Re: Netherlands design study for 1921 program

[damocles]

RFS Vam Huys, Holland Torpedokruizer  laid down 1921

Displacement:
   5,997 t light; 6,232 t standard; 6,868 t normal; 7,376 t full load

Dimensions: Length overall / water x beam x draught
   550.03 ft / 550.03 ft x 50.03 ft x 19.03 ft (normal load)
   167.65 m / 167.65 m x 15.25 m  x 5.80 m

Armament:
     10 - 5.91" / 150 mm guns (5x2 guns), 102.98lbs / 46.71kg shells, 1915 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, majority aft, 2 raised mounts - superfiring
     8 - 2.95" / 75.0 mm guns (4x2 guns), 12.87lbs / 5.84kg shells, 1915 Model
     Quick firing guns in deck mounts with hoists
     on side, evenly spread
     8 - 0.59" / 15.0 mm guns (4x2 guns), 0.10lbs / 0.05kg shells, 1921 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 1,134 lbs / 514 kg
   Shells per gun, main battery: 150
   8 - 24.0" / 610 mm above water torpedoes

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.94" / 100 mm   440.12 ft / 134.15 m   10.66 ft / 3.25 m
   Ends:   Unarmoured
     Main Belt covers 123 % of normal length

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.95" / 75 mm   1.97" / 50 mm      1.97" / 50 mm
   2nd:   0.98" / 25 mm   0.39" / 10 mm      0.39" / 10 mm

  - Armour deck: 0.98" / 25 mm, Conning tower: 2.95" / 75 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 51,637 shp / 38,521 Kw = 30.00 kts
   Range 9,000nm at 12.00 kts
   Bunker at max displacement = 1,143 tons

Complement:
   376 - 490

Cost:
   £1.471 million / $5.884 million

Distribution of weights at normal displacement:
   Armament: 142 tons, 2.1 %
   Armour: 1,193 tons, 17.4 %
      - Belts: 740 tons, 10.8 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 107 tons, 1.6 %
      - Armour Deck: 322 tons, 4.7 %
      - Conning Tower: 23 tons, 0.3 %
   Machinery: 1,778 tons, 25.9 %
   Hull, fittings & equipment: 2,485 tons, 36.2 %
   Fuel, ammunition & stores: 870 tons, 12.7 %
   Miscellaneous weights: 400 tons, 5.8 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,306 lbs / 2,860 Kg = 61.2 x 5.9 " / 150 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.02
   Metacentric height 1.8 ft / 0.6 m
   Roll period: 15.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 72 %
         - Recoil effect (Restricted arc if above 1.00): 0.55
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has low quarterdeck
   Block coefficient: 0.459
   Length to Beam Ratio: 10.99 : 1
   'Natural speed' for length: 23.45 kts
   Power going to wave formation at top speed: 52 %
   Trim (Max stability = 0, Max steadiness = 100): 72
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19.00 ft / 5.79 m
      - Forecastle (20 %):   16.01 ft / 4.88 m
      - Mid (50 %):      14.01 ft / 4.27 m
      - Quarterdeck (15 %):   12.99 ft / 3.96 m (14.01 ft / 4.27 m before break)
      - Stern:      0.00 ft / 0.00 m
      - Average freeboard:   13.82 ft / 4.21 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 106.5 %
      - Above water (accommodation/working, high = better): 95.7 %
   Waterplane Area: 17,685 Square feet or 1,643 Square metres
   Displacement factor (Displacement / loading): 109 %
   Structure weight / hull surface area: 88 lbs/sq ft or 429 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1.00
      - Longitudinal: 1.00
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate
   Ship has slow, easy roll, a good, steady gun platform

400 tons misc..
100 tons fore control;
25 toins radar
25 tons radio
25 tons acoustics
32 tons torpedoes
100 tons mines

=========================================================

A heavy escort I intend for frigates for the battle fleet.

[Sachmle]

- Stern:      0.00 ft / 0.00 m

I think you may need a stern

Stability (Unstable if below 1.00): 1.02

We usually try for a minimum of 1.10, or at least most of us do. You'll probably have to trim down to get it, which would cost you your 72% steadiness/Slow, easy roll, good steady gun platform rating, but since torps are the main weapon on this ship that should be fine and you'll probably still be in the high 50s low 60s anyway. You could drop 1 2x15cm aft and see if having 4x2 instead of 5x2 makes this any better.

