Vilnius Union Ships, 1920+: Electric Drive Boogaloo

[Kaiser Kirk]

When I was trying to estimate the penetration for the Parthian ACs, one reason I developed the 255L47 was the numbers were working out to penetrate 150mm at 18km - basically once I see the hull, I can put holes in it.
As the range comes down the penetration ramps up quickly. With the improved AP caps, I expect even better performance.

-Considerations I'd have includes the historic short visibility ranges of the North Sea,
and that the Norse have historically deployed 250mm ACs.

That would suggest the lighter armors might not be appropriate for your home theater.

-The other side is the Romans , who's last AC style ship had 235mm and should have completed by 1922, so by now you should know it can make 32knots. Your naval engineers should be able to figure out the approximate weight in armor, and rough out the capabilities. So they have an outline of where the Romans are going.
Snip tends to push the speed to a point where his ships really can't be caught....it's kinda annoying.
But managing 35 knots to catch it would be difficult and really really expensive in tonnage.

-The Slow Mayan ships operated as a block and did not disperse much, plus they just don't have much trade to protect and were willing to let that be relatively undefended.

-Personally, I think if you are investing this much in a vessel, a TDS is advisable.

So...
Sim B : Not enough Belt for Norse
Sim C : Same
Sim D/E : Good armor, no TDS and 18.8 BP
Sim F : 22.7 BP, Good all round, but costs as much as a 15 year old dreadnaught. The TDS is thin, and likely reliable against aerial torps and mines, which might be enough.
Sim G : Unless all the guns are going to shoot forward as a 'chase' armanent, OR you're going to shorten the citadel and just accept the mild risk of the ends getting riddled and floatation loss.
Sim A : Only 1400 tons more than Sim F, much better TDS. Enough deck armor for longer range fights against pretty heavy ships, but 5500 tons heavier than the weakest.   
Sim H : Seems like the equivalent of what I call the Dahae class :) I would be curious if a 24000 ton version could have that 40mm TDS.

I've gone through a similar design process for my Zemaka follow ons, the Hamika and Wadsab classes, with the Dahae meant also to regularly engage the older BCs out there....all classes I'll be considering for a 1928 laydown :)

[The Rock Doctor]

On 24,000t, I can bump the TDS to 40mm, and do 90mm deck armor.  I shave off a 130mm mounting to accomplish that, but it's not a huge sacrifice.

[Kaiser Kirk]

The next question is the perceived tactical value of 31.89knts vs. 32
...
Or 33 or 31

The Roman cruisers you would know about would be ~30-31 knots.
Presumably the Norse are in that same ballpark. The Valkyrie class was 32knots.

Supposedly you need +2-3knots to actually count on hauling them in -
to offset the length of chase, age of boilers, hull fouling, etc.

So...33 to 34 knots to ensure the hunter roll.
One advantage of large ships is the longer length potentially
allows more speed....
Or
31 to match the Romans but ensure the Norse can't reliably get away.
Does that 0.89knts buy much? Does it cost much?
Or 32 to at least nominally match the Norse.

[TacCovert4]

I would also go with the 250mm gun over the 300.  The reason that the follow on to the R Class is the Uhlan Class....is that the 6x280 is really just not as good as 9 x 240.  Ultimately the small bit of extra punch you're getting out of the bigger gun is compensated for by the slightly faster RoF, and greater number of tubes.  8 is really the lower edge of optimum for ladder shooting, hence I've gotten in the habit of aiming for 8+ guns on everything, including DDs when possible.  If you're going to stay sub-20k, use the 250 and put some tonnage into protection, like Kirk said a TDS is basically a requirement at this point for any ship that size.  If you're going to go up to 24k, you can get 8 x 300, at which time your Razee is functionally on par with any number of battlecruisers afloat, so that may be worth it to go for the bigger design.

[Kaiser Kirk]

Building on what Tac said, while I have the 300L41.5 which I could put to the same use, but decided my 255L47 was lighter and could do the job at all ranges I needed. If it can see a cruiser, it can kill that cruiser.
For the Dahae series I am looking at either my 333L43.  I've looked at  300/333/345/365s for these 'heavy armored cruisers'

[The Rock Doctor]

It's probably time to restart coastal minesweeper production soon.

This is a modest update of the previous 1923 iteration.  We're trying out diesel-electric machinery for responsive handling in minefields, and I've allocated more tonnage to both the primary sweeping and secondary ASW function.  The type also remains able to plop a small minefield of its own into the water if that proves useful.

Enter ship name, Enter country Enter ship type laid down 1928

Displacement:
   366 t light; 378 t standard; 398 t normal; 415 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (160.89 ft / 154.20 ft) x 26.25 ft x (6.89 / 7.10 ft)
   (49.04 m / 47.00 m) x 8.00 m  x (2.10 / 2.17 m)

Armament:
      1 - 2.95" / 75.0 mm 45.0 cal gun - 12.98lbs / 5.89kg shells, 250 per gun
     Quick firing gun in deck mount, 1928 Model
     1 x Single mount on centreline, forward deck centre
      1 raised mount
      1 - 1.97" / 50.0 mm 45.0 cal gun - 3.85lbs / 1.74kg shells, 250 per gun
     Anti-air gun in deck mount, 1928 Model
     1 x Single mount on centreline, aft deck forward
      1 raised mount
      4 - 0.59" / 15.0 mm 90.0 cal guns - 0.12lbs / 0.05kg shells, 4,000 per gun
     Machine guns in deck mounts, 1928 Model
     2 x Twin mounts on sides, forward deck aft
      2 raised mounts
      Weight of broadside 17 lbs / 8 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.79" / 20 mm   0.12" / 3 mm            -
   2nd:   0.79" / 20 mm   0.12" / 3 mm            -
   3rd:   0.59" / 15 mm         -               -

Machinery:
   Diesel Internal combustion generators,
   Electric motors, 2 shafts, 1,609 shp / 1,200 Kw = 16.78 kts
   Range 2,500nm at 10.00 kts
   Bunker at max displacement = 37 tons

Complement:
   43 - 57

Cost:
   £0.080 million / $0.319 million

Distribution of weights at normal displacement:
   Armament: 4 tons, 0.9 %
   Armour: 4 tons, 0.9 %
      - Armament: 4 tons, 0.9 %
   Machinery: 50 tons, 12.6 %
   Hull, fittings & equipment: 158 tons, 39.6 %
   Fuel, ammunition & stores: 32 tons, 8.1 %
   Miscellaneous weights: 151 tons, 37.9 %
      - Hull below water: 43 tons
      - On freeboard deck: 102 tons
      - Above deck: 6 tons

Fittings:
-15 t:  Enhanced hydrophone package (BW)
-28 t:  Diesel-electric drive (BW)
-50 t:  Sweeping gear (FD)
-40 t:  Mine capacity (FD)
-8 t:  ASW weaponry (FD)
-1 t:  1918 fire control (AD)
-5 t:  Nightfighting doodads (AD)
-4 t:  Weight reserve

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     1,236 lbs / 561 Kg = 96.0 x 3.0 " / 75 mm shells or 0.9 torpedoes
   Stability (Unstable if below 1.00): 1.28
   Metacentric height 1.0 ft / 0.3 m
   Roll period: 10.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.05
   Seaboat quality  (Average = 1.00): 1.92

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.500 / 0.505
   Length to Beam Ratio: 5.88 : 1
   'Natural speed' for length: 12.42 kts
   Power going to wave formation at top speed: 62 %
   Trim (Max stability = 0, Max steadiness = 100): 26
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  19.36 ft / 5.90 m,  16.40 ft / 5.00 m
      - Forward deck:   20.00 %,  16.40 ft / 5.00 m,  16.40 ft / 5.00 m
      - Aft deck:   45.00 %,  8.53 ft / 2.60 m,  8.53 ft / 2.60 m
      - Quarter deck:   15.00 %,  8.53 ft / 2.60 m,  8.53 ft / 2.60 m
      - Average freeboard:      11.92 ft / 3.63 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 56.8 %
      - Above water (accommodation/working, high = better): 130.8 %
   Waterplane Area: 2,697 Square feet or 251 Square metres
   Displacement factor (Displacement / loading): 150 %
   Structure weight / hull surface area: 31 lbs/sq ft or 152 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.80
      - Longitudinal: 7.61
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is excellent
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Below water is 15 for EHP and 28 for diesel-electric

[Kaiser Kirk]

This is a modest update of the previous 1923 iteration.  We're trying out diesel-electric machinery for responsive handling in minefields, and I've allocated more tonnage to both the primary sweeping and secondary ASW function.  The type also remains able to plop a small minefield of its own into the water if that proves useful.

From a wargaming perspective,
depending on how generalized things are
it's probably good to specify the details of the ASW loadout.

-do you have stick bombs for your 75mm gun, so you can engage it as it tries to submerge?
-do you have Y throwers for a broader pattern
-are you going with lots of small DCs or a few larger ones (damage vs. destroy)

From a SIM perspective ...
-Generally, given ignorance about what's really needed- I've seen/ done
various implementations of MSW packages.
-2ts : light paravane
-5t : normal paravane.
<25t : limited MSW package
25t : full MSW package....whatever that is.

That doesn't mean you can't allocate 50t , just that if I'm trying to make a call I'm looking for 25 as 'full'.


If you want, you can dip under 1.0 hull in the cruiser archtype.
Most of my minesweepers don't due to both age and a desire for a strong hull.
Actually most of them have a bulge meant to be a double hull to keep from being crushed.


I'm currently trying to craft a 500 ton (6mo build) fleet ASW escort with dockside conversion options to MS / ML / Transport,
Your vessel works for that, though I'm trying to get 2knots more speed. Maybe I should take another look at 18knots.
I want something that can catch a surfaced sub, and my 1925 is 17knots, so +2-3 is 19-20.
Of course Subs have poor seakeeping so can't manage that speed except in good weather. Plus it would be loud.
Interesting, I'm struggling with

[The Rock Doctor]

If just 25 t is required for a full sweeping kit, maybe I'll re-sim a bit and see what I can do with speed as well.

Point taken on ASW stuff, and I know you've mentioned it before.

[The Rock Doctor]

Same miscellaneous weight allocation as above, except the weight reserve is now 4 t and the D-E machinery is 37 t.

Enter ship name, Enter country Enter ship type laid down 1928

Displacement:
   366 t light; 378 t standard; 398 t normal; 415 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (160.89 ft / 154.20 ft) x 26.25 ft x (6.89 / 7.10 ft)
   (49.04 m / 47.00 m) x 8.00 m  x (2.10 / 2.17 m)

Armament:
      1 - 2.95" / 75.0 mm 45.0 cal gun - 12.98lbs / 5.89kg shells, 250 per gun
     Quick firing gun in deck mount, 1928 Model
     1 x Single mount on centreline, forward deck centre
      1 raised mount
      1 - 1.97" / 50.0 mm 45.0 cal gun - 3.85lbs / 1.75kg shells, 250 per gun
     Anti-air gun in deck mount, 1928 Model
     1 x Single mount on centreline, aft deck forward
      1 raised mount
      4 - 0.59" / 15.0 mm 90.0 cal guns - 0.12lbs / 0.05kg shells, 4,000 per gun
     Machine guns in deck mounts, 1928 Model
     2 x Twin mounts on sides, forward deck aft
      2 raised mounts
      Weight of broadside 17 lbs / 8 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.79" / 20 mm   0.12" / 3 mm            -
   2nd:   0.79" / 20 mm   0.12" / 3 mm            -
   3rd:   0.59" / 15 mm         -               -

Machinery:
   Diesel Internal combustion generators,
   Electric motors, 2 shafts, 2,144 shp / 1,600 Kw = 17.96 kts
   Range 2,500nm at 10.00 kts
   Bunker at max displacement = 37 tons

Complement:
   43 - 57

Cost:
   £0.089 million / $0.355 million

Distribution of weights at normal displacement:
   Armament: 4 tons, 0.9 %
   Armour: 4 tons, 0.9 %
      - Armament: 4 tons, 0.9 %
   Machinery: 67 tons, 16.8 %
   Hull, fittings & equipment: 159 tons, 39.9 %
   Fuel, ammunition & stores: 32 tons, 8.1 %
   Miscellaneous weights: 133 tons, 33.4 %
      - Hull below water: 52 tons
      - On freeboard deck: 75 tons
      - Above deck: 6 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     977 lbs / 443 Kg = 75.9 x 3.0 " / 75 mm shells or 0.7 torpedoes
   Stability (Unstable if below 1.00): 1.31
   Metacentric height 1.1 ft / 0.3 m
   Roll period: 10.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.05
   Seaboat quality  (Average = 1.00): 1.60

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.500 / 0.505
   Length to Beam Ratio: 5.88 : 1
   'Natural speed' for length: 12.42 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 31
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  19.36 ft / 5.90 m,  16.40 ft / 5.00 m
      - Forward deck:   20.00 %,  16.40 ft / 5.00 m,  16.40 ft / 5.00 m
      - Aft deck:   45.00 %,  8.53 ft / 2.60 m,  8.53 ft / 2.60 m
      - Quarter deck:   15.00 %,  8.53 ft / 2.60 m,  8.53 ft / 2.60 m
      - Average freeboard:      11.92 ft / 3.63 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 72.6 %
      - Above water (accommodation/working, high = better): 130.8 %
   Waterplane Area: 2,697 Square feet or 251 Square metres
   Displacement factor (Displacement / loading): 142 %
   Structure weight / hull surface area: 31 lbs/sq ft or 153 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.80
      - Longitudinal: 7.66
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is excellent
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

[Kaiser Kirk]

Nice little ship.
I like the extra speed, just a tad more than the best a surfaced sub can manage.

[Jefgte]

With 500t you can make a multifunctional ship.

[The Rock Doctor]

These guys can sweep or lay mines, support ASW work, do coastal convoys, and probably mundane stuff like search and rescue and customs inspections if really needed.  I feel they're multi-functional enough.

There's a need for a larger ocean-going escort/patrol platform and I could see something like the historical Algerine class being a basis for that.

[The Rock Doctor]

Note for self, Wikipedia reading suggests Americans went with diesel-electric drive in response to magnetic mines (one system to both propel the ship and energize anti-mine stuff), while British/Canadian designs relied on a range of whatever machinery was at hand, I guess.

[The Rock Doctor]

A (barely) mobile anti-aircraft battery for use in protecting coastal assets - ports, slow convoys, amphibious operations.

In a desperate situation, the armament can be used at short-range in an anti-surface capacity, and there's the most basic of ASW equipment if that proves necessary.  But really it's just there to shoot at airplanes.

A box protects the machinery and bullets from enemy strafing, but obviously won't save the vessel from a serious pounding.


Enter ship name, Enter country Enter ship type laid down 1928

Displacement:
   207 t light; 225 t standard; 239 t normal; 249 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (150.24 ft / 144.36 ft) x 26.25 ft x (3.94 / 4.08 ft)
   (45.79 m / 44.00 m) x 8.00 m  x (1.20 / 1.24 m)

Armament:
      2 - 3.94" / 100.0 mm 45.0 cal guns - 30.77lbs / 13.96kg shells, 250 per gun
     Anti-air guns in deck mounts, 1928 Model
     2 x Single mounts on centreline ends, evenly spread
      4 - 1.97" / 50.0 mm 45.0 cal guns - 3.85lbs / 1.75kg shells, 500 per gun
     Anti-air guns in deck mounts, 1928 Model
     2 x Twin mounts on centreline ends, evenly spread
      2 raised mounts
      4 - 0.59" / 15.0 mm 90.0 cal guns - 0.12lbs / 0.05kg shells, 4,000 per gun
     Breech loading guns in deck mounts, 1928 Model
     2 x Twin mounts on sides, evenly spread
      2 raised mounts
      Weight of broadside 77 lbs / 35 kg

