Simming destroyers - alternative

[P3D]

The lower overall strength is mainly there to represent the higher SHP/ton value of the destroyer machinery. SS machinery changes from 13.2 SHP/ton in 1905 to 30 in 1924. Meanwhile DD machinery is basically constant at 60-70.

Another go-around is to use negative misc. weight to compensate for the light machinery. There's an error message about it but that can be ignored, and composite strength is calculated nonetheless. Stability is way off but it is usually not an issue with destroyers, and steadiness is a bit (2-3) better due to negative misc weight.

One design for a 750t destroyer, 31 knots with oil-firing and 3000nm@12kts range. Composite strength is 1.00. 15t misc. weight. With keeping the cross sectional strength at 0.50, max speed of the design is 30-30.2kts, basically one knot slower.

Enter ship name, Enter country Enter ship type laid down 1909

Displacement:
   751 t light; 782 t standard; 878 t normal; 954 t full load

Dimensions: Length overall / water x beam x draught
   280.00 ft / 280.00 ft x 27.00 ft x 9.00 ft (normal load)
   85.34 m / 85.34 m x 8.23 m  x 2.74 m

Armament:
      4 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1909 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread
     2 guns in hull casemates - Limited use in all but light seas
   Weight of broadside 128 lbs / 58 kg
   Shells per gun, main battery: 200
   4 - 20.0" / 508 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 22,759 shp / 16,978 Kw = 31.00 kts
   Range 3,000nm at 12.00 kts
   Bunker at max displacement = 172 tons

Complement:
   79 - 104

Cost:
   £0.115 million / $0.460 million

Distribution of weights at normal displacement:
   Armament: 16 tons, 1.8 %
   Machinery: 537 tons, 61.2 %
   Hull, fittings & equipment: 451 tons, 51.4 %
   Fuel, ammunition & stores: 127 tons, 14.5 %
   Miscellaneous weights: -254 tons, -28.9 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     615 lbs / 279 Kg = 19.2 x 4.0 " / 102 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 2.51
   Metacentric height 2.8 ft / 0.9 m
   Roll period: 6.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 63 %
         - Recoil effect (Restricted arc if above 1.00): 0.10
   Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.452
   Length to Beam Ratio: 10.37 : 1
   'Natural speed' for length: 16.73 kts
   Power going to wave formation at top speed: 69 %
   Trim (Max stability = 0, Max steadiness = 100): 60
   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:      17.74 ft / 5.41 m
      - Forecastle (20 %):   17.00 ft / 5.18 m
      - Mid (45 %):      17.00 ft / 5.18 m (9.00 ft / 2.74 m aft of break)
      - Quarterdeck (15 %):   9.00 ft / 2.74 m
      - Stern:      9.00 ft / 2.74 m
      - Average freeboard:   12.66 ft / 3.86 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 180.8 %
      - Above water (accommodation/working, high = better): 94.1 %
   Waterplane Area: 4,829 Square feet or 449 Square metres
   Displacement factor (Displacement / loading): 45 %
   Structure weight / hull surface area: 45 lbs/sq ft or 219 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.85
      - Longitudinal: 4.04
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate

[maddox]

If it affects hull integrety so much, it seems obvious I could build a  BB sized .5 cross sectional superbattleship.

I myself oppose this new  negative misc weight idea; just because it violates the roots of the Nverse, Springsharp with all the quirks and non historical issues included.

[P3D]

I realized I can manipulate range with keeping normal displacement constant to account for the weight difference.

However, the biggest difference between SS2 and RL is freeboard. The 'L' class destroyer of the RN had an average freeboard below 9', while SS default is 11.9'. Now I need 13.7' just to get average (1.00) seakeeping. That accounts for 0.2-0.25 composite strength itself! Composite strength with the low freeboard is 0.72-0.75.

Basically all N-verse destroyer designs are crap, everyone used artificial requirement (SS 'seakeeping') which are completely irrelevant.
A 1200-1500t destroyer has a 8-9' freