Next generation DD from Design Bureau Hamburg

[Tanthalas]

I favor something simple like double whatever SS reports as a ships Sea Keeping for TB/DD type ships.

Michael

I can accept a .5 minimum number for TB/DD Sea Keaping since that would give them a 1.0 if we considerd it doubled (and we generaly view 1.0 as the absolute minimum for every other ship type).

[Guinness]

We consider 1.0 to be minimum, but really it's probably average, and even a little lower is ok.

If some time turns up this weekend (my honey-do list is long apparently), I may sim a few OTL cruisers from sources I have to see just what SS thinks of their seakeeping.

But if we are looking for a guideline for DDs based on SS's seakeeping number, yeah multiplying it by two seems a serviceable method.

[maddox]

If a doubling is the solution, French DD's won't drop much lower than 1.5 (from .75). Call it a personal design quirk.

[Tanthalas]

If a doubling is the solution, French DD's won't drop much lower than 1.5 (from .75). Call it a personal design quirk.

I consider that compleatly acceptable, each nation has its own quirks as is I see no reason for that trend not to continue.  Rohan is holding around a .60 on my curent DD projects and I dont intend to go much lower (mostly because I cant figure out how to without trashing composite str.)

[ledeper]

WOW a sh#¤ load of Dd with a sea-keeping at 2.0, me like giggle :D :D

[ledeper]

An another try:
Enter ship name, Enter country Enter ship type laid down 1920

Displacement:
   1.464 t light; 1.523 t standard; 1.839 t normal; 2.091 t full load

Dimensions: Length overall / water x beam x draught
   393,67 ft / 390,42 ft x 42,65 ft x 10,17 ft (normal load)
   119,99 m / 119,00 m x 13,00 m  x 3,10 m

Armament:
     6 - 4,92" / 125 mm guns (3x2 guns), 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in deck mounts
     on centreline ends, majority forward, 1 raised mount - superfiring
     4 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,88kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 365 lbs / 166 kg
   Shells per gun, main battery: 110
   6 - 19,7" / 500 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 3 shafts, 29.551 shp / 22.045 Kw = 31,00 kts
   Range 850nm at 31,00 kts
   Bunker at max displacement = 568 tons

Complement:
   139 - 182

Cost:
   £0,495 million / $1,980 million

Distribution of weights at normal displacement:
   Armament: 46 tons, 2,5 %
   Machinery: 856 tons, 46,5 %
   Hull, fittings & equipment: 517 tons, 28,1 %
   Fuel, ammunition & stores: 375 tons, 20,4 %
   Miscellaneous weights: 45 tons, 2,4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     700 lbs / 318 Kg = 11,7 x 4,9 " / 125 mm shells or 0,4 torpedoes
   Stability (Unstable if below 1.00): 1,76
   Metacentric height 3,5 ft / 1,1 m
   Roll period: 9,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0,11
   Seaboat quality  (Average = 1.00): 1,01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,380
   Length to Beam Ratio: 9,15 : 1
   'Natural speed' for length: 19,76 kts
   Power going to wave formation at top speed: 60 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18,44 ft / 5,62 m
      - Forecastle (20 %):   13,85 ft / 4,22 m
      - Mid (50 %):      13,85 ft / 4,22 m
      - Quarterdeck (15 %):   13,85 ft / 4,22 m
      - Stern:      13,85 ft / 4,22 m
      - Average freeboard:   14,21 ft / 4,33 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 171,5 %
      - Above water (accommodation/working, high = better): 150,6 %
   Waterplane Area: 10.153 Square feet or 943 Square metres
   Displacement factor (Displacement / loading): 74 %
   Structure weight / hull surface area: 34 lbs/sq ft or 165 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 0,92
      - Overall: 0,53
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent

850 miles @31 knts
Trial speed:31.5
Misc Weigth:
6 TT +1 reload :20 t
Dd FC 25 t

And this one fits into a type 2 slip/dock:

Enter ship name, Enter country Enter ship type laid down 1920

Displacement:
   1.496 t light; 1.557 t standard; 1.884 t normal; 2.146 t full load

Dimensions: Length overall / water x beam x draught
   387,11 ft / 383,86 ft x 42,65 ft x 10,17 ft (normal load)
   117,99 m / 117,00 m x 13,00 m  x 3,10 m