Main:   3.94" / 100 mm   440.12 ft / 134.15 m   10.66 ft / 3.25 m

Overkill. 75mm is more than enough against other 15cm/5.9" to 20cm/7.9" cruisers and anything bigger is not what this should be getting shot at by unless it's on a torpedo attack.

167.65 m / 167.65 m x 15.25 m  x 5.80 m

Since you're only 2.35m short of the MAX for a type 2 slip (170m) you may as well push it to the edge. The extra length may help with the stability too.

Other than that a very nice jack-of-all-trades Cruiser. Enough firepower to repel DDs and a lot of smaller CLs on it's own, but still hurt some of the bigger CL/CAs/Mini-BCs. Great torpedo load for dealing with anything bigger. Fast enough though not great in the speed dept. The mines will be a nasty surprise. I like it. I would try to make it 32kts but that's me and I'm next door to Speedy Gonzalez and you're not so I have different issues.

[TexanCowboy]

Don't you know? It's a exit for the new Dutch secret agent James Bond!

[damocles]

- Stern:      0.00 ft / 0.00 m

I think you may need a stern

Stability (Unstable if below 1.00): 1.02

We usually try for a minimum of 1.10, or at least most of us do. You'll probably have to trim down to get it, which would cost you your 72% steadiness/Slow, easy roll, good steady gun platform rating, but since torps are the main weapon on this ship that should be fine and you'll probably still be in the high 50s low 60s anyway. You could drop 1 2x15cm aft and see if having 4x2 instead of 5x2 makes this any better.

Main:   3.94" / 100 mm   440.12 ft / 134.15 m   10.66 ft / 3.25 m

Overkill. 75mm is more than enough against other 15cm/5.9" to 20cm/7.9" cruisers and anything bigger is not what this should be getting shot at by unless it's on a torpedo attack.

167.65 m / 167.65 m x 15.25 m  x 5.80 m

Since you're only 2.35m short of the MAX for a type 2 slip (170m) you may as well push it to the edge. The extra length may help with the stability too.

Other than that a very nice jack-of-all-trades Cruiser. Enough firepower to repel DDs and a lot of smaller CLs on it's own, but still hurt some of the bigger CL/CAs/Mini-BCs. Great torpedo load for dealing with anything bigger. Fast enough though not great in the speed dept. The mines will be a nasty surprise. I like it. I would try to make it 32kts but that's me and I'm next door to Speedy Gonzalez and you're not so I have different issues.

RFS Vam Huys, Holland Torpedokuizer  laid down 1921

Displacement:
   5,997 t light; 6,232 t standard; 6,868 t normal; 7,376 t full load

Dimensions: Length overall / water x beam x draught
   550.03 ft / 550.03 ft x 50.03 ft x 19.03 ft (normal load)
   167.65 m / 167.65 m x 15.25 m  x 5.80 m

Armament:
      10 - 5.91" / 150 mm guns (5x2 guns), 102.98lbs / 46.71kg shells, 1915 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, majority aft, 2 raised mounts - superfiring
      8 - 2.95" / 75.0 mm guns (4x2 guns), 12.87lbs / 5.84kg shells, 1915 Model
     Quick firing guns in deck mounts with hoists
     on side, evenly spread
      8 - 0.59" / 15.0 mm guns (4x2 guns), 0.10lbs / 0.05kg shells, 1921 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 1,134 lbs / 514 kg
   Shells per gun, main battery: 150
   8 - 24.0" / 610 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.94" / 100 mm   440.12 ft / 134.15 m   10.66 ft / 3.25 m
   Ends:   Unarmoured
     Main Belt covers 123 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.95" / 75 mm   1.97" / 50 mm      1.97" / 50 mm
   2nd:   0.98" / 25 mm   0.39" / 10 mm      0.39" / 10 mm

   - Armour deck: 0.98" / 25 mm, Conning tower: 2.95" / 75 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 51,637 shp / 38,521 Kw = 30.00 kts
   Range 9,000nm at 12.00 kts
   Bunker at max displacement = 1,143 tons

Complement:
   376 - 490

Cost:
   £1.471 million / $5.884 million

Distribution of weights at normal displacement:
   Armament: 142 tons, 2.1 %
   Armour: 1,193 tons, 17.4 %
      - Belts: 740 tons, 10.8 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 107 tons, 1.6 %
      - Armour Deck: 322 tons, 4.7 %
      - Conning Tower: 23 tons, 0.3 %
   Machinery: 1,778 tons, 25.9 %
   Hull, fittings & equipment: 2,510 tons, 36.6 %
   Fuel, ammunition & stores: 870 tons, 12.7 %
   Miscellaneous weights: 375 tons, 5.5 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,313 lbs / 2,863 Kg = 61.3 x 5.9 " / 150 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.01
   Metacentric height 1.8 ft / 0.5 m
   Roll period: 15.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 77 %
         - Recoil effect (Restricted arc if above 1.00): 0.58
   Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
   Hull has low quarterdeck
   Block coefficient: 0.459
   Length to Beam Ratio: 10.99 : 1
   'Natural speed' for length: 23.45 kts
   Power going to wave formation at top speed: 52 %
   Trim (Max stability = 0, Max steadiness = 100): 72
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19.00 ft / 5.79 m
      - Forecastle (20 %):   16.01 ft / 4.88 m
      - Mid (50 %):      14.01 ft / 4.27 m
      - Quarterdeck (15 %):   12.99 ft / 3.96 m (14.01 ft / 4.27 m before break)
      - Stern:      14.01 ft / 4.27 m
      - Average freeboard:   14.87 ft / 4.53 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 106.1 %
      - Above water (accommodation/working, high = better): 95.7 %
   Waterplane Area: 17,685 Square feet or 1,643 Square metres
   Displacement factor (Displacement / loading): 110 %
   Structure weight / hull surface area: 87 lbs/sq ft or 426 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.99
      - Longitudinal: 1.08
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate
   Ship has slow, easy roll, a good, steady gun platform

375 tons misc..
100 tons fire control;
25 tons radar
25 tons radio
25 tons acoustics
32 tons torpedoes
100 tons mines
============================================
Fixed the stern.

Some notes on what I'm trying to do.

1. I'm trying to develop a class of hulls that can take mixes of armament and equipment over time. Eventually I am going to refit a lot of these tubs to meet future threats and try to save money on block obsolescence so I look to future developments I have in progress that I will mid-life upgrade into the ships.
2. The tonnage adjustments are very tricky. Since I will be building light cruisers to fill that hole in my fleet, I need to pack as much of a punch for the least dollar spent. Close enough for a tyro like me at Springsharp is better than not good enough.
3.  A block speed of ~ 28-30 knots seems to be what Korpen selected as the speed band.  Its okay. I won't be able to catch some of the faster guys with this limit, but then again, they have the money for speed, and I don't. A knot is not that significant, if I can add a couple of guns, some armor and range. 
4. Torpedoes versus guns. For ships this small (<7,000 tons), with the limited guns tonnage and armor I can squeeze in: torpedoes just make more sense. They won't last long in a gunfight and they will usually be outgunned vt enemy cruisers, so they better carry something that makes them a threat.
5. Mines are the staple weapon of the weak guy. I don't have fast mine-layers that can lay ambush minefields in a naval war to catch a fleet that chases me. (a curious Korpen omission). Voila.

D.
5.           
   
   

[Logi]

Stability (Unstable if below 1.00): 1.01

Might need to fix that.

4. Torpedoes versus guns. For ships this small (<7,000 tons), with the limited guns tonnage and armor I can squeeze in: torpedoes just make more sense. They won't last long in a gunfight and they will usually be outgunned vt enemy cruisers, so they better carry something that makes them a threat.

Actually 10 6" guns is quite more armed than other cruisers. I know, I design my ships to be overarmed (but then again, I have 1 more pair of 6" on my CL21 than you...

5. Mines are the staple weapon of the weak guy. I don't have fast mine-layers that can lay ambush minefields in a naval war to catch a fleet that chases me. (a curious Korpen omission). Voila.

Perhaps, but I would not want to be there when a stray shell hits the mines.

[damocles]

Stability (Unstable if below 1.00): 1.01

Might need to fix that.

