It didn't occur to me until unfortunately late in the process of planning this refit to wonder how much more life the now 17 year old 25 class has in them, given the fragility of destroyer construction.
I find myself forced to shrug and assume that the hulls will be good for more than the march of progress will allow them, if I don't want to waste all the effort I've already put towards doing up art of the new version.
(no, it's not done yet, not right away, sorry.)
Anyway. The refit replaces the armament with new equipment and adds sonar and radar capability... My back-of-the-envelope numbers make me think that the depth charge allowance is enough for about sixteen, which'll need replacing after just one engagement but is better than nothing. Cost would be 377 tons and a hair under three months in drydock.
25-Improved, Nordmark Destroyer laid down 1925 (Engine 1942)
Displacement:
1,506 t light; 1,558 t standard; 1,744 t normal; 1,893 t full load
Dimensions: Length overall / water x beam x draught
345.84 ft / 341.99 ft x 31.99 ft x 12.40 ft (normal load)
105.41 m / 104.24 m x 9.75 m x 3.78 m
Armament:
4 - 4.33" / 110 mm guns (2x2 guns), 44.09lbs / 20.00kg shells, 1942 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread
12 - 1.57" / 40.0 mm guns (3x4 guns), 2.05lbs / 0.93kg shells, 1942 Model
Anti-aircraft guns in deck mounts with hoists
on centreline, evenly spread, all raised mounts
Weight of broadside 201 lbs / 91 kg
Shells per gun, main battery: 150
6 - 24.0" / 610 mm above water torpedoes
Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.98" / 25 mm -
2nd: 0.98" / 25 mm 0.98" / 25 mm -
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 42,808 shp / 31,935 Kw = 34.80 kts
Range 5,650nm at 14.00 kts
Bunker at max displacement = 335 tons
Complement:
134 - 175
Cost:
£0.642 million / $2.568 million
Distribution of weights at normal displacement:
Armament: 23 tons, 1.3 %
Armour: 18 tons, 1.0 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 18 tons, 1.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 885 tons, 50.8 %
Hull, fittings & equipment: 523 tons, 30.0 %
Fuel, ammunition & stores: 239 tons, 13.7 %
Miscellaneous weights: 56 tons, 3.2 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
478 lbs / 217 Kg = 11.8 x 4.3 " / 110 mm shells or 0.3 torpedoes
Stability (Unstable if below 1.00): 1.20
Metacentric height 1.3 ft / 0.4 m
Roll period: 12.0 seconds
Steadiness - As gun platform (Average = 50 %): 52 %
- Recoil effect (Restricted arc if above 1.00): 0.42
Seaboat quality (Average = 1.00): 0.85
Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.450
Length to Beam Ratio: 10.69 : 1
'Natural speed' for length: 21.12 kts
Power going to wave formation at top speed: 70 %
Trim (Max stability = 0, Max steadiness = 100): 61
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.78 ft / 6.64 m
- Forecastle (15 %): 16.99 ft / 5.18 m
- Mid (45 %): 16.99 ft / 5.18 m (12.70 ft / 3.87 m aft of break)
- Quarterdeck (15 %): 12.70 ft / 3.87 m
- Stern: 12.70 ft / 3.87 m
- Average freeboard: 14.92 ft / 4.55 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 177.7 %
- Above water (accommodation/working, high = better): 75.8 %
Waterplane Area: 7,249 Square feet or 673 Square metres
Displacement factor (Displacement / loading): 70 %
Structure weight / hull surface area: 35 lbs/sq ft or 170 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 2.20
- Overall: 0.58
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather
56t Misc Weight:
9 tons sonar
3 tons 40mm fire direction radar
6 tons 110mm fire direction radar
5 tons search radar
6x 3 tons per torpedo = 15 tons
18 tons depth charge racks + 60 charges