WesWorld

Here's a proposed German CL, to be laid down in 1928. It differs from the slightly older Ersatz Arcona's in carrying it's main armament in triple turrets, vs twins, and in the choice of a 105mm AA battery versus the 88mm battery on the Ersatz Arcona's. Armor is somewhat heavier as well, probably because of the shorter belt allowed by the use of triple turrets. The reasoning behind these changes is pretty simple: going to triples allows for a shorter, and hence thicker, belt, improving the protection it offers. The 105mm cannon is a more capable gun in the LA role than the 88mm, which lacks hitting power (the 105mm isn't wonderful, but it's better).

Ersatz Medusa, Germany Light Cruiser laid down 1928

Displacement:
8,042 t light; 8,368 t standard; 9,343 t normal; 10,123 t full load

Dimensions: Length overall / water x beam x draught
642.74 ft / 623.36 ft x 62.34 ft x 18.70 ft (normal load)
195.91 m / 190.00 m x 19.00 m x 5.70 m

Armament:
9 - 5.91" / 150 mm guns (3x3 guns), 102.98lbs / 46.71kg shells, 1928 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, majority forward, 1 raised mount - superfiring
8 - 4.13" / 105 mm guns (4x2 guns), 35.32lbs / 16.02kg shells, 1928 Model
Dual purpose guns in deck mounts with hoists
on side, evenly spread
2 - 4.13" / 105 mm guns (1x2 guns), 35.32lbs / 16.02kg shells, 1928 Model
Dual purpose guns in a deck mount with hoist
on centreline aft, all raised guns - superfiring
8 - 1.46" / 37.0 mm guns (4x2 guns), 1.55lbs / 0.70kg shells, 1928 Model
Anti-aircraft guns in deck mounts
on side ends, evenly spread
16 - 0.79" / 20.0 mm guns in single mounts, 0.24lbs / 0.11kg shells, 1928 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 1,296 lbs / 588 kg
Shells per gun, main battery: 180
16 - 23.6" / 600 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 4.72" / 120 mm 364.67 ft / 111.15 m 9.48 ft / 2.89 m
Ends: Unarmoured
Main Belt covers 90 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 4.72" / 120 mm 2.76" / 70 mm 4.72" / 120 mm
2nd: 1.97" / 50 mm 0.79" / 20 mm 1.97" / 50 mm
3rd: 1.97" / 50 mm 0.79" / 20 mm 1.97" / 50 mm
4th: 0.79" / 20 mm 0.39" / 10 mm -
5th: 0.39" / 10 mm - -

- Armour deck: 1.38" / 35 mm, Conning tower: 4.72" / 120 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 67,681 shp / 50,490 Kw = 32.00 kts
Range 8,000nm at 15.00 kts
Bunker at max displacement = 1,754 tons

Complement:
474 - 617

Cost:
£2.721 million / $10.883 million

Distribution of weights at normal displacement:
Armament: 162 tons, 1.7 %
Armour: 1,730 tons, 18.5 %
- Belts: 689 tons, 7.4 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 339 tons, 3.6 %
- Armour Deck: 656 tons, 7.0 %
- Conning Tower: 45 tons, 0.5 %
Machinery: 2,107 tons, 22.6 %
Hull, fittings & equipment: 3,943 tons, 42.2 %
Fuel, ammunition & stores: 1,301 tons, 13.9 %
Miscellaneous weights: 100 tons, 1.1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
13,778 lbs / 6,250 Kg = 133.8 x 5.9 " / 150 mm shells or 1.8 torpedoes
Stability (Unstable if below 1.00): 1.17
Metacentric height 3.3 ft / 1.0 m
Roll period: 14.4 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.31
Seaboat quality (Average = 1.00): 1.22

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.450
Length to Beam Ratio: 10.00 : 1
'Natural speed' for length: 28.67 kts
Power going to wave formation at top speed: 52 %
Trim (Max stability = 0, Max steadiness = 100): 57
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 27.89 ft / 8.50 m
- Forecastle (24 %): 20.67 ft / 6.30 m
- Mid (50 %): 17.39 ft / 5.30 m
- Quarterdeck (18 %): 17.39 ft / 5.30 m
- Stern: 17.39 ft / 5.30 m
- Average freeboard: 19.27 ft / 5.87 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 88.6 %
- Above water (accommodation/working, high = better): 120.2 %
Waterplane Area: 25,747 Square feet or 2,392 Square metres
Displacement factor (Displacement / loading): 127 %
Structure weight / hull surface area: 101 lbs/sq ft or 495 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.97
- Longitudinal: 1.20
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

.

Nice design. However, her BC seems to be on the low end given her size and at 32kn she shouldn´t feature a transome stern according to our Gentlemen´s Agreement (she´s slower than 34kn, no small fast combatant and not a historical design).

Regards,

HoOmAn

The BC is based on the Italian Saint class ships, though I'll agree up front it's a bit low. The transom stern was featured on the historical German "K" class light cruisers that were launched in 1927. I'm currently trying to figure out just what ARE the rules on transoms, since there are various ships and designs with them, some of which meet the 34+ knot guideline and some of which don't.

