Vilnius Union Ships, 1930+: The Good, The Bad, and the Unseaworthy

[The Rock Doctor]

Refit for the river depot ship Zackwycajacy is pretty much just replacing the armament and fire control.

The cost is a very economic $0.02 and 0.011 BP.


Enter ship name, Enter country Enter ship type laid down 1914, refit 1933

Displacement:
   1,191 t light; 1,232 t standard; 1,304 t normal; 1,362 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (299.23 ft / 295.28 ft) x 42.65 ft x (5.58 / 5.79 ft)
   (91.20 m / 90.00 m) x 13.00 m  x (1.70 / 1.76 m)

Armament:
      4 - 1.97" / 50.0 mm 60.0 cal guns - 4.18lbs / 1.89kg shells, 1,500 per gun
     Anti-air guns in deck mounts, 1914 Model
     4 x Single mounts on sides, evenly spread
      4 raised mounts
      4 - 0.59" / 15.0 mm 90.0 cal guns - 0.12lbs / 0.05kg shells, 5,000 per gun
     Machine guns in deck mounts, 1914 Model
     2 x Single mounts on centreline, evenly spread
      2 raised mounts
     2 x Single mounts on sides amidships
      2 raised mounts
      Weight of broadside 17 lbs / 8 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.59" / 15 mm         -               -
   2nd:   0.59" / 15 mm         -               -

Machinery:
   Coal fired boilers, steam turbines,
   Direct drive, 2 shafts, 603 shp / 450 Kw = 10.61 kts
   Range 2,000nm at 10.00 kts
   Bunker at max displacement = 130 tons (100% coal)

Complement:
   108 - 141

Cost:
   £0.059 million / $0.238 million

Distribution of weights at normal displacement:
   Armament: 5 tons, 0.4 %
      - Guns: 5 tons, 0.4 %
   Armour: 5 tons, 0.4 %
      - Armament: 5 tons, 0.4 %
   Machinery: 26 tons, 2.0 %
   Hull, fittings & equipment: 624 tons, 47.9 %
   Fuel, ammunition & stores: 114 tons, 8.7 %
   Miscellaneous weights: 530 tons, 40.6 %
      - Hull below water: 100 tons
      - Hull above water: 100 tons
      - On freeboard deck: 304 tons
      - Above deck: 26 tons

Fittings:
-100 t:  Supply for 1,000 t of small craft (BW)
-100 t:  Crew amenities and facilities (AW)
-250 t:  Accommodation for 125 (FD)
-50 t:  Cranes and cargo handling (FD)
-4 t:  Weight reserve (FD)
-25 t:  L/R wireless (AD)
-1 t:  1930 fire control (AD)

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     12,436 lbs / 5,641 Kg = 3,260.5 x 2.0 " / 50 mm shells or 4.6 torpedoes
   Stability (Unstable if below 1.00): 1.28
   Metacentric height 2.2 ft / 0.7 m
   Roll period: 12.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.01
   Seaboat quality  (Average = 1.00): 1.54

Hull form characteristics:
   Hull has low forecastle, rise forward of midbreak, low quarterdeck ,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.650 / 0.654
   Length to Beam Ratio: 6.92 : 1
   'Natural speed' for length: 17.18 kts
   Power going to wave formation at top speed: 21 %
   Trim (Max stability = 0, Max steadiness = 100): 46
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 1.00 ft / 0.30 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  16.73 ft / 5.10 m,  12.80 ft / 3.90 m
      - Forward deck:   30.00 %,  20.67 ft / 6.30 m,  20.67 ft / 6.30 m
      - Aft deck:   30.00 %,  12.80 ft / 3.90 m,  12.80 ft / 3.90 m
      - Quarter deck:   20.00 %,  4.92 ft / 1.50 m,  4.92 ft / 1.50 m
      - Average freeboard:      13.90 ft / 4.24 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 26.8 %
      - Above water (accommodation/working, high = better): 284.7 %
   Waterplane Area: 9,648 Square feet or 896 Square metres
   Displacement factor (Displacement / loading): 217 %
   Structure weight / hull surface area: 49 lbs/sq ft or 238 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.93
      - Longitudinal: 1.78
      - Overall: 1.00
   Excellent 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

[The Rock Doctor]

I took the 1931 A-class torpedo-boat, updated the machinery, and added a hypothetical transom stern.  I recognize it's too soon for the stern, but wanted to see how it affected the rest of the design.

