Shipbucket

Very nice work. A mini-battleship heavy cruiser that actually looks like it could work.

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Hood's Worklist
English Electric Canberra FD
Interwar RN Capital Ships
Super-Darings
Never-Were British Aircraft

Interesting looking ship with a nice design and compact, I like it. Interesting seeing all these cruisers popping up on the forums recently.

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"The first rule is not to lose; The second rule is not to forget the first rule"

With that armor information I decided to SS this bad boy. And boy is she bad...

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Baladonia, Recherche Heavy Cruiser laid down 1936

Displacement:
11,674 t light; 12,169 t standard; 13,044 t normal; 13,744 t full load

Dimensions: Length overall / water x beam x draught
598.08 ft / 590.55 ft x 65.62 ft x 22.97 ft (normal load)
182.29 m / 180.00 m x 20.00 m x 7.00 m

Armament:
6 - 10.00" / 254 mm guns (2x3 guns), 500.00lbs / 226.80kg shells, 1936 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread
8 - 4.02" / 102 mm guns (4x2 guns), 32.38lbs / 14.69kg shells, 1936 Model
Dual purpose guns in deck mounts with hoists
on side, all aft, all raised mounts - superfiring
8 - 1.57" / 40.0 mm guns (2x4 guns), 1.95lbs / 0.89kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on side, all forward, all raised mounts - superfiring
4 - 1.57" / 40.0 mm guns (1x4 guns), 1.95lbs / 0.89kg shells, 1936 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
10 - 0.79" / 20.0 mm guns (5x2 guns), 0.24lbs / 0.11kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 4 raised mounts
Weight of broadside 3,285 lbs / 1,490 kg
Shells per gun, main battery: 125

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5.98" / 152 mm 377.30 ft / 115.00 m 9.84 ft / 3.00 m
Ends: 2.99" / 76 mm 164.04 ft / 50.00 m 9.84 ft / 3.00 m
49.21 ft / 15.00 m Unarmoured ends
Upper: 4.02" / 102 mm 377.30 ft / 115.00 m 9.84 ft / 3.00 m
Main Belt covers 98 % of normal length

- Torpedo Bulkhead:
1.57" / 40 mm 377.30 ft / 115.00 m 22.97 ft / 7.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 5.98" / 152 mm 4.33" / 110 mm 5.98" / 152 mm
2nd: 1.97" / 50 mm - -
3rd: 1.18" / 30 mm - -
4th: 1.18" / 30 mm - -
5th: 0.79" / 20 mm - -

- Armour deck: 2.17" / 55 mm, Conning tower: 5.98" / 152 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 59,477 shp / 44,370 Kw = 28.00 kts
Range 6,000nm at 15.00 kts
Bunker at max displacement = 1,575 tons

Complement:
609 - 793

Cost:
£5.205 million / $20.820 million

Distribution of weights at normal displacement:
Armament: 411 tons, 3.1 %
Armour: 3,949 tons, 30.3 %
- Belts: 1,744 tons, 13.4 %
- Torpedo bulkhead: 505 tons, 3.9 %
- Armament: 582 tons, 4.5 %
- Armour Deck: 1,047 tons, 8.0 %
- Conning Tower: 71 tons, 0.5 %
Machinery: 1,669 tons, 12.8 %
Hull, fittings & equipment: 5,495 tons, 42.1 %
Fuel, ammunition & stores: 1,370 tons, 10.5 %
Miscellaneous weights: 150 tons, 1.1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
24,071 lbs / 10,918 Kg = 48.1 x 10.0 " / 254 mm shells or 3.9 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 3.3 ft / 1.0 m
Roll period: 15.2 seconds
Steadiness - As gun platform (Average = 50 %): 67 %
- Recoil effect (Restricted arc if above 1.00): 0.76
Seaboat quality (Average = 1.00): 1.67

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.513
Length to Beam Ratio: 9.00 : 1
'Natural speed' for length: 24.30 kts
Power going to wave formation at top speed: 51 %
Trim (Max stability = 0, Max steadiness = 100): 40
Bow angle (Positive = bow angles forward): 16.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 26.25 ft / 8.00 m
- Forecastle (20 %): 26.25 ft / 8.00 m
- Mid (50 %): 22.97 ft / 7.00 m
- Quarterdeck (15 %): 22.97 ft / 7.00 m
- Stern: 22.97 ft / 7.00 m
- Average freeboard: 24.11 ft / 7.35 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 97.1 %
- Above water (accommodation/working, high = better): 193.9 %
Waterplane Area: 26,128 Square feet or 2,427 Square metres
Displacement factor (Displacement / loading): 122 %
Structure weight / hull surface area: 123 lbs/sq ft or 598 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.92
- Longitudinal: 2.11
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

A most excellent design!

Thanks eltf177

I've been trying to do some planning for recent naval force structures and I have a couple of questions;

1) Nuke or diesel?

I keep changing my mind between a large ocean going SSK around 4000 tonnes similar to the Collins or Soryu, or a smallish nuke like a Trafalgar - in the context of the Recherche Navy I figure on these pros for each propulsion system in order of importance:

Conventional:
- Less crew
- Less specialised infrastructure (I'm still unsure if Recherche will have any nuclear power plants)
- More hulls for the resources (money or personnel) - probably around 8
- Slightly smaller

Nuclear:
- Higher speed (both maximum and transit)
- Can run with carrier groups effectively
- Plenty of power for systems and sensors
- Excellent range

Some requirements would be:
- Good range
- Carriage of up to 30 weapons
- Top end systems and sensors
- Good availability

I guess the requirements fit a nuke boat the best but I'm just concerned about the high crew and infrastructure requirements along with a lower number of hulls...