Armament:
      6 - 4,92" / 125 mm guns (3x2 guns), 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in deck mounts
     on centreline ends, majority forward, 1 raised mount - superfiring
      4 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,88kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 365 lbs / 166 kg
   Shells per gun, main battery: 110
   6 - 19,7" / 500 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 3 shafts, 30.675 shp / 22.884 Kw = 31,00 kts
   Range 850nm at 31,00 kts
   Bunker at max displacement = 589 tons

Complement:
   142 - 185

Cost:
   £0,508 million / $2,032 million

Distribution of weights at normal displacement:
   Armament: 46 tons, 2,4 %
   Machinery: 887 tons, 47,1 %
   Hull, fittings & equipment: 519 tons, 27,5 %
   Fuel, ammunition & stores: 388 tons, 20,6 %
   Miscellaneous weights: 45 tons, 2,4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     702 lbs / 318 Kg = 11,8 x 4,9 " / 125 mm shells or 0,4 torpedoes
   Stability (Unstable if below 1.00): 1,78
   Metacentric height 3,6 ft / 1,1 m
   Roll period: 9,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 48 %
         - Recoil effect (Restricted arc if above 1.00): 0,10
   Seaboat quality  (Average = 1.00): 0,91

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,396
   Length to Beam Ratio: 9,00 : 1
   'Natural speed' for length: 19,59 kts
   Power going to wave formation at top speed: 61 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18,44 ft / 5,62 m
      - Forecastle (20 %):   13,85 ft / 4,22 m
      - Mid (50 %):      13,85 ft / 4,22 m
      - Quarterdeck (15 %):   13,85 ft / 4,22 m
      - Stern:      13,85 ft / 4,22 m
      - Average freeboard:   14,21 ft / 4,33 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 172,7 %
      - Above water (accommodation/working, high = better): 145,3 %
   Waterplane Area: 10.056 Square feet or 934 Square metres
   Displacement factor (Displacement / loading): 74 %
   Structure weight / hull surface area: 34 lbs/sq ft or 166 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 0,94
      - Overall: 0,53
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

850 miles @31 knots
Trial speed:31.5
Misc Weight:
6 TT +1 reload :20 t
Dd FC 25 t

sea-keeping after suggestions:1.82

[Guinness]

Getting warmer, but I still think it's BC is way too low for a ship of it's size and it's freeboard is too high.

Also, our rules require hoists for twin mounts on DDs.

Being able to cruise at 31 knots for nearly 27.5 hours may be excessive.

[Tanthalas]

Being able to cruise at 31 knots for nearly 27.5 hours may be excessive.

That depends on what its intended to cruise with... im seting cruise at 19 knots for 2900 NM on my DDs but I intend them to cruise withthe  Asfaloth class BBs and the Eldacar class CCs so they have to have some serious range. I however do think the range is a tad on the extream side for these.

That said I still dont think they are fast enough since my 1K ton jobs are making 32 knots without any booster from Trial speed, and my 1500 ton jobs are making 33...

[ledeper]

More tweaking: :D :D
Enter ship name, Enter country Enter ship type laid down 1920

Displacement:
   1.475 t light; 1.534 t standard; 1.800 t normal; 2.013 t full load

Dimensions: Length overall / water x beam x draught
   386,53 ft / 383,86 ft x 42,65 ft x 9,84 ft (normal load)
   117,81 m / 117,00 m x 13,00 m  x 3,00 m

Armament:
      6 - 4,92" / 125 mm guns (3x2 guns), 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in deck mounts with hoists
     on centreline ends, majority forward, 1 raised mount - superfiring
      4 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,88kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 365 lbs / 166 kg
   Shells per gun, main battery: 110
   6 - 19,7" / 500 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 3 shafts, 31.778 shp / 23.707 Kw = 31,50 kts
   Range 675nm at 31,50 kts
   Bunker at max displacement = 479 tons

Complement:
   137 - 179

Cost:
   £0,501 million / $2,004 million

Distribution of weights at normal displacement:
   Armament: 46 tons, 2,5 %
   Machinery: 871 tons, 48,4 %
   Hull, fittings & equipment: 513 tons, 28,5 %
   Fuel, ammunition & stores: 325 tons, 18,1 %
   Miscellaneous weights: 45 tons, 2,5 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     549 lbs / 249 Kg = 9,2 x 4,9 " / 125 mm shells or 0,4 torpedoes
   Stability (Unstable if below 1.00): 1,76
   Metacentric height 3,5 ft / 1,1 m
   Roll period: 9,6 seconds
   Steadiness   - As gun platform (Average = 50 %): 36 %
         - Recoil effect (Restricted arc if above 1.00): 0,16
   Seaboat quality  (Average = 1.00): 0,51