And the answer is, I need almost a full knot more speed to keep the machinery percentage at 50%, which knocks down the seakeeping and also costs much of the A-class's weight reserve.

So on that basis, I'd actually have to say it does not help me here.  I was happy with the A-class' 33.1 knots as it was.


Enter ship name, Enter country Enter ship type laid down 1933

Displacement:
   2,152 t light; 2,280 t standard; 2,603 t normal; 2,862 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (406.35 ft / 393.70 ft) x 37.40 ft x (15.09 / 16.06 ft)
   (123.86 m / 120.00 m) x 11.40 m  x (4.60 / 4.90 m)

Armament:
      4 - 5.12" / 130 mm 45.0 cal guns - 67.61lbs / 30.67kg shells, 400 per gun
     Dual purpose guns in deck and hoist mounts, 1933 Model
     4 x Single mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
      4 - 1.97" / 50.0 mm 60.0 cal guns - 4.18lbs / 1.89kg shells, 1,500 per gun
     Anti-air guns in deck mounts, 1933 Model
     2 x Twin mounts on sides, forward deck aft
      2 raised mounts
      8 - 0.59" / 15.0 mm 90.0 cal guns - 0.12lbs / 0.05kg shells, 4,000 per gun
     Machine guns in deck mounts, 1933 Model
     4 x Twin mounts on sides, evenly spread
      4 raised mounts
      Weight of broadside 288 lbs / 131 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.18" / 30 mm   0.79" / 20 mm      1.18" / 30 mm
   2nd:   0.59" / 15 mm         -               -
   3rd:   0.59" / 15 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 50,604 shp / 37,750 Kw = 34.27 kts
   Range 5,500nm at 15.00 kts
   Bunker at max displacement = 582 tons

Complement:
   181 - 236

Cost:
   £1.348 million / $5.392 million

Distribution of weights at normal displacement:
   Armament: 83 tons, 3.2 %
      - Guns: 83 tons, 3.2 %
   Armour: 28 tons, 1.1 %
      - Armament: 28 tons, 1.1 %
   Machinery: 1,303 tons, 50.1 %
   Hull, fittings & equipment: 608 tons, 23.4 %
   Fuel, ammunition & stores: 451 tons, 17.3 %
   Miscellaneous weights: 129 tons, 5.0 %
      - Hull below water: 25 tons
      - On freeboard deck: 50 tons
      - Above deck: 54 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     619 lbs / 281 Kg = 9.2 x 5.1 " / 130 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.16
   Metacentric height 1.5 ft / 0.5 m
   Roll period: 12.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 60 %
         - Recoil effect (Restricted arc if above 1.00): 0.40
   Seaboat quality  (Average = 1.00): 0.93

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and small transom stern
   Block coefficient (normal/deep): 0.410 / 0.423
   Length to Beam Ratio: 10.53 : 1
   'Natural speed' for length: 21.38 kts
   Power going to wave formation at top speed: 65 %
   Trim (Max stability = 0, Max steadiness = 100): 65
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 3.94 ft / 1.20 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  23.95 ft / 7.30 m,  19.03 ft / 5.80 m
      - Forward deck:   25.00 %,  19.03 ft / 5.80 m,  19.03 ft / 5.80 m
      - Aft deck:   40.00 %,  11.15 ft / 3.40 m,  11.15 ft / 3.40 m
      - Quarter deck:   15.00 %,  11.15 ft / 3.40 m,  11.15 ft / 3.40 m
      - Average freeboard:      15.09 ft / 4.60 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 174.6 %
      - Above water (accommodation/working, high = better): 139.2 %
   Waterplane Area: 9,327 Square feet or 866 Square metres
   Displacement factor (Displacement / loading): 77 %
   Structure weight / hull surface area: 37 lbs/sq ft or 181 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.38
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

[Jefgte]

...And the answer is, I need almost a full knot more speed to keep the machinery percentage at 50%, which knocks down the seakeeping and also costs much of the A-class's weight reserve.