Quoted

The BC is based on the Italian Saint class ships, though I'll agree up front it's a bit low.

It is a bit low, but I needed a large hull to fit all the guns onto. It might prove to be a bit of problem. Future cruiser designs are using a Cb of about 0.5

She seems fairly good but may be a little cramped. Any chance of a drawing of her?

Quoted

Originally posted by Red Admiral

Quoted

The BC is based on the Italian Saint class ships, though I'll agree up front it's a bit low.

It is a bit low, but I needed a large hull to fit all the guns onto. It might prove to be a bit of problem. Future cruiser designs are using a Cb of about 0.5

And I was impressed with how much fit aboard, especially the amount of armor plate. I may return to a version of the Ersatz Arcona hull before I actually lay anything down, this is, after all, a proposal.

Quoted

She seems fairly good but may be a little cramped. Any chance of a drawing of her?

If I knew how you guys were doing your drawings, I'd think about it.

I'm just using Paint.

I'll email you the .bmp files for Ersatz Arcona class and others - you could probably kibitz them easily enough.

Indian cruisers use the 10.5 cm guns as secondaries - you could borrow the design from one of my pics (see the encyclopedia).

Hmmm. OK, how does one post a picture? Rocky sent me a pick of Ersatz Arcona, and I've made mods to it to make it look more like Ersatz Medusa, but posting is proving difficult....

www.photobucket.com

Register, then you can post images direct to the forum.

And here's Ersatz Medusa.

Not bad, not bad...

Quoted

and at 32kn she shouldn´t feature a transome stern according to our Gentlemen´s Agreement (she´s slower than 34kn, no small fast combatant and not a historical design).

The same three parameters apply to the transomed-without-opposition Aquila...

Since the historical German cruisers had transoms, I don't think it's a problem anyway.

Agreed, not bad, but there's the quibble that the Springsharp calls for a flush deck, which is not the case with the pic.

As an aside, the space aft of the funnel was left for a catapult if/when Germany got planes back. I assume this is the case here as well?

Quoted

Originally posted by The Rock Doctor
Agreed, not bad, but there's the quibble that the Springsharp calls for a flush deck, which is not the case with the pic.

Agreed, haven't quite gotten to that part yet, nor have I exactly figured out how to draw it.

Quoted

As an aside, the space aft of the funnel was left for a catapult if/when Germany got planes back. I assume this is the case here as well?

Yes, though another possible use for that space (and the tonnage) is as a storage area for mines.

Here's a version with a flush deck and the raised bow the design has.

Quoted

Originally posted by Swamphen
The same three parameters apply to the transomed-without-opposition Aquila...

Just because one design escaped _us all_ we shouldn´t skip the rules we originally agreed on.

We said only small fast combatants should be allowed to have transome sterns because SS doesn´t allow DDs and TBs to be simmed properly otherwise. Lager ships were allowed such sterns only if their speed was at least 34kn.

True. However since the historical German CLs had transoms...

And if these ships are pushed back to 1930 for whatever reason it isn't an issue anyway.

If the design style is historical for a nation (remember Germany has been known to be ahead in technology before) shouldn't they be allowed to do this design. Plus they are at best a few year ahead of the agreement's 1930 limit. This gives Germany a slight advantage over the treaty nations that it would not have otherwise, and does make sense to me should it be laid down in 1928 or 1929.

Quoted

Just because one design escaped _us all_ we shouldn´t skip the rules we originally agreed on.

Just about all of the French and Russian carriers have transoms. The one on Aquila is needed to repesent the "tunnel-drive". The hull form needs to be fuller aft to incorporate the middle shafts. The disadvantage is that it adds deck armour and will reduce efficiency at cruising speed, but Aquila has a large bunkerage to offset this.

Hrolf, Any chance you could make the picture a bit bigger and less fuzzy? Maybe best to keep the same scale as Rocky. I'll send you my warship template if you give me an email address.

I used the exact picture that Rocky sent me, but take a look now, I've scaled the picture up now.

Quoted

Just because one design escaped _us all_ we shouldn´t skip the rules we originally agreed on.

ONE!?!?
Better count again, Hooman. ^_^
I found four designs with transoms that are not "small fast combattants" and/or do not exceed 34 knots:
- Carrier Gambetta 13,000 tons, 30 knots, 1925
- Carrier Aquila 22,000 tons, 30.74 knots, 1927
- Light cruiser Admiral Nakhimov 7,900 tons, 33 knots, 1926
- Battlecruiser Patagonia 26,000 tons 31 knots, 1928

... and it makes me wonder why I tried so hard to get that speed of the Soryu over 34 knots...
:-\
At least Aquila is drawn with a transom, and I think that (while not gentleman-like) RA's argument is a good one.
I might as well go and alter the Dairen design as it already goes 34 knots...

Hmm, it seems to have shrunk a bit. The first pic was better i'm afraid as then you can see all of it on screen.

Maybe thicker gun barrels.

Probably best to save files as .gif then there isn't as much distorition. A bit on colours, but its not bad with grey.