Shipbucket

Comox class, hopefully final revision.

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Worklist:
FFG Halifax Redraw

Just to play devils advocate what would happen if you removed all the Armour ?
Design 1, CA 3kt 1937 laid down 1937

Displacement:
2,208 t light; 2,310 t standard; 2,499 t normal; 2,651 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(413.04 ft / 405.00 ft) x 40.00 ft x (12.00 / 12.49 ft)
(125.89 m / 123.44 m) x 12.19 m x (3.66 / 3.81 m)

Armament:
8 - 4.70" / 119 mm 45.0 cal guns - 51.92lbs / 23.55kg shells, 150 per gun
Dual purpose guns in deck and hoist mounts, 1937 Model
4 x Twin mounts on centreline, evenly spread
2 raised mounts
8 - 1.57" / 39.9 mm 45.0 cal guns - 1.94lbs / 0.88kg shells, 2,000 per gun
Anti-air guns in deck and hoist mounts, 1937 Model
2 x Quad mounts on sides amidships
2 raised mounts
Weight of broadside 431 lbs / 195 kg
Main Torpedoes
4 - 21.0" / 533 mm, 21.00 ft / 6.40 m torpedoes - 1.430 t each, 5.720 t total
In 1 sets of deck mounted centre rotating tubes
Main DC/AS Mortars
2 - 190.00 lbs / 86.18 kg Depth Charges + 30 reloads - 2.714 t total
in Stern depth charge racks

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.50" / 13 mm - 0.50" / 13 mm
2nd: 0.50" / 13 mm - 0.50" / 13 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 44,870 shp / 33,473 Kw = 34.00 kts
Range 5,400nm at 12.00 kts
Bunker at max displacement = 341 tons

Complement:
176 - 229

Cost:
£1.504 million / $6.017 million

Distribution of weights at normal displacement:
Armament: 116 tons, 4.7 %
- Guns: 101 tons, 4.1 %
- Weapons: 15 tons, 0.6 %
Armour: 7 tons, 0.3 %
- Armament: 7 tons, 0.3 %
Machinery: 1,118 tons, 44.7 %
Hull, fittings & equipment: 767 tons, 30.7 %
Fuel, ammunition & stores: 291 tons, 11.7 %
Miscellaneous weights: 200 tons, 8.0 %
- Hull below water: 50 tons
- On freeboard deck: 50 tons
- Above deck: 100 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
881 lbs / 400 Kg = 17.0 x 4.7 " / 119 mm shells or 0.4 torpedoes
Stability (Unstable if below 1.00): 1.11
Metacentric height 1.6 ft / 0.5 m
Roll period: 13.5 seconds
Steadiness - As gun platform (Average = 50 %): 76 %
- Recoil effect (Restricted arc if above 1.00): 0.85
Seaboat quality (Average = 1.00): 1.52

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and large transom stern
Block coefficient (normal/deep): 0.450 / 0.458
Length to Beam Ratio: 10.13 : 1
'Natural speed' for length: 23.09 kts
Power going to wave formation at top speed: 66 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 16.00 %, 30.00 ft / 9.14 m, 23.00 ft / 7.01 m
- Forward deck: 50.00 %, 23.00 ft / 7.01 m, 23.00 ft / 7.01 m
- Aft deck: 21.00 %, 15.00 ft / 4.57 m, 15.00 ft / 4.57 m
- Quarter deck: 13.00 %, 15.00 ft / 4.57 m, 15.00 ft / 4.57 m
- Average freeboard: 20.73 ft / 6.32 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 162.8 %
- Above water (accommodation/working, high = better): 219.5 %
Waterplane Area: 10,734 Square feet or 997 Square metres
Displacement factor (Displacement / loading): 81 %
Structure weight / hull surface area: 35 lbs/sq ft or 171 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.41
- Longitudinal: 3.05
- Overall: 0.50
Cramped machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

So to compare,

protected -------- 3,189 t standard ----- £1.972 million
none protected ----- 2,310 t standard ------ £1.504 million
Tribal class DD ----- 1,850 tons (standard) ------ ?

Is this nearly a 1/3 in weight and 1/4 in cost worth it ? I'm not sure and nobody did it in real life (but that may just be due to tonnage limiting treaty's pre 37 and post 37 capacity to make plate needed more for BB's / CV's / CA's ?).
Also interesting that the real Tribal class is 400t lighter than my none protected one, I have Dp 4.7's + 2nd 40mm quad, but it has 36 Kn.
Its up to you but I think I would just build a slightly bigger Tribal class DD with Dp 4.7's (would I use better designed 4.7"/50 (12 cm) QF Mark XI or 4.5s with separate change/shell )? (and in real life the RCN did build 8 just a bit to late ! but the first RN one was Laid down 9 June 1936 and Commissioned 3 May 1938 so it fits time wise.). And as Canada would have to import the plate (or build stuff to make it , I don't think she can make it in 37) so the larger Tribal will be more home grown (still may have to import loads of stuff (what about using US 5"/38 (12.7 cm) Mark 12 ? just claim it will help rearming as not using limited GB capacity ?).
I kept a small DC set as I think all smallish escorts should have them (after all this really is a big DD).


a try at a us 5inch bigger Tribal with 2 quad 40mm etc (shows how much bigger full DP turrets are !).

Edit- Yes the above is just a 5 mins cut and past with US weapons and lots of thing wrong with it All mine so im not sure Novice deserves to join me in the blame

JSB


Edit : I have done the same but with a bit of thought is way to little I would go 300 (or more like 400 especially if you are going for Dp guns. Tribals: 200 rounds SAP + 50 rounds HE and 50 rounds star shell )

The top design is undoable - too much top-weight. Neither drawing is well executed. Apologies to JSB and to Novice but these drawings make me cringe.

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Keep well and keep drawing,

Monty