So on that basis, I'd actually have to say it does not help me here.  I was happy with the A-class' 33.1 knots as it was.

I agree, seakeeping is more important.

[Kaiser Kirk]

The 50% rule has long been a problem with seakeeping.
It's an issue Foxy raised, and he had a valid point, but it makes for workable DDs with not a great ability to exploit.
Never had the time to explore alternatives. 

Replacing DD engines makes the rebuild close to non-viable costwise,
How many knots would you loose stepping down to 0.75 comp hull and becoming a cruiser?

[The Rock Doctor]

The seakeeping is not a huge issue for me - it's a destroyer, 0.93 really ought to be good.  I'm more cranky about the weight cost, really.

[The Rock Doctor]

The 1933 light cruiser improves on the Mulde mainly in terms of bunkerage and the fitting of a Huelsmeyer device, although the secondary battery is now a dedicated AA set-up.


Enter ship name, Enter country Enter ship type laid down 1933

Displacement:
    8,647 t light; 9,083 t standard; 10,094 t normal; 10,903 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
    (605.26 ft / 590.55 ft) x 58.73 ft x (22.64 / 23.92 ft)
    (184.48 m / 180.00 m) x 17.90 m  x (6.90 / 7.29 m)

Armament:
      8 - 5.91" / 150 mm 50.0 cal guns - 121.25lbs / 55.00kg shells, 250 per gun
      Breech loading guns in turret on barbette mounts, 1933 Model
      4 x 2-gun mounts on centreline ends, evenly spread
        2 raised mounts - superfiring
      8 - 3.94" / 100 mm 45.0 cal guns - 30.78lbs / 13.96kg shells, 400 per gun
      Anti-air guns in deck mounts, 1933 Model
      4 x Twin mounts on side ends, evenly spread
      12 - 1.97" / 50.0 mm 60.0 cal guns - 4.19lbs / 1.90kg shells, 1,500 per gun
      Anti-air guns in deck mounts, 1933 Model
      6 x Twin mounts on sides, evenly spread
      8 - 0.59" / 15.0 mm 90.0 cal guns - 0.11lbs / 0.05kg shells, 5,000 per gun
      Machine guns in deck mounts, 1933 Model
      4 x Twin mounts on sides, evenly spread
        4 raised mounts
      Weight of broadside 1,267 lbs / 575 kg

Armour:
  - Belts:        Width (max)    Length (avg)        Height (avg)
    Main:    3.94" / 100 mm    383.86 ft / 117.00 m    16.37 ft / 4.99 m
    Ends:    Unarmoured
      Main Belt covers 100 % of normal length
      Main Belt inclined 16.00 degrees (positive = in)

  - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    5.91" / 150 mm    1.97" / 50 mm        3.94" / 100 mm
    2nd:    0.79" / 20 mm    0.59" / 15 mm              -
    3rd:    0.59" / 15 mm          -                  -
    4th:    0.59" / 15 mm          -                  -

  - Armoured deck - single deck:
    For and Aft decks: 1.97" / 50 mm
    Forecastle: 1.97" / 50 mm  Quarter deck: 1.97" / 50 mm

  - Conning towers: Forward 3.94" / 100 mm, Aft 0.00" / 0 mm

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 2 shafts, 84,450 shp / 63,000 Kw = 32.14 kts
    Range 8,000nm at 15.00 kts
    Bunker at max displacement = 1,820 tons