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

   - Box over machinery & magazines: 0.98" / 25 mm
   Forecastle: 0.98" / 25 mm  Quarter deck: 0.98" / 25 mm

   - Conning towers: Forward 0.98" / 25 mm,  Aft 0.00" / 0 mm

Machinery:
   Diesel Internal combustion generators,
   Electric motors, 1 shaft, 402 shp / 300 Kw = 12.50 kts
   Range 2,000nm at 10.00 kts
   Bunker at max displacement = 24 tons

Complement:
   29 - 39

Cost:
   £0.050 million / $0.199 million

Distribution of weights at normal displacement:
   Armament: 15 tons, 6.1 %
   Armour: 50 tons, 21.0 %
      - Armament: 18 tons, 7.5 %
      - Armour Deck: 31 tons, 13.1 %
      - Conning Tower: 1 tons, 0.3 %
   Machinery: 13 tons, 5.2 %
   Hull, fittings & equipment: 105 tons, 44.2 %
   Fuel, ammunition & stores: 32 tons, 13.4 %
   Miscellaneous weights: 24 tons, 10.1 %
      - Hull below water: 12 tons
      - On freeboard deck: 8 tons
      - Above deck: 4 tons

Fittings:
-7t:  D-E machinery (BW)
-5t:  The basic hydrophone deal (BW)
-4 t:  A few depth charges (FD)
-4 t:  Weight reserve (FD)
-2 t:  Fire control (AD)
-2 t:  A searchlight or two (AD)

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     1,047 lbs / 475 Kg = 34.3 x 3.9 " / 100 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.22
   Metacentric height 1.0 ft / 0.3 m
   Roll period: 11.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 100 %
         - Recoil effect (Restricted arc if above 1.00): 0.41
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.560 / 0.564
   Length to Beam Ratio: 5.50 : 1
   'Natural speed' for length: 12.01 kts
   Power going to wave formation at top speed: 47 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  14.76 ft / 4.50 m,  11.81 ft / 3.60 m
      - Forward deck:   30.00 %,  11.81 ft / 3.60 m,  11.81 ft / 3.60 m
      - Aft deck:   35.00 %,  11.81 ft / 3.60 m,  11.81 ft / 3.60 m
      - Quarter deck:   15.00 %,  11.81 ft / 3.60 m,  11.81 ft / 3.60 m
      - Average freeboard:      12.05 ft / 3.67 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 44.1 %
      - Above water (accommodation/working, high = better): 201.2 %
   Waterplane Area: 2,593 Square feet or 241 Square metres
   Displacement factor (Displacement / loading): 173 %
   Structure weight / hull surface area: 25 lbs/sq ft or 120 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.58
      - Longitudinal: 8.10
      - Overall: 0.75
   Caution: Hull subject to strain in open-sea
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

[The Rock Doctor]

Pondering options for a larger carrier.

All would have 100mm belts, 50mm deck, and 32 knots.  Light displacement a tad under 15,000, and 24 x 1933 vintage aircraft

The main battery is the decision point:

A)  5x2 130mm in M&H; one at the stern, the other four at the corners

B)  2x2 150mm in T&B; one ahead and one behind the island

C)  2x2 150mm in T&B; a superfiring pair behind the island

B&C provide heavier guns for anti-surface defence, but put a big weight on the port side and probably cause some blast damage to the flight deck if fired dead astern or across.  Well, the non-superfiring guns.  Superfiring 150mm might be high enough to be safe, I dunno.

Note that I'm interpreting the location of the 150mm guns - in the location that the Essex class would have had some - as not requiring a flight-deck cruiser arrangement.  It "merely" takes up additional deck space on the port side.

Thoughts?