to combine being a flotilla-leader for destroyers and being a trade-protection cruiser. It doesn't look to have much space assigned to mines, so I don't think it's a minecruiser. Armour seems light and patchy. Am wondering if that bow gives good sea-keeping at high speeds - my guess would be "no".

HoOmAn

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3

Saturday, June 21st 2003, 6:26pm

Nice shot...

Nice shot, Prengolodh, but still not perfectly close to the original design.

Note: I haven´t skimped on hull strength because the design is well over DD-size.

You´re right on the TTs and the main guns are of course those well known 13,3cm twins.

Parts of the rest are close except for the AA equipement even though it is difficult to judge that from the scale/resolution I choosed. You´ve missed a lot of those smaller guns.

Anybody else out there to try a shot?

4

Sunday, June 22nd 2003, 2:27am

well

without useing springstyle and looking at the scale and time laid down I'd hazzard a guess of 170/180m by 15/17m with a draft of 5/7m. As for her class she looks to be a light cruiser creeping up towards the 7000 ton range. I think shes capable of 33/35 knots and shes got quite a nice AA suite as well. I'm guessing that she mounts 6x88's (3.4") 16x1.3cm guns and 2x20mm guns forward in addition to the 5.25"/13.3cm main guns. She seems to me to be an AA cruiser with all those lighter guns and without torpedos I don't think she would be used with DD's as a leader.

HoOmAn

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5

Sunday, June 22nd 2003, 2:58am

Well done too....

You´re right, she´s meant to be an AA cruiser. Leading DDs or act as a trade protection cruiser comes second to that.

On the other hand you´re wrong about her secondaries. There are no 88s. To be precise: There´s no caliber between 13,3cm and 4cm, so no real secondaries.

Further more, she´s (much) lighter than you expect her to be. Pengs guess was - more or less - in the right range.

What strikes me is, that it doesn´t seem to be obvious that there are mounts with more than 2 barrels on her. Maybe that´s a hint for me to work on the small details, even though with a resolution where a pixel is a 40cmx40cm square you can hardly work out the difference between 2cm and 4cm...

But it´s only for fun and you guys are getting closer. :o)

6

Sunday, June 22nd 2003, 11:11am

It even looks like a Dido class cruiser. Q mount has been eliminated and the bridge lowered and brought forwards to allow for aircraft stoage. So i figure you look the Dido dimensions, cut 1ft off the beam and 20ft off the length. The proliferation of boats give the idea that it will sink easily; a cockleshell cruiser and all round dogsbody?

What program do you use Hooman?

7

Sunday, June 22nd 2003, 11:48am

40x40 ? Are you sure ?

Because if that is the case, the 0-30m scale line (at 86 pixels) is too long (should be 75 pixels long). Also if you were to use 40x40, you'll get a design of 164.4 m x 17.2 m x 6.8 m with a normal displacement of around 9,800 tons (BC=0.5).
Using the scale given on the picture , one pixel is actually 34.88 x 34.88 cm, giving you a ship that is 143.37 m x 15.00 m x 5.93 m. with a normal displacement of about 6400 tons with a BC of 0.5, which would be closer to what Pengolodh had (with a 6000-7000 NM range at 15 kts, Standard displacement would be around 5700 tons. A 10,000 NM range at 15 knots would put you under the 5,500 ton mark).

Walter

HoOmAn

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8

Sunday, June 22nd 2003, 2:25pm

Quoted

Originally posted by Red Admiral
It even looks like a Dido class cruiser. Q mount has been eliminated and the bridge lowered and brought forwards to allow for aircraft stoage. So i figure you look the Dido dimensions, cut 1ft off the beam and 20ft off the length. The proliferation of boats give the idea that it will sink easily; a cockleshell cruiser and all round dogsbody?

What program do you use Hooman?


You´re right to guess the DIDOs inspired me. Actually, it was the SPARTAN-class, a modified DIDO, which looked like it could be a good idea to have. The main difference are the planes and hangars I put on my cruiser for which I used a forward superstructur more like the SOUTHAMPTON-class light cruisers (cut away the upper two deck levels on her bridge, though, to get a low silluette). Coupled with some other ideas, that´s where the designs general look and layout came from.

As for the boats they will be given off board during wartime service but it is peace in our times so some boats are necessary. :o)

cockleshell cruiser?!

For drawing those pics I´m using Coral Paint 10 - not perfect for this task but good enough.

HoOmAn

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9

Sunday, June 22nd 2003, 2:32pm

Quoted

Originally posted by Rooijen10
Because if that is the case, the 0-30m scale line (at 86 pixels) is too long (should be 75 pixels long). Also if you were to use 40x40, you'll get a design of 164.4 m x 17.2 m x 6.8 m with a normal displacement of around 9,800 tons (BC=0.5).


Well, you´re right. 40x40 is a little bit too big but close enough for a guess. 35x35cm is much closer but not as easy for some off hand math.

Anyway, funny thing you counted the pixels! ;oP

Quoted

Using the scale given on the picture , one pixel is actually 34.88 x 34.88 cm, giving you a ship that is 143.37 m x 15.00 m x 5.93 m. with a normal displacement of about 6400 tons with a BC of 0.5, which would be closer to what Pengolodh had (with a 6000-7000 NM range at 15 kts, Standard displacement would be around 5700 tons. A 10,000 NM range at 15 knots would put you under the 5,500 ton mark).


Given the inaccuracies of the paint programm where I need an odd number of pixels for the ships beam for example (otherwise I can´t place anything on the centerline) the latter dimensions are pretty close and using a BC of 0,48 gives you the a standarddisplacement somewhat lower.

HoOmAn

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10

Sunday, June 22nd 2003, 2:49pm

You guys made it!

So finally, I present the cruisers real stats!

Some notes first:

- As said before, inspiration came from the DIDOs which I think look damn cool, especially those mounts.

- I like small and fast cruisers more than big ones what you surely have noticed from older discussions so the DIDOs fitted in that sheme too.

- I also think there is not too much armor necessary on a cruiser. Studying the fights of WW2 one gets the impression that other things like redundancy of important systems is more important. So the ship got 2 main FC plus 4 specialized AA fire directors but somewhat thin armor.

- The RSAN is too small to affort single purpose cruisers so while the design focuses on AA equipement, it should also be able to act as a fleet scout or trade protection cruiser to some degree so I thought two planes would be a good idea for which a hangar was placed abreast the forward funnel.

- Furthermore, having some overseas territories, long range was necessary.


When I simned the vessel I had in mind it turned out to be ~200ts to 500ts smaller than a DIDO- or SPARTAN-class cruiser with similar speed, slightly better armor (not thicker but covering a larger area) but much more light AA guns and 2,5 times a DIDOs range. Furthermore it was laid down three years earlier than the first DIDO.

To identify the small AA guns on the pic is somewhat difficult, I know. On the other hand I´m using the same mounts for the same guns on all my pics and if you´ve seen some on the Design Board of warships1.com or here in the news section with their stats you should have been able to get close to the original layout.

So actually, the ship features (from bow to stern)

1x2 13,3cm, 1x2 13,3cm, 2x1 2cm, 2x2 4cm, 2x6 2cm, 2x2 4cm, 2x2 4cm, 2x2 4cm, 1x6 2cm, 1x2 13,3cm, 1x2 13,3cm

for a total of 8x 13,3cm, 16x 4cm and 20x 2cm. No TTs.


Flakkreuzer 34, South African AA cruiser laid down 1934

Displacement:
5.074 t light; 5.243 t standard; 5.906 t normal; 6.413 t full load
Loading submergence 395 tons/feet

Dimensions:
475,72 ft x 47,57 ft x 19,03 ft (normal load)
145,00 m x 14,50 m x 5,80 m

Armament:
8 - 5,24" / 133 mm guns (4 Main turrets x 2 guns, 2 superfiring turrets)
16 - 1,57" / 40 mm AA guns
20 - 0,79" / 20 mm guns
Weight of broadside 610 lbs / 277 kg

Armour:
Belt 1,97" / 50 mm, ends unarmoured
Belts cover 122% of normal area
Main turrets 1,57" / 40 mm
Armour deck 1,18" / 30 mm, Conning tower 1,97" / 50 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 69.638 shp / 51.950 Kw = 32,35 kts
Range 12.000nm at 12,00 kts

Complement:
336 - 437

Cost:
£2,563 million / $10,253 million

Distribution of weights at normal displacement:
Armament: 76 tons, 1,3%
Armour: 683 tons, 11,6%
Belts: 252 tons, 4,3%, Armament: 115 tons, 1,9%, Armour Deck: 302 tons, 5,1%
Conning Tower: 14 tons, 0,2%, Torpedo bulkhead: 0 tons, 0,0%
Machinery: 2.003 tons, 33,9%
Hull, fittings & equipment: 2.236 tons, 37,9%
Fuel, ammunition & stores: 832 tons, 14,1%
Miscellaneous weights: 75 tons, 1,3%

Metacentric height 2,0

Remarks:
Hull space for machinery, storage & compartmentation is cramped
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: 1,12
Shellfire needed to sink: 4.886 lbs / 2.216 Kg = 68,1 x 5,2 " / 133 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0,9
(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: 0,40
Relative quality as seaboat: 1,20

Hull form characteristics:
Block coefficient: 0,480
Sharpness coefficient: 0,32
Hull speed coefficient 'M': 8,05
'Natural speed' for length: 21,81 kts
Power going to wave formation at top speed: 62 %
Trim: 58
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 121,4%
Relative accommodation and working space: 153,2%
(Average = 100%)
Displacement factor: 110%
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0,94
(Structure weight / hull surface area: 85 lbs / square foot or 417 Kg / square metre)
Relative longitudinal hull strength: 1,92
(for 19,52 ft / 5,95 m average freeboard, freeboard adjustment 5,89 ft)
Relative composite hull strength: 1,01

11

Sunday, June 22nd 2003, 6:25pm

Damn ! I should have posted that design I had right away, but I was not sure wether the 40x40 was correct or the 35x35 I used so I waited.
*Smacks head on keyboard*

I was also not sure wether four 20mm were used in the mount or 6. Am I correct that the line right above the superstructure on the side view are guns 5 and 6 ?
I also think you cheated a bit on the 5.25 inch guns (using 133mm gives you 5.23"), but what difference would one ton make :-)

BTW, there is no need to worry that much about an even number of pixels on the beam. I used that when working on the top view of the Kii, but the two triple 15" guns and the two triple 5" guns gave me a headache since both types used an even number of pixels for barrel width.
An even number of pixels used for barrel width and an odd number of pixels used for the beam.
^^;;

I tried to mess around a bit with darker grey for the outline, but I didn't really like it so I went for an even number of pixels instead. Looked much better

Walter

12

Sunday, June 22nd 2003, 6:44pm

For you, Hooman

Here they are...

Design A

RSAN Hooman, South Africa, Cruiser, laid down 1935

Displacement:
5,308 t light; 5,488 t standard; 6,434 t normal; 7,165 t full load
Loading submergence 416 tons/feet

Dimensions:
470.37 ft x 49.21 ft x 19.46 ft (normal load)
143.37 m x 15.00 m x 5.93 m

Armament:
8 - 5.25" / 133 mm guns (4 Main turrets x 2 guns, 2 superfiring turrets)
16 - 1.57" / 40 mm AA guns
14 - 0.79" / 20 mm guns
Weight of broadside 613 lbs / 278 kg

Armour:
Belt 2.00" / 51 mm, ends unarmoured
Belts cover 121 % of normal area
Main turrets 1.00" / 25 mm
Armour deck 1.00" / 25 mm, Conning tower 4.00" / 102 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 76,699 shp / 57,218 Kw = 32.50 kts
Range 10,000nm at 15.00 kts

Complement:
359 - 466

Cost:
£2.827 million / $11.307 million

Distribution of weights at normal displacement:
Armament: 77 tons, 1.2 %
Armour: 628 tons, 9.8 %
Belts: 256 tons, 4.0 %, Armament: 73 tons, 1.1 %, Armour Deck: 269 tons, 4.2 %
Conning Tower: 30 tons, 0.5 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 2,179 tons, 33.9 %
Hull, fittings & equipment: 2,374 tons, 36.9 %
Fuel, ammunition & stores: 1,126 tons, 17.5 %
Miscellaneous weights: 50 tons, 0.8 %

Metacentric height 2.6

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: 1.26
Shellfire needed to sink: 5,649 lbs / 2,562 Kg = 78.1 x 5.3 " / 133 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0.9
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 54 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.28
Relative quality as seaboat: 1.08

Hull form characteristics:
Block coefficient: 0.500
Sharpness coefficient: 0.34
Hull speed coefficient 'M': 7.73
'Natural speed' for length: 21.69 kts
Power going to wave formation at top speed: 64 %
Trim: 50
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 120.0 %
Relative accommodation and working space: 150.2 %
(Average = 100%)
Displacement factor: 114 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0.96
(Structure weight / hull surface area: 89 lbs / square foot or 433 Kg / square metre)
Relative longitudinal hull strength: 2.00
(for 19.46 ft / 5.93 m average freeboard, freeboard adjustment 5.59 ft)
Relative composite hull strength: 1.04




Design B

RSAN Hooman, South Africa, Cruiser, laid down 1935

Displacement:
5,308 t light; 5,488 t standard; 6,434 t normal; 7,165 t full load
Loading submergence 416 tons/feet

