Cruisers

[Kaiser Kirk]

Pouseki Class,  Parthian Cruiser laid down 1932

C - 35  Laid 1932.0
C - 36  Laid 1932.0

Displacement:
   8,000 t light; 8,532 t standard; 9,880 t normal; 10,959 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (524.93 ft / 518.37 ft) x 54.66 ft x (26.25 / 28.31 ft)
   (160.00 m / 158.00 m) x 16.66 m  x (8.00 / 8.63 m)

Armament:
      10 - 6.50" / 165 mm 55.0 cal guns - 176.37lbs / 80.00kg shells, 270 per gun
     Quick firing guns in deck and hoist mounts, 1932 Model
     3 x 2-gun mounts on centreline ends, majority forward
      1 raised mount - superfiring
     4 x Single mounts on sides, forward deck aft
      2 raised mounts - superfiring
      8 - 3.54" / 90.0 mm 54.0 cal guns - 24.25lbs / 11.00kg shells, 400 per gun
     Anti-air guns in deck and hoist mounts, 1929 Model
     2 x 2-gun mounts on sides amidships
      2 raised mounts
     2 x 2-gun mounts on centreline ends, evenly spread
      2 double raised mounts
      16 - 1.46" / 37.0 mm 90.0 cal guns - 1.79lbs / 0.81kg shells, 900 per gun
     Anti-air guns in deck and hoist mounts, 1929 Model
     4 x 4-gun mounts on side ends, evenly spread
      4 raised mounts
      16 - 0.91" / 23.0 mm 120.0 cal guns - 0.44lbs / 0.20kg shells, 3,000 per gun
     Breech loading guns in deck mounts, 1929 Model
     8 x Twin mounts on sides, evenly spread
      8 double raised mounts
      Weight of broadside 1,993 lbs / 904 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   4.72" / 120 mm   373.23 ft / 113.76 m   10.86 ft / 3.31 m
   Ends:   1.38" / 35 mm   145.11 ft / 44.23 m   10.86 ft / 3.31 m
     Main Belt covers 111 % of normal length
     Main Belt inclined -12.00 degrees (positive = in)

   - Hull void:
      0.00" / 0 mm     0.00 ft / 0.00 m   0.00 ft / 0.00 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.56" / 65 mm   1.57" / 40 mm      1.97" / 50 mm
   2nd:   0.59" / 15 mm         -         0.31" / 8 mm
   3rd:   0.31" / 8 mm         -         0.31" / 8 mm
   4th:   0.31" / 8 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 1.57" / 40 mm
   Forecastle: 1.38" / 35 mm  Quarter deck: 1.57" / 40 mm

   - Conning towers: Forward 5.91" / 150 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 88,387 shp / 65,937 Kw = 32.00 kts
   Range 4,184nm at 22.00 kts
   Bunker at max displacement = 2,427 tons

Complement:
   495 - 644

Cost:
   £3.853 million / $15.413 million

Distribution of weights at normal displacement:
   Armament: 569 tons, 5.8 %
      - Guns: 569 tons, 5.8 %
   Armour: 1,566 tons, 15.9 %
      - Belts: 853 tons, 8.6 %
      - Armament: 122 tons, 1.2 %
      - Armour Deck: 533 tons, 5.4 %
      - Conning Tower: 59 tons, 0.6 %
   Machinery: 2,609 tons, 26.4 %
   Hull, fittings & equipment: 2,760 tons, 27.9 %
   Fuel, ammunition & stores: 1,880 tons, 19.0 %
   Miscellaneous weights: 497 tons, 5.0 %
      - Hull below water: 29 tons
      - Hull void weights: 135 tons
      - Hull above water: 16 tons
      - On freeboard deck: 175 tons
      - Above deck: 142 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     7,918 lbs / 3,592 Kg = 57.8 x 6.5 " / 165 mm shells or 1.2 torpedoes
   Stability (Unstable if below 1.00): 1.08
   Metacentric height 2.3 ft / 0.7 m
   Roll period: 15.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.74
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has rise forward of midbreak,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.465 / 0.478
   Length to Beam Ratio: 9.48 : 1
   'Natural speed' for length: 22.77 kts
   Power going to wave formation at top speed: 59 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 12.00 degrees
   Stern overhang: -6.56 ft / -2.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   18.00 %,  26.25 ft / 8.00 m,  23.79 ft / 7.25 m
      - Forward deck:   41.00 %,  23.79 ft / 7.25 m,  21.33 ft / 6.50 m
      - Aft deck:   31.00 %,  13.12 ft / 4.00 m,  13.12 ft / 4.00 m
      - Quarter deck:   10.00 %,  13.12 ft / 4.00 m,  14.11 ft / 4.30 m
      - Average freeboard:      19.14 ft / 5.83 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 107.1 %
      - Above water (accommodation/working, high = better): 130.2 %
   Waterplane Area: 18,302 Square feet or 1,700 Square metres
   Displacement factor (Displacement / loading): 107 %
   Structure weight / hull surface area: 92 lbs/sq ft or 448 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.83
      - Longitudinal: 1.87
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Warning: Beam between bulkheads too wide

Mission
This ship is meant to be a hunter.

At dusk or in poor weather, a division of 4 will  will start a sweep at 22knots, seeking a way around the enemy battle line, seeking suport ships, tankers, or carriers. The 165mm guns are expected to be effective at closer ranges of night or weather.

The range, to support this plan, is immense, with a 19.0% fuel fraction, which is very high.That is however the upper end of what I find 'reasonable'.

Years ago I simmed empty USN WWII hulls, and came up with the idea that 19% fuel seems about the upper end of what they had. So I use 20% as a limit for my ships.

Overtake
Conceptually, if steaming at 22knots cruise, and meeting a vessel steaming at 14knots cruise, there would be a +8 knot advantage.

Assuming the ship traveling 14knots was steaming directly away, and immediately went to flank speed when the range was 21km and the mast tops were visible, but not the hull.

A carrier turning to launch, or a ship delaying flank speed, or if the Parthians are charging towards a spot, and they close faster. The same math works for them escaping as well.

Assuming both ships gained 1 knot per 2 minute turn, (aka non-Destroyers), it would take 38 minutes for the 14knot to hit 33knots (if they can) and slowly pull away. 

In that time, the Pouseki would have closed 4.7nm or
7.425km, down to 13.5km. At that range the 165mm can cause a fair amount of damage. With A, B and S1,2,3 &4 bearing, 8 guns firing.

A ship moving 34knots would have a 2 knot advantage, and be able to pull away slowly, but would take an hour to reach 17km, and 2 hours to reach 20km. During which time a hail of 165mm hits may adversely effect performance.


Weaponry
From 1929.5 to 1931.0 the 165L55 is developed.
I thought I developed the 165L47, but looking at my turnsheets, it was L55.

With 1925 Tech, a 165L55 firing a 67.11 normal or *20% overwieght shell
is possible.  67.11 * 1.2 = 80.53kg as maximum shell weight.
Parthia considers 80-90kg the maximum reasonable handloading,
and a 165 firing a 80kg seems more compact than a 180L45,
and has better sectional density. 

Power assist for loading/ramming/training  is provided (10% main armanent weight), like the British 7.5".


The main armament is
            C  (E)
A (B)                             Y
            D  (F)

Centerline are 2-gun, flanking guns  are singles
Giving 8 guns forward, 8 broadside and 4 aft

Which is a good chase armament

Armor
Armor Belt is covers from from +1.5m to -1.7m
and is outsloped 15deg
3.2/cos (15) = 3.31288= 3.313 = 3.31

Range
2407  tons of fuel with geared drives (+15%) = 2768 effective tons

1,440 @ 33 knots
4,680 @ 22 knots
10,400 @ 16 knots
29,080 @ 10 knots

Misc. Weight :
100t: Construction Resv

57t : FC - 1930
25t : LR Radio
25t : Searchlight tower (NF)
25t : Hulesmeyer proximity detector
10t :  Radio Jammer / RDF
0t   :  SR Radio

5t : Paravanes
52t : 4T3 21" TT + 4 roll down shutters (4t)
50t : Midships Scout & Fighter Floatplanes
10t : Gunpowder Cat Athwartships
10t : hanger
48t : Power Assist Main Battery Load/Ram/Train

HAW
8t : CO2 Compressor AC
8t : Additional Fire Suppresion

HBW
8t : Extra Pumps
6t :  5t extra AvGas, 1t Doublewall tank
15t : Enhanced Hydrophones

Decks :
+9.00
+6.50 : Forecastle deck
+4.00 : Battery deck/ weather deck
+1.50 : Main Armor deck, top main belt
-1.00 : 2nd deck
           -1.50 : Bottom of armor belt
-3.50 :1st platform deck
-6.50 : Engineering
-6.73 : double bottom
-8.00 : Keel