WesWorld

A small cruiser design with powered single 6" guns derived from Greeces twin powered mounts since the 1920's. The new turret is a between deck mount. The torpedo banks are quad, port and starboard. Designed as a fleet cruiser to work with destroyers or independently. Only expected to sail the Med. The belt is just to protect the machinery, the turrets and magazine have box protection.



Fast scout, Greek Light Cruiser laid down 1938

Displacement:
4,484 t light; 4,664 t standard; 5,110 t normal; 5,466 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(447.23 ft / 435.00 ft) x 45.00 ft x (16.00 / 16.86 ft)
(136.32 m / 132.59 m) x 13.72 m x (4.88 / 5.14 m)

Armament:
4 - 6.00" / 152 mm 50.0 cal guns - 114.33lbs / 51.86kg shells, 200 per gun
Dual purpose guns in turret on barbette mounts , 1938 Model
1 x Single mount on centreline, aft deck aft
3 x Single mounts on centreline ends, evenly spread
16 - 1.57" / 40.0 mm 65.0 cal guns - 2.17lbs / 0.98kg shells, 1,000 per gun
Anti-air guns in deck mounts , 1938 Model
2 x Twin mounts on sides, evenly spread
6 x Twin mounts on centreline, evenly spread
6 raised mounts
24 - 0.79" / 20.0 mm 65.0 cal guns - 0.27lbs / 0.12kg shells, 2,000 per gun
Breech loading guns in deck mounts , 1938 Model
12 x Twin mounts on sides, evenly spread
6 raised mounts
Weight of broadside 499 lbs / 499 kg
16 - 21.0" / 533 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.00" / 51 mm 150.00 ft / 45.72 m 8.00 ft / 2.44 m
Ends: Unarmoured
Main Belt covers 53 % of normal length
Main belt does not fully cover magazines and engineering spaces

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 2.00" / 51 mm 3.00" / 76 mm

- Armour deck: 1.50" / 38 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 73,622 shp / 54,922 Kw = 34.00 kts
Range 5,000nm at 16.00 kts
Bunker at max displacement = 803 tons

Complement:
301 - 392

Cost:
£2.770 million / $11.082 million

Distribution of weights at normal displacement:
Armament: 168 tons, 3.3 %
Armour: 632 tons, 12.4 %
- Belts: 113 tons, 2.2 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 116 tons, 2.3 %
- Armour Deck: 403 tons, 7.9 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 2,016 tons, 39.5 %
Hull, fittings & equipment: 1,724 tons, 33.7 %
Fuel, ammunition & stores: 625 tons, 12.2 %
Miscellaneous weights: 50 tons, 1.0 %
- Hull below water: 50 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2,980 lbs / 1,352 Kg = 27.6 x 6.0 " / 152 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.07
Metacentric height 1.7 ft / 0.5 m
Roll period: 14.4 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.30
Seaboat quality (Average = 1.00): 0.70

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and large transom stern
Block coefficient (normal/deep): 0.571 / 0.580
Length to Beam Ratio: 9.67 : 1
'Natural speed' for length: 23.68 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 71
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 5.00 ft / 1.52 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 25.00 %, 27.00 ft / 8.23 m, 19.00 ft / 5.79 m
- Forward deck: 45.00 %, 19.00 ft / 5.79 m, 19.00 ft / 5.79 m
- Aft deck: 20.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Quarter deck: 10.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Average freeboard: 17.10 ft / 5.21 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 139.0 %
- Above water (accommodation/working, high = better): 65.1 %
Waterplane Area: 14,512 Square feet or 1,348 Square metres
Displacement factor (Displacement / loading): 98 %
Structure weight / hull surface area: 71 lbs/sq ft or 346 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.88
- Longitudinal: 1.77
- Overall: 0.94
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped
Caution: Lacks seaworthiness - very limited seakeeping ability

Why decided the Greeks to use such weapon layout? Wouldn´t a standard superfiring B turret offer much better arcs?

I'm puzzled by the caliber choice. Given that the Greeks have used 5" guns for years, I'm puzzled by the decision to use 6" guns on this design. Yes, the 6" gun will have better performance against armored targets. However, it's a good deal heavier and it seems likely that a 5" gunned version could probably carry around 8 guns versus only 4 of the 6" weapons.

She kinda reminds me of the Capitani Romani with her high B deck forward, flush with the hull.

Thanks for the feedback.

Quoted

Why decided the Greeks to use such weapon layout? Wouldn´t a standard superfiring B turret offer much better arcs?

Yes but at a cost of probably seakeeping, which is already meagre and a lot of machinery to fit in. The 3 guns aft is similar to many current greek ships and there is a desire to keep weight down towards the bow. The 4500 tons is also a convenient build point to optimise production efficiently.

Quoted

I'm puzzled by the caliber choice. Given that the Greeks have used 5" guns for years, I'm puzzled by the decision to use 6" guns on this design. Yes, the 6" gun will have better performance against armored targets. However, it's a good deal heavier and it seems likely that a 5" gunned version could probably carry around 8 guns versus only 4 of the 6" weapons.

With the trend, especially in smaller navies for super destroyers, Greece has opted for hitting power. The concept for these ships are an overgrown destroyer rather than a mini cruiser. Its expected that a faster firing 6" is a better deal than a larger number of lower velocity 5". While Greece has 5" guns they went from 5"/50 to 5"/40 is the early 30's and while they make for an all round gun they are not the best Anti-surface weapon. The 6" single is an effort to fix that.

Quoted

She kinda reminds me of the Capitani Romani with her high B deck forward, flush with the hull.

Its to try and keep the after deck dry. SS has been unkind with the sea rating and to try and get a good rating makes for some funny looking hulls.


Cheers,

Why between deck mounts?

Not having to fit all the associated machinery into the rotating structure, improving weather protection, lower profile.

Cheers,

Looks like a postwat Type 14 frigate on steriods! I like the look, not sure how efficent the tween decks turrets would be and Q mount looks pretty useless but until we see a top view its hard to say what arcs it would have not to mention blast effects on the rangefinder aft of the mount.

Still I like the innovative over the same old stuff we normally see. I say build it. It would be easy to imagine a 4-5in AA variant too. Not sure 6in is the best calibre for DP use, RoF might be quite poor against aerial targets.

Looking at that picture, I would sim the main gun layout as
2 x Single mounts on centreline ends, evenly spread
2 raised mounts
2 x Single mounts on centreline, forward deck aft
2 raised mounts

The part that I'm still dubious about is the choice of the 6" over the 5" gun. There are some 6" shells that have a noticeably larger explosive charge than the 5" shells (the US 6" HC, with a 6.0 kg explosive fill for instance), but in most cases the additional size translates more into additional metal rather than additional explosive. Additional metal's not a problem if you're shooting at armored targets, where you need the metal to penetrate armor, but I'm not sure of too many armored targets in the Med that I'd want to engage with only guns.

It's definitely different, though, so if that's design goal, it's a success.

Whats the projected rate of fire for these 6" guns and how does it compair to the competitors 5" ranged guns?

Probably around 9-10rpm for a single 152mm mounting. Turkish ships mount 150mm, 130mm and 105mm weapons. Italian ships mount 135mm weapons usually. Difference in rate of fire isn't much, maybe 10-12rpm for the 130mm guns.

The Turkish ships lack DP mounts for the most part, but then again certainly some designs are equal in number of guns. The Bozcaada and Adalari class ships for example mount the same number of 5.9" surface guns while the Seljuks in that reguard have more guns, 3x2.

For DP the 88's are adequate but more suited to AA and not surface targets vs anything larger than a TB.

5" guns can easily double most 6" guns, if the 5" gun has a hoist. See the rate of fire of the 5"/38 Mk 12: 15-22 rounds a minute for the mountings that had a hoist, 12-15 rounds a minute for the mountings without a hoist. The US 6" DP weapon had a rate of fire of 12 rounds per minute, while the Swedish 15cm/6" weapon had a rate of fire of 10 rounds per minute vs surface targets and 15 vs air targets (the British 6" weapon wasn't in service until 1959 so I'm leaving it out of consideration).

In that reguard it would seem this designs only benifit over its potential rivals is that like most Greek ships it could be built in larger numbers than Turkish Yugoslavian or Bulgarian ships which in many respects are equal or superior to this design, at least in Turkeys case with the Adalari and Seljuk classes.

Numbers don't help vs Italy as they can clearly outbuild Greece.

I am split on the gun issue. The Rood Haas DDL I considered had 6" guns as well, with the idea that you could either engage an opposing CL, OR quickly kill opposing DD. This might make it a more useful island / night raider in a pony express role.

The armor scheme would suggest this might be the case, as the deck is sufficient for long range 6" fire, while the belt is likely proof against 5" HE and SAP rounds.

That said, the belt is very small does not cover the vitals - likely by only a little, hard to tell- the text indicated a box around magazines, so perhaps it was simmed as belt length needed before weapons, and the 50tons weight is the armor boxes? With the short height there is little protected floatation, the goal seems to be to ward off critical hits.

Hull form could also likely be made more slender. With the 45foot beam and .57 BC she is not optimized for her speed. The Soemba sloops had single 6" on a 37foot beam, so there should be some room to modify her. That should both help seakeeping and reduce the length of the engine spaces, which may make the belt more effective.

Quoted

5" guns can easily double most 6" guns, if the 5" gun has a hoist.

It depends on the gun. The 6"/47DP and 152/53DP are a bit postwar and represent the hard edge. Something around 10rpm sustained from a single mounting would probably be possible with much higher burst rates. The 128/61 Zwilling mounting using fixed ammunition of similar weight to the separate 6" shells is probably a good indicator giving 11rpm.

The figures claimed for the 5"/38 are massively in excess of other period 5" and 4.7" weapons and do not seem to give an accurate representation of service rates, which seems to be about 12-14rpm from after action reports.

The RN thought that a single 6" shell would make a pretty good mess of a destroyer, but multiple 4.7" hits would be needed to achieve the same result.

The British 6"/50's shells and the British 4.7" shells had similar explosive loads, differing by only a pound or so.

The German 12.8cm/45 was rated for 18-20 rounds a minute, as were the later 12.8cm weapons (though in service the 12.8cm guns achieved closer to 15-18 most of the time aboard ship). The high rate for the US gun is probably from the integral hoists, which are noted as causing a significant speed-up in the rate of fire.

Variation on a theme: Turrets on deck rather than between deck mounts - I'll concede that X should be super firing and an update of the earlier Eurybiades scouts but 5 knots faster and still only 8x5" guns.



I guess I could fit 10 5" AA easily but that seems to be over gunned for the size and many WW designs are overgunned. I reason that single mounts will achieve higher rof that twins of the same calibre and the 6" has greater range.

So whats better? 4x2000ton destroyers with 5 or 6 5" AA or 2 of these with either 8x5" or 4x6" or a real 8000 ton cruiser with 8x6"? I'm beginning to think that the bigger ship is better value but available building capacilty may have a bearing on that.

Cheers,


Cheers,

The lower drawing I like a lot, the other one still seems odd to me.....