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,391
   Length to Beam Ratio: 9,00 : 1
   'Natural speed' for length: 19,59 kts
   Power going to wave formation at top speed: 62 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      15,16 ft / 4,62 m
      - Forecastle (10 %):   11,48 ft / 3,50 m
      - Mid (50 %):      11,48 ft / 3,50 m
      - Quarterdeck (15 %):   11,48 ft / 3,50 m
      - Stern:      11,48 ft / 3,50 m
      - Average freeboard:   11,63 ft / 3,54 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 177,9 %
      - Above water (accommodation/working, high = better): 124,6 %
   Waterplane Area: 10.030 Square feet or 932 Square metres
   Displacement factor (Displacement / loading): 68 %
   Structure weight / hull surface area: 36 lbs/sq ft or 177 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 0,69
      - Overall: 0,51
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent
   Caution: Lacks seaworthiness - very limited seakeeping ability

850 miles @31 knts
Trial speed:31.5
Misc Weigth:
6 TT +1 reload :20 t
Dd FC 25 t

[Tanthalas]

Machinery: 871 tons, 48,4 %

Try and push that to 50%+ this is from my 1500 ton can

Machinery: 1,002 tons, 54.0 %

as you can see a tad bit higher LOL

[Sachmle]

While I'm well aware it's within the rule set, I really don't like seeing twin mounts on DDs. I know this isn't OTL, but it's all I can really go off, and in OTL I don't remember twin mounts on any DDs pre-1930s (I'm probably wrong and someone(s) will point that out shortly w/ massive links and examples so :P) and most of them IIRC were 2k+ jobs like Porter's and the French superDDs. Just my $0.02.

[Sachmle]

Beat y'all to the examples:

Appears Italy liked twin mounts starting w/ the Leone Class in 1921. It was however 2 twin 12cm guns, not 3 twin 12.5cm and it was on ~2,700t full not ~2,000t.

1st US Twin mount DD: Porter Class laid down 1933 4x2x5" (12.7cm) ~2,600t full
1st RN Twin mount DD: Tribal Class laid down 1939 4x2x4.7" (12cm) ~2,500t full
1st KM Twin mount DD: Type 1936c laid down 1943 3x2x5" (12.7cm) ~3,700t full
1st IJN Twin mount DD: Fubuki Class laid down 1929 3x2x5" (12.7cm) ~2,300t full
1st MN Twin mount DD: Mogador Class laid down 1934 4x2x5.4" (13.8cm) ~ 4,000t full load.

[Guinness]

Written before Sam's last post:

The Italians and Japanese tinkered with them between the wars, but I don't remember exactly what years. 3 (or so) of the US flush deckers had twin 4" mounts too. I think a twin 105mm or so mount with no hoists ought to be ok. It's mainly a deckspace saving arrangement. On a ship with sufficient beam, working a twin mount of that size shouldn't be a big deal.

Of course, here I'm not talking about Nverse style unarmored light cruisers built to DD rules.

As far as range: It makes more sense if there's an operational requirement, but on this ship fuel is a full 1/4 of full load displacement. That seems like a lot. US DDs shipped nearly that much fuel in WW2, but I think it can be argued they were a special case given the scope of that war. And in the Nverse, we have lots more land in the middle of the Pacific than OTL. :)

At any rate, this discussion is healthy, I think.

[Carthaginian]

The Fabuki class was designed and approved in 1923 and ships were constructed between 1926 and 1931 based on their initial design. They were the first ships to bring the enclosed mount and hoists to a destroyer class, the first destroyers able to bump up against 40 knots (38-39 knots average) and were among the largest and longest ranged before WWII.

The destroyers in N-verse were getting out of hand for the period long before I left. Too much hindsight got wrapped into everyone's designs (including my own) and we wound up with WWI designs in the early 1900's and now are approaching WWII designs in 1918.

Honestly, a sense of morbid curiosity makes me want to sit back and see what happens. If the Fabuki class is built in 1918 N-verse... what will destroyers of 1930 look like? ;)

[Walter]

Like this of course. ;D