Dimensions:
470.37 ft x 49.21 ft x 19.46 ft (normal load)
143.37 m x 15.00 m x 5.93 m

Armament:
8 - 5.25" / 133 mm guns (4 Main turrets x 2 guns, 2 superfiring turrets)
16 - 1.57" / 40 mm AA guns
20 - 0.79" / 20 mm guns
Weight of broadside 615 lbs / 279 kg

Armour:
Belt 2.00" / 51 mm, ends unarmoured
Belts cover 121 % of normal area
Main turrets 1.00" / 25 mm
Armour deck 1.00" / 25 mm, Conning tower 4.00" / 102 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 76,699 shp / 57,218 Kw = 32.50 kts
Range 10,000nm at 15.00 kts

Complement:
359 - 466

Cost:
£2.827 million / $11.310 million

Distribution of weights at normal displacement:
Armament: 77 tons, 1.2 %
Armour: 628 tons, 9.8 %
Belts: 256 tons, 4.0 %, Armament: 73 tons, 1.1 %, Armour Deck: 269 tons, 4.2 %
Conning Tower: 30 tons, 0.5 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 2,179 tons, 33.9 %
Hull, fittings & equipment: 2,374 tons, 36.9 %
Fuel, ammunition & stores: 1,126 tons, 17.5 %
Miscellaneous weights: 50 tons, 0.8 %

Metacentric height 2.6

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: 1.26
Shellfire needed to sink: 5,647 lbs / 2,561 Kg = 78.0 x 5.3 " / 133 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0.9
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 54 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.28
Relative quality as seaboat: 1.08

Hull form characteristics:
Block coefficient: 0.500
Sharpness coefficient: 0.34
Hull speed coefficient 'M': 7.73
'Natural speed' for length: 21.69 kts
Power going to wave formation at top speed: 64 %
Trim: 50
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 120.0 %
Relative accommodation and working space: 150.2 %
(Average = 100%)
Displacement factor: 114 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0.96
(Structure weight / hull surface area: 89 lbs / square foot or 433 Kg / square metre)
Relative longitudinal hull strength: 2.00
(for 19.46 ft / 5.93 m average freeboard, freeboard adjustment 5.59 ft)
Relative composite hull strength: 1.04


Walter

HoOmAn

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13

Sunday, June 22nd 2003, 6:59pm

Damn close!

Looks like your Intel. Service is quite good. Well done!

harry the red

Unregistered

14

Sunday, June 22nd 2003, 7:00pm

Quoted

Originally posted by HoOmAn

- I like small and fast cruisers more than big ones what you surely have noticed from older discussions so the DIDOs fitted in that sheme too.

- I also think there is not too much armor necessary on a cruiser. Studying the fights of WW2 one gets the impression that other things like redundancy of important systems is more important. So the ship got 2 main FC plus 4 specialized AA fire directors but somewhat thin armor.

I totally agree with what you are saying HoOmAn. I have also been designing a class of cruisers, which in some ways are very similar to what you got. What is different is that I had decided to dispense with armour completely, apart from rudimentary splinter protection around the magazines and armament. Their weight is also around 1000 tonnes less and will
be built to the same structurally standard as Destroyers.

The reason for this is that I had concluded that Greece not having far away territories and the associated extended sea lanes to patrol, did not require normal light cruisers. When I combined that thought with the fact that the treaty also limited the number of Type A destroyers to less then what I actually needed, I concluded that my light cruiser tonnage would best be utilised in the construction of a class of super destroyer/cruiser hybrids.


Once I complete the drawing for this class I will post it.

Harry

15

Sunday, June 22nd 2003, 7:13pm

close

Shes a fine looking ship Hoo....and while we are on the subject how does this sound for a design? I've yet to springsharp the design but would a 6x6",12x4.5" DP layout work? By placing the 6" in two triples i would have a good surface armament and with the 4.5" i could have a good DP mount but would both of them on the same hull work? Could you see any complications with a design like that?

HoOmAn

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16

Sunday, June 22nd 2003, 7:48pm

Problems

You would face problems with FC when trying to spot splashes. The calibers are too close together - and you´ll pretty sure use those 4.5" guns against surface targets if possible.

17

Sunday, June 22nd 2003, 11:30pm

never thought of that

The shell splash FC problem never entered my mind, but thats a very good point. That makes those 5.25's look that much more attractive, a large enough caliber to fight cruisers yet small enough to be used as AA weapons.

HoOmAn

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18

Monday, June 23rd 2003, 12:04am

That´s correct!

Exactement!