Hi all,
No drawing yet, but a SpringSharp and some assumptions to check:
[spoiler=SpringSharp]Final Countdown Cruiser, U-S-A, U-S-A Heavy Cruiser laid down 1950
Displacement:
20,281 t light; 21,137 t standard; 22,968 t normal; 24,433 t full load
Dimensions: Length overall / water x beam x draught
799.79 ft / 787.40 ft x 85.30 ft x 24.93 ft (normal load)
243.78 m / 240.00 m x 26.00 m x 7.60 m
Armament:
9 - 7.99" / 203 mm guns (3x3 guns), 335.10lbs / 152.00kg shells, 8"/55 (20.3 cm) RF Mark 16
Automatic rapid fire guns in turrets (on barbettes)
on centreline ends, majority forward, 1 raised mount - superfiring
8 - 5.98" / 152 mm guns (4x2 guns), 130.07lbs / 59.00kg shells, 6"/47DP (15.2 cm) Mark 16
Automatic rapid fire guns in turrets (on barbettes)
on side, all amidships
16 - 3.00" / 76.2 mm guns (8x2 guns), 24.03lbs / 10.90kg shells, 3"/50 (7.62 cm) Mark 33
Automatic rapid fire guns in deck mounts
on side, evenly spread
16 - 0.79" / 20.0 mm guns (8x2 guns), 0.27lbs / 0.12kg shells, 20 mm/70 (0.79") Mark 24
Automatic rapid fire guns in deck mounts
on side, evenly spread
Weight of broadside 4,445 lbs / 2,016 kg
Shells per gun, main battery: 150
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5.98" / 152 mm 511.81 ft / 156.00 m 11.09 ft / 3.38 m
Ends: 0.79" / 20 mm 275.56 ft / 83.99 m 11.09 ft / 3.38 m
Main Belt covers 100 % of normal length
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 7.99" / 203 mm 3.94" / 100 mm 7.99" / 203 mm
2nd: 6.50" / 165 mm 2.99" / 76 mm 5.98" / 152 mm
3rd: 0.79" / 20 mm - -
4th: 0.79" / 20 mm - -
- Armour deck: 3.54" / 90 mm, Conning tower: 6.69" / 170 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 125,434 shp / 93,574 Kw = 33.00 kts
Range 10,500nm at 15.00 kts
Bunker at max displacement = 3,296 tons
Complement:
932 - 1,212
Cost:
£12.158 million / $48.633 million
Distribution of weights at normal displacement:
Armament: 506 tons, 2.2 %
Armour: 5,758 tons, 25.1 %
- Belts: 1,511 tons, 6.6 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 1,136 tons, 4.9 %
- Armour Deck: 2,995 tons, 13.0 %
- Conning Tower: 117 tons, 0.5 %
Machinery: 3,001 tons, 13.1 %
Hull, fittings & equipment: 9,016 tons, 39.3 %
Fuel, ammunition & stores: 2,687 tons, 11.7 %
Miscellaneous weights: 2,000 tons, 8.7 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
37,243 lbs / 16,893 Kg = 145.9 x 8.0 " / 203 mm shells or 3.7 torpedoes
Stability (Unstable if below 1.00): 1.16
Metacentric height 5.2 ft / 1.6 m
Roll period: 15.8 seconds
Steadiness - As gun platform (Average = 50 %): 56 %
- Recoil effect (Restricted arc if above 1.00): 0.30
Seaboat quality (Average = 1.00): 1.13
Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.480
Length to Beam Ratio: 9.23 : 1
'Natural speed' for length: 32.31 kts
Power going to wave formation at top speed: 51 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 1.64 ft / 0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29.53 ft / 9.00 m
- Forecastle (20 %): 19.69 ft / 6.00 m
- Mid (50 %): 19.69 ft / 6.00 m
- Quarterdeck (15 %): 19.69 ft / 6.00 m
- Stern: 19.69 ft / 6.00 m
- Average freeboard: 20.47 ft / 6.24 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 69.9 %
- Above water (accommodation/working, high = better): 183.8 %
Waterplane Area: 45,689 Square feet or 4,245 Square metres
Displacement factor (Displacement / loading): 129 %
Structure weight / hull surface area: 141 lbs/sq ft or 687 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.01
- Longitudinal: 0.99
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Warning: Wrong mount for rapid fire gun - 3rd battery[/spoiler]
Assumptions
- We're only sending a single ship back. So unless that CVN can generate an appropriate defensive zone from on-board resources it's going to be relying on 1941 USN escorts to do the job and might therefore not be the best option. The cruiser specified has significant misc weight to account for things like sonars and big radars that might not be on a normal cruiser - it would be unfortunate indeed if our supership got nailed by an IJN sub that appeared out of nowhere.
- "No missiles" means that our best option might be immediately post-WWII designs. The peak of all-gun ship designs might be a better bet than a Burke derivative loaded down with sensors for weapons it cannot use.
- I'm assuming "no nukes" - I think that nukes are valid for an SSN, as they're designed to operate independently to a greater degree than surface ships, for which I think the absence of a support structure would prove too great a hurdle, and, as discussed, SSNs are "cheats" for the purposes of this challenge. SSBNs are just hax.
- Supply and support are biasing me heavily towards immediately post-WWII designs. A railgun supership is great until it expend the contents of the magazine and has to reload. This will take shells either in existence or stuff that's relatively (assuming the presence of a boatload of 3" VT fuses significantly shortens the time necessary to get them into production) easy for the 1941 USN to get into production.
Given the above, I've settled on a heavy cruiser based on the
Des Moines, with 8", 6" and 3" automatic cannon to generate a significant (though limited, in the case of the 8") AA capability, plus a fairly decent surface \ shore bombardment ability too. I don't think that this would carry significant ASW gear apart from the sonars - it's big ship, probably not manoeuvrable enough to run down submarines itself - but hopefully the sonar would help the ship's 1941 escorts get any hostile sub.
So, assuming that this passes sanity checks, I'll start doodling - what do we think?
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