Most of my designs are better in this department, here I needed the steady gun platform.  

4. Torpedoes versus guns. For ships this small (<7,000 tons), with the limited guns tonnage and armor I can squeeze in: torpedoes just make more sense. They won't last long in a gunfight and they will usually be outgunned vt enemy cruisers, so they better carry something that makes them a threat.

Actually 10 6" guns is quite more armed than other cruisers. I know, I design my ships to be overarmed (but then again, I have 1 more pair of 6" on my CL21 than you...

You also have one more torpedo, so I accept that you think along similar lines to what I see as the role of the light cruiser.  

5. Mines are the staple weapon of the weak guy. I don't have fast mine-layers that can lay ambush minefields in a naval war to catch a fleet that chases me. (a curious Korpen omission). Voila.

Perhaps, but I would not want to be there when a stray shell hits the mines.

[/quote]

How you use ambush minefields is what is important. The way I've read them used in this sim might not be the best way. I will leave it at that to say you may assume that it is a risk that I have means to handle.    

D.

Tweaked again.

RFS Vam Huys, Holland Torpedokuizer  laid down 1921

Displacement:
   5,980 t light; 6,216 t standard; 6,924 t normal; 7,490 t full load

Dimensions: Length overall / water x beam x draught
   557.74 ft / 557.74 ft x 50.03 ft (Bulges 50.85 ft) x 19.03 ft (normal load)
   170.00 m / 170.00 m x 15.25 m (Bulges 15.50 m)  x 5.80 m

Armament:
      10 - 5.91" / 150 mm guns (5x2 guns), 102.98lbs / 46.71kg shells, 1915 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, majority aft, 2 raised mounts - superfiring
      8 - 2.95" / 75.0 mm guns (4x2 guns), 12.87lbs / 5.84kg shells, 1915 Model
     Quick firing guns in deck mounts with hoists
     on side, evenly spread
      8 - 0.59" / 15.0 mm guns (4x2 guns), 0.10lbs / 0.05kg shells, 1921 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 1,134 lbs / 514 kg
   Shells per gun, main battery: 150
   8 - 24.0" / 610 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.94" / 100 mm   381.92 ft / 116.41 m   10.66 ft / 3.25 m
   Ends:   Unarmoured
     Main Belt covers 105 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.95" / 75 mm   1.97" / 50 mm      1.97" / 50 mm
   2nd:   0.98" / 25 mm   0.39" / 10 mm      0.39" / 10 mm

   - Armour deck: 0.98" / 25 mm, Conning tower: 2.95" / 75 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 51,434 shp / 38,369 Kw = 30.00 kts
   Range 10,000nm at 12.00 kts
   Bunker at max displacement = 1,274 tons

Complement:
   379 - 493

Cost:
   £1.467 million / $5.868 million

Distribution of weights at normal displacement:
   Armament: 142 tons, 2.0 %
   Armour: 1,109 tons, 16.0 %
      - Belts: 655 tons, 9.5 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 107 tons, 1.6 %
      - Armour Deck: 324 tons, 4.7 %
      - Conning Tower: 23 tons, 0.3 %
   Machinery: 1,771 tons, 25.6 %
   Hull, fittings & equipment: 2,558 tons, 36.9 %
   Fuel, ammunition & stores: 943 tons, 13.6 %
   Miscellaneous weights: 400 tons, 5.8 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,614 lbs / 3,000 Kg = 64.2 x 5.9 " / 150 mm shells or 1.2 torpedoes
   Stability (Unstable if below 1.00): 1.07
   Metacentric height 2.0 ft / 0.6 m
   Roll period: 15.0 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.49
   Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.449
   Length to Beam Ratio: 10.97 : 1
   'Natural speed' for length: 23.62 kts
   Power going to wave formation at top speed: 51 %
   Trim (Max stability = 0, Max steadiness = 100): 65
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18.86 ft / 5.75 m
      - Forecastle (20 %):   15.91 ft / 4.85 m
      - Mid (40 %):      13.94 ft / 4.25 m
      - Quarterdeck (15 %):   13.94 ft / 4.25 m
      - Stern:      13.94 ft / 4.25 m
      - Average freeboard:   14.77 ft / 4.50 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 105.3 %
      - Above water (accommodation/working, high = better): 94.4 %
   Waterplane Area: 17,785 Square feet or 1,652 Square metres
   Displacement factor (Displacement / loading): 112 %
   Structure weight / hull surface area: 88 lbs/sq ft or 430 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1.00
      - Longitudinal: 1.06
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate
   Ship has slow, easy roll, a good, steady gun platform

375 tons misc..
100 tons fire control;
25 toins radar
25 tons radio
25 tons acoustics
32 tons torpedoes
100 tons mines

[The Rock Doctor]

Your predecessor operated a couple of "sloops" with the idea that minefields would be laid during a retreat, with the enemy ships advancing into the minefield to their detriment.  This made little sense to me - the Dutch ships could do little more than lay a single line, which if parallel to the enemy's course, is extremely unlikely to be struck.

[damocles]

Your predecessor operated a couple of "sloops" with the idea that minefields would be laid during a retreat, with the enemy ships advancing into the minefield to their detriment.  This made little sense to me - the Dutch ships could do little more than lay a single line, which if parallel to the enemy's course, is extremely unlikely to be struck.

Huh? That is not how you lay ambush minefields.

My predecessor must have tried to use his minelayers differently, then.  I could go into detail about fishscale or herring bone pattern fields, as opposed to random or diamond fields  or why the fields are laid as a terrain feature and not as some static torpedo that the enemy will obligingly run into as he stern chases.

In general terms, the minefield is something you use in addition to the gun and torpedo in your maneuver plan, not something you dumped over the stern into the path of a pursuing enemy as he chases you in mid battle. The reason for the fast mine-layer is exactly that actual use, to lay minefields QUICKLY before an impending battle as the means to channel an enemy into your kill boxes. Its to restrict his movement in a prepared ambush, not a magic escape gimmick. You have to prepare these fields before the battle, not during or he can dodge the fields. If you are short on time, you better have more than two sloops working, and the ships better be FAST well armed mine-layers as they will have to fight as soon as the enemy enters the battle-space.

D.       

[TexanCowboy]

Ok, 1.01 stability means that a few hits below the waterline from a 6-7'' shell is going to cause the ship to have to counterflood, reducing speed. That's not what you really want...

Also, I don't think we can have 24'' torpedoes at that point in time....

[Sachmle]

Also, I don't think we can have 24'' torpedoes at that point in time....

1918: (+8) 20000@26, 15000@30, 10000@35, 300kg warhead (+2) 3t weight, 24"

RFS Vam Huys, Holland Torpedokuizer  laid down 1921

11. 1918: (+8) 20000@26, 15000@30, 10000@35, 300kg warhead (+2) 3t weight, 24" (1/6) NEW.

[Nobody]

Also, I don't think we can have 24'' torpedoes at that point in time....

Ok, they don't show up before the 1918 tech, but OTL 600 mm became common during WW1 with even larger ones were planned (which means I wouldn't mind them in the 1913 tech).

[damocles]

Ok, 1.01 stability means that a few hits below the waterline from a 6-7'' shell is going to cause the ship to have to counterflood, reducing speed. That's not what you really want...

Also, I don't think we can have 24'' torpedoes at that point in time....

1. I now have 1.07 stability for this ship.
2. I'm working on the 1918 torpedoes as fast as I can. See title for cruiser laydown dates. The torpedoes will be ready 1922/1923. I expect the cruisers won't be ready for fit-out before the torpedoes are available as I expect they will take at least two years to build in batches and they will be floated out and fitted out to clear docks and slips.

D.

 







 

[Sachmle]

Also, I don't think we can have 24'' torpedoes at that point in time....

Ok, they don't show up before the 1918 tech, but OTL 600 mm became common during WW1 with even larger ones were planned (which means I wouldn't mind them in the 1913 tech).

I know, I already asked about the H-8. :(

[Borys]

Ahoj!
I'm taking a breather from torpedo design, being happy with the OTL KM 50cm weapon. But My aim is this:
http://www.navweaps.com/Weapons/WTBR_PreWWII.htm
scroll to bottom ...

Borys

[Desertfox]

Good thing that I'm sticking mine sweeping gear on all my new ships.