WesWorld

Those who were present on chat the other day will be aware of my fairly unhappy reaction to the revelation that the Gam class carriers, unlike every other existing Nordmark vessel I've examined so far, featured dual purpose 130mm mounts.

See, one of my 'design goals', if you will, is to clear up and clean up the inconsistencies I perceive looking at Nordmark's fleet. As part of that, I'd determined as a 'first principle' that I'd be standardizing across the fleet on one particular gun of any given type; for DD primary and capital-ship secondary guns, I had two existing calibers suitable for conversion, 110mm and 130mm, both of which - in the vessels I'd examined first, the destroyers suitable for quick refitting - were available only in low-angle, anti-surface mounts.

Since I had a considerable existing fleet, since it was more common, since the question of a dual-purpose mount apparently hadn't been weighed previously in character, and since the 110mm could be expected to 'fit' on a ship designed for 130mm but not vice versa, I settled on 110mm as my 'caliber of choice'.

But then there's Gam, with 130mm DP. So apparently the decision has been made in-character. Retconning it doesn't seem to be an option, not with Gam and her sister so advanced, which leaves me...

Well, about to find a big chunk of my fleet due for phasing out rather than refit. And with most of my work done so far unusable.

Ah, well. Scrapping the unsuitable vessels at least puts me considerably closer to wiping out the consequences of my predecessors lamentable lack of understanding of the fact of the backwards nature of the United States' customary system of measures.



All that said, the disposal list includes about two thirds of my destroyers, meaning I'll need to build replacements so that I can get rid of them without a major fleet draw-down.

Thus, this:


Type 42, Nordmark Destroyer laid down 1942

Displacement:
2,000 t light; 2,150 t standard; 2,643 t normal; 3,037 t full load

Dimensions: Length overall / water x beam x draught
405.32 ft / 393.70 ft x 42.65 ft x 10.83 ft (normal load)
123.54 m / 120.00 m x 13.00 m x 3.30 m

Armament:
8 - 5.12" / 130 mm guns (4x2 guns), 66.14lbs / 30.00kg shells, 1942 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread, 2 raised mounts - superfiring
8 - 1.57" / 40.0 mm guns (2x4 guns), 2.05lbs / 0.93kg shells, 1942 Model
Anti-aircraft guns in deck mounts with hoists
on side, all amidships, all raised mounts - superfiring
4 - 1.57" / 40.0 mm guns (1x4 guns), 2.05lbs / 0.93kg shells, 1942 Model
Anti-aircraft guns in a deck mount with hoist
on centreline amidships
24 - 0.79" / 20.0 mm guns (6x4 guns), 0.24lbs / 0.11kg shells, 1942 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 559 lbs / 254 kg
Shells per gun, main battery: 300
8 - 24.0" / 610 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm 0.39" / 10 mm -
4th: 0.39" / 10 mm 0.39" / 10 mm -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 49,699 shp / 37,075 Kw = 34.00 kts
Range 5,000nm at 20.00 kts
Bunker at max displacement = 887 tons

Complement:
183 - 239

Cost:
£1.873 million / $7.493 million

Distribution of weights at normal displacement:
Armament: 71 tons, 2.7 %
Armour: 21 tons, 0.8 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 21 tons, 0.8 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 1,178 tons, 44.6 %
Hull, fittings & equipment: 668 tons, 25.3 %
Fuel, ammunition & stores: 643 tons, 24.3 %
Miscellaneous weights: 62 tons, 2.3 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
701 lbs / 318 Kg = 10.5 x 5.1 " / 130 mm shells or 0.4 torpedoes
Stability (Unstable if below 1.00): 1.18
Metacentric height 1.9 ft / 0.6 m
Roll period: 13.0 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.43
Seaboat quality (Average = 1.00): 0.54

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.509
Length to Beam Ratio: 9.23 : 1
'Natural speed' for length: 22.76 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 93
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: 14.44 ft / 4.40 m
- Forecastle (15 %): 14.11 ft / 4.30 m
- Mid (30 %): 13.78 ft / 4.20 m
- Quarterdeck (15 %): 13.12 ft / 4.00 m
- Stern: 13.12 ft / 4.00 m
- Average freeboard: 13.59 ft / 4.14 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 169.1 %
- Above water (accommodation/working, high = better): 94.5 %
Waterplane Area: 11,731 Square feet or 1,090 Square metres
Displacement factor (Displacement / loading): 81 %
Structure weight / hull surface area: 39 lbs/sq ft or 191 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 0.72
- Overall: 0.51
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is adequate
Caution: Lacks seaworthiness - very limited seakeeping ability

Misc Weight:

5 tons main battery director radar
5 tons search radar
3 tons AA director radar

24 tons torpedoes and support equipment

9 tons sonar
18 tons 60x depth charges and launching racks

I'd ditch one of the 130mm turrets and try to raise seakeeping a bit - or perhaps alternately lower the range, as the ships are rather long-legged for their type.

I don't see the problem with 110mm and 130mm DP, but if you're going to stop making 110mm guns, would you please sell the 110mm equipment to Chile so I don't have to stop using the guns, please?

Some of the destroyers on the disposal list are pretty long in the tooth, but there are others that aren't. You're welcome to first refusal on them, as well as the tooling, if you like. For that matter, the civilian gun foundries that they came from aren't going to be going anywhere and would almost certainly be perfectly happy to continue supplying orders.

My (the Nordmark government's) objection is more along the lines of 'creating two such comparable weapons is silly', so the orders to created a 110mm DP design would never have been given.


Spot-checking both my Encyclopedia and some historical models, I come up with this for range...


Type 42, Nordmark Destroyer laid down 1942

Displacement:
2,000 t light; 2,145 t standard; 2,377 t normal; 2,564 t full load

Dimensions: Length overall / water x beam x draught
407.59 ft / 393.70 ft x 42.65 ft x 10.83 ft (normal load)
124.23 m / 120.00 m x 13.00 m x 3.30 m

Armament:
8 - 5.12" / 130 mm guns (4x2 guns), 66.14lbs / 30.00kg shells, 1942 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread, 2 raised mounts - superfiring
8 - 1.57" / 40.0 mm guns (2x4 guns), 2.05lbs / 0.93kg shells, 1942 Model
Anti-aircraft guns in deck mounts with hoists
on side, all amidships, all raised mounts - superfiring
4 - 1.57" / 40.0 mm guns (1x4 guns), 2.05lbs / 0.93kg shells, 1942 Model
Anti-aircraft guns in a deck mount with hoist
on centreline amidships
24 - 0.79" / 20.0 mm guns (6x4 guns), 0.24lbs / 0.11kg shells, 1942 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 559 lbs / 254 kg
Shells per gun, main battery: 300
8 - 24.0" / 610 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm 0.39" / 10 mm -
4th: 0.39" / 10 mm 0.39" / 10 mm -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 44,714 shp / 33,357 Kw = 34.00 kts
Range 5,000nm at 15.00 kts
Bunker at max displacement = 419 tons

Complement:
169 - 221

Cost:
£1.747 million / $6.988 million

Distribution of weights at normal displacement:
Armament: 71 tons, 3.0 %
Armour: 21 tons, 0.9 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 21 tons, 0.9 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 1,037 tons, 43.6 %
Hull, fittings & equipment: 809 tons, 34.0 %
Fuel, ammunition & stores: 377 tons, 15.9 %
Miscellaneous weights: 62 tons, 2.6 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
814 lbs / 369 Kg = 12.1 x 5.1 " / 130 mm shells or 0.4 torpedoes
Stability (Unstable if below 1.00): 1.13
Metacentric height 1.8 ft / 0.5 m
Roll period: 13.5 seconds
Steadiness - As gun platform (Average = 50 %): 62 %
- Recoil effect (Restricted arc if above 1.00): 0.63
Seaboat quality (Average = 1.00): 0.83

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.458
Length to Beam Ratio: 9.23 : 1
'Natural speed' for length: 22.91 kts
Power going to wave formation at top speed: 67 %
Trim (Max stability = 0, Max steadiness = 100): 75
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: 18.37 ft / 5.60 m
- Forecastle (15 %): 17.72 ft / 5.40 m
- Mid (30 %): 17.06 ft / 5.20 m
- Quarterdeck (15 %): 16.40 ft / 5.00 m
- Stern: 16.40 ft / 5.00 m
- Average freeboard: 16.97 ft / 5.17 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 168.7 %
- Above water (accommodation/working, high = better): 121.5 %
Waterplane Area: 11,199 Square feet or 1,040 Square metres
Displacement factor (Displacement / loading): 80 %
Structure weight / hull surface area: 43 lbs/sq ft or 210 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.55
- Overall: 0.56
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Misc Weight:

5 tons main battery director radar
5 tons search radar
3 tons AA director radar

24 tons torpedoes and support equipment

9 tons sonar
18 tons 60x depth charges and launching racks

I think that's a lot better, yes.

Well its no less odd than Britain's list of weapons; 3in, 3.7in, 4in and 4.5in (although now I've begun to standardise on 3.7in and 4.5in).

It's a fairly big destroyer, certainly powerful but at 2,000 tons a pop its not going to be cheap if your replacing two thirds of your destroyers.

Personally I see nothing wrong in retaining LA guns for destroyers, not all of them need to be AA units and indeed for fleet surface screening duties the 130mm LA is likely to be a better bet.

Quoted

Originally posted by Hood
Personally I see nothing wrong in retaining LA guns for destroyers, not all of them need to be AA units and indeed for fleet surface screening duties the 130mm LA is likely to be a better bet.

Honestly, given the general adoption of DP weaponry among the navies of WW, retaining an LA armament for new construction makes little sense.

As to the design, I see a few areas in which it might be improved.

1 - Reduce the number of main guns to six rather than eight. It will save a bit of top weight and magazine space.

2 - The 40mm quad on the C/L amidships is going to have very restricted sky arcs, particularly with the two 40mm quad mounts on the side and the six 20m quad mounts. If you reduce the number of main guns to six you could move the C/L 40mm quad to either "B" or "Y" positions and improve the sky arcs and working spaces.

3 - I'd limit the 20mm quad mounts to four - they are competing with deck space with the torpedo tubes and the ships' boats, and I am not certain that there would be sufficient space available.

4 - The seakeeping, while improved, is still less than I would like. It is within the spectrum allowed by the Gents' Rules, so this is a personal preference.

Quoted

Originally posted by BruceDuncan
1 - Reduce the number of main guns to six rather than eight. It will save a bit of top weight and magazine space.

I consider the AB-XY layout something of a Nordish trademark and have something of a personal dislike for AB-X designs, so going to six would involve a Q position, which'd complicate the fire arc dance immensely, or an A-XY or mix of singles and doubles, neither of which would do much good.

If this is a '2000t is slightly too small for eight' statement, I can try 2250, but I'm building around the main armament, not the other way around.

Quoted

2 - The 40mm quad on the C/L amidships is going to have very restricted sky arcs, particularly with the two 40mm quad mounts on the side and the six 20m quad mounts. If you reduce the number of main guns to six you could move the C/L 40mm quad to either "B" or "Y" positions and improve the sky arcs and working spaces.

Again, the main battery reduction is a nonstarter. The centerline 40mm mount is planned on a 'sky bridge' platform between the torpedo-tube mounts, while the side mounts go port-and-starboard between the funnels, which are well forward. Obviously, I could turn out to be wrong once I actually sit down and do the art, but I will be very surprised if the positioning is as problematic as you're expecting.

Quoted

3 - I'd limit the 20mm quad mounts to four - they are competing with deck space with the torpedo tubes and the ships' boats, and I am not certain that there would be sufficient space available.

My mental placeholders for them are 'under' B and X turret and at the aft end of the superstructure, so I'm certain that they won't interfere with the torpedo tubes. Boats, less sure, but again, I think I can make it work.

Quoted

4 - The seakeeping, while improved, is still less than I would like. It is within the spectrum allowed by the Gents' Rules, so this is a personal preference.

If you can come up a version that maintains all other functional capabilities at their current level and improves seakeeping as you desire, you're welcome to try.

Until I've seen it and double-checked the design into my own SS, however, I'm going to... take leave to continue to doubt the possibility, let us say.

So, forget everything here. I've found a way around the 13cm main battery. ^_^

I'm not abandoning the design, though, so based on that and things I've discovered during the process of actually drawing it, have another draft.


Type 42, Nordmark Destroyer laid down 1942

Displacement:
2,000 t light; 2,115 t standard; 2,345 t normal; 2,530 t full load

Dimensions: Length overall / water x beam x draught
407.21 ft / 393.70 ft x 42.65 ft x 10.83 ft (normal load)
124.12 m / 120.00 m x 13.00 m x 3.30 m

Armament:
8 - 4.33" / 110 mm guns (4x2 guns), 44.09lbs / 20.00kg shells, 1942 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread, 2 raised mounts - superfiring
8 - 1.57" / 40.0 mm guns (2x4 guns), 2.05lbs / 0.93kg shells, 1942 Model
Anti-aircraft guns in deck mounts with hoists
on side, all amidships, all raised mounts - superfiring
8 - 1.57" / 40.0 mm guns (2x4 guns), 2.05lbs / 0.93kg shells, 1942 Model
Anti-aircraft guns in deck mounts with hoists
on centreline, all amidships, all raised mounts - superfiring
Weight of broadside 386 lbs / 175 kg
Shells per gun, main battery: 300
8 - 24.0" / 610 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.39" / 10 mm -
2nd: 0.39" / 10 mm 0.39" / 10 mm -
3rd: 0.39" / 10 mm 0.39" / 10 mm -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 44,117 shp / 32,911 Kw = 34.00 kts
Range 5,000nm at 15.00 kts
Bunker at max displacement = 415 tons

Complement:
168 - 219

Cost:
£1.625 million / $6.499 million

Distribution of weights at normal displacement:
Armament: 45 tons, 1.9 %
Armour: 17 tons, 0.7 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 17 tons, 0.7 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 1,057 tons, 45.1 %
Hull, fittings & equipment: 798 tons, 34.0 %
Fuel, ammunition & stores: 345 tons, 14.7 %
Miscellaneous weights: 84 tons, 3.6 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
869 lbs / 394 Kg = 21.4 x 4.3 " / 110 mm shells or 0.4 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 1.7 ft / 0.5 m
Roll period: 13.6 seconds
Steadiness - As gun platform (Average = 50 %): 72 %
- Recoil effect (Restricted arc if above 1.00): 0.50
Seaboat quality (Average = 1.00): 0.95

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.452
Length to Beam Ratio: 9.23 : 1
'Natural speed' for length: 22.93 kts
Power going to wave formation at top speed: 67 %
Trim (Max stability = 0, Max steadiness = 100): 75
Bow angle (Positive = bow angles forward): 24.00 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.97 ft / 7.00 m
- Forecastle (15 %): 19.69 ft / 6.00 m
- Mid (30 %): 18.04 ft / 5.50 m
- Quarterdeck (15 %): 16.40 ft / 5.00 m
- Stern: 16.40 ft / 5.00 m
- Average freeboard: 17.91 ft / 5.46 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 165.7 %
- Above water (accommodation/working, high = better): 126.7 %
Waterplane Area: 11,140 Square feet or 1,035 Square metres
Displacement factor (Displacement / loading): 85 %
Structure weight / hull surface area: 41 lbs/sq ft or 200 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.87
- Overall: 0.57
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Misc Weight:

3 tons search radar
3 tons elevation radar
3 tons main battery director radar
8 tons main battery fire control computer
3x 1 ton AA director radar
3x 1 ton AA fire control computer

24 tons torpedoes and support equipment

9 tons sonar
18 tons 60x depth charges and launching racks

10 tons unplanned kipple allowance