Complement:
    503 - 654

Cost:
    £3.568 million / $14.273 million

Distribution of weights at normal displacement:
    Armament: 328 tons, 3.2 %
      - Guns: 328 tons, 3.2 %
    Armour: 2,144 tons, 21.2 %
      - Belts: 1,008 tons, 10.0 %
      - Armament: 284 tons, 2.8 %
      - Armour Deck: 812 tons, 8.0 %
      - Conning Tower: 40 tons, 0.4 %
    Machinery: 2,461 tons, 24.4 %
    Hull, fittings & equipment: 3,422 tons, 33.9 %
    Fuel, ammunition & stores: 1,447 tons, 14.3 %
    Miscellaneous weights: 293 tons, 2.9 %
      - On freeboard deck: 103 tons
      - Above deck: 190 tons

Fittings:
-33 t:  1924 Fire Control (AD)
-25 t:  L/R wireless (AD)
-25 t:  Night-fighting doodads (AD)
-25 t:  Huelsmeyer device (AD)
-50 t:  Command facilities (AD)
-55 t:  2 armed floatplanes and one catapult with hangers aside aft funnel (FD)
-32 t:  2x4 530mm torpedo carriages (no reloads) (FD)
-16 t + 32 t:  Weight reserve (AD/FD)

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      11,955 lbs / 5,423 Kg = 116.1 x 5.9 " / 150 mm shells or 1.7 torpedoes
    Stability (Unstable if below 1.00): 1.07
    Metacentric height 2.6 ft / 0.8 m
    Roll period: 15.3 seconds
    Steadiness    - As gun platform (Average = 50 %): 60 %
            - Recoil effect (Restricted arc if above 1.00): 0.36
    Seaboat quality  (Average = 1.00): 1.08

Hull form characteristics:
    Hull has rise forward of midbreak,
      a normal bow and a cruiser stern
    Block coefficient (normal/deep): 0.450 / 0.460
    Length to Beam Ratio: 10.06 : 1
    'Natural speed' for length: 24.30 kts
    Power going to wave formation at top speed: 55 %
    Trim (Max stability = 0, Max steadiness = 100): 56
    Bow angle (Positive = bow angles forward): 20.00 degrees
    Stern overhang: 4.92 ft / 1.50 m
    Freeboard (% = length of deck as a percentage of waterline length):
                Fore end,    Aft end
      - Forecastle:    20.00 %,  26.90 ft / 8.20 m,  21.65 ft / 6.60 m
      - Forward deck:    30.00 %,  21.65 ft / 6.60 m,  21.65 ft / 6.60 m
      - Aft deck:    35.00 %,  13.78 ft / 4.20 m,  13.78 ft / 4.20 m
      - Quarter deck:    15.00 %,  13.78 ft / 4.20 m,  13.78 ft / 4.20 m
      - Average freeboard:        18.14 ft / 5.53 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 91.0 %
        - Above water (accommodation/working, high = better): 145.9 %
    Waterplane Area: 22,122 Square feet or 2,055 Square metres
    Displacement factor (Displacement / loading): 120 %
    Structure weight / hull surface area: 99 lbs/sq ft or 484 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0.96
        - Longitudinal: 1.33
        - Overall: 1.00
    Adequate machinery, storage, compartmentation space
    Excellent accommodation and workspace room


m

[Jefgte]

Classic and efficient.

[The Rock Doctor]

That's me with the mundane 4x2 designs around here.

[Kaiser Kirk]

I rather like the 4x2. I like the 2x3+2x2 better... but this go round I promised my self to do 4-gun.
The advantage of that is my more recent designs are 8-guns, but 'B' and 'X' are now secondary DP mounts,
adding to wing mounts for good all-round secondary arcs.

A 2-gun 150mm even with that armor may fall within the reasonable rotating weight range for a M&H, which would then allow slipping the BC lower, getting the light tonnage under 8000, and so freeing up the 0.9 hull,
which would allow a thicker belt.

I note 55 tons for 2 armed floatplanes, a catapult..and hangers. When I'm specifying hangers I add a little (5t) weight per plane. Otherwise I figure they ride on the catapult exposed in the weather.

[The Rock Doctor]

The planes themselves aren't more than 2 or 3 tonnes apiece, so I'm counting hanger weight as part of the 25 t per aircraft.