2) Appropriate CATOBAR carrier size

I'm thinking around 35,000 tonnes for service entry in the early to mid-1980s and then a 40-45,000 tonne replacement probably later this decade.

Primary roles would be as an ASW and fleet air defence carrier, with the ability to act as a useful strike carrier.

Standard ASW air group would likely be:
- 12 fighters (either ~30,000lbs MTOW or the HAe Tempest which is around F/A-18 size and weight – I haven't yet decided)
- 6-8 S2 Trackers (and eventual replacement)
- 3 E1 Tracers and
- 4-6 ASW/SAR helicopters

Wartime strike air group would be as above but with 16 extra fighters replacing most or all of the Trackers.

Would this be a reasonable/appropriate carrier size for a middle power? I considered STOVL and STOBAR configurations for lower costs, but I wanted fixed wing ASW/AEW assets and the ability to maintain fighter commonality with the air force. Also for the 1980's carrier would it be best to go with an all steam power plant or combined with gas turbines somehow?


Any quips, queries or qualms?

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Re 1) I believe that smallest combat sub in operation is French Rubis (2400/2600t displacement), but Argentina was (and seems to be again) working on a nuclear version of TR-1700.
http://en.wikipedia.org/wiki/CAREM.

Re 2) In the late 1980s French Clemenceau/Foch CV's (27300/32780t displacement) had an air group of up to: 16 Super Etendard, 3 Etendard IVP, 10 Crusader, 7 Alize and 2 Dauphin II (total 38), so what You have seems a reasonable solution, and in wartime I guess that these 12-16 extra fighters could be possibly added even without removing S-2's.

That's the question. You're the same size as a Clemenceau or an Essex, so you're going to need about 140 to 150 kshp. In the 1980s you still need some steam to run your catapults even if it's just a small boiler. Gas turbine output is still roughly under 30kshp so that's no fewer than four turbines for the ship (and likely five or six). That's a lot of uptake and intake volume you need. The major downside of a steam plant is that it can be very temperamental and require a larger crew.

The short version is that I would look at all steam (with diesel backups) for the 1980s design and likely a Combined Diesel Electric and Gas Electric with Steam regen for the modern design. (CODLAGLAS*?)

*In short, the power plant from hell.

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𝐌𝐀𝐓𝐇𝐍𝐄𝐓- 𝑻𝒐 𝑪𝒐𝒈𝒊𝒕𝒂𝒕𝒆 𝒂𝒏𝒅 𝒕𝒐 𝑺𝒐𝒍𝒗𝒆

TJ, might be bad to say this, but what about an COSAG plant?
there are drawbacks, but it could work. if you go for an slow cruising speed and an 'burst' in combat or when launching aircraft, you COULD go for an steam cruising plant with gas turbine boost. you could even go as far as to make it COSOG, with the boilers providing steam to the catapults, generators and arrestor wires, for about the simplest combined plant possible. just clutches and valves.

sounds better then the powerplant from hell, to be honest xD

gas turbines are best if you are worried about weight AND you have an large cruising speed (or fast acceleration) diesels are the best if you want fuel efficiency, steam is the best if you want to be REALLY efficient but have problems with acceleration. carriers mostly don't worry about weight, and steam and diesel are roughly the same weight (if we include the fuel tanks, that is)

note that steam is only more efficient when at high pressure and superheated, which also makes this the most expensive solution. at lower speeds, regular steam turbine plants work just as good, and I suppose these work just as good for the catapults.

but, I am not certain on the last 2 sections, the ones who actually know thermodynamics might prove me wrong on that.

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Drawings are credited with J.Scholtens
I ask of you to prove me wrong. Not say I am wrong, but prove it, because then I will have learned something new.
Shipbucket Wiki admin

I don't know much about modern carrier design however when it comes to submarines I'm always in favour of conventional powered units than nuke boats. If I remember right nuke boats are in general louder than SSKs though the later is noisier when it comes to recharging (unless you use some form of AIP with your design).

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"The first rule is not to lose; The second rule is not to forget the first rule"

The issue I have with a COSAG plant is that if it's not COSAGL you'll have both the ducting issues and the manning issues. As for the last option (using a smaller steam plant for non-propulsive systems) would simply be a donkey boiler.

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𝐌𝐀𝐓𝐇𝐍𝐄𝐓- 𝑻𝒐 𝑪𝒐𝒈𝒊𝒕𝒂𝒕𝒆 𝒂𝒏𝒅 𝒕𝒐 𝑺𝒐𝒍𝒗𝒆

I meant the COSOG to be, steam when cruising, gas for burst and then the steam goes to the deck.
also, an low pressure plant does not have the high manning issues the high pressure plant has, though it lacks efficiency as well. I do not know how that really translates to the turbines, but IIRC at low cruising speeds the efficiency of an low pressure steam plant goes up again.....

_________________
Drawings are credited with J.Scholtens
I ask of you to prove me wrong. Not say I am wrong, but prove it, because then I will have learned something new.
Shipbucket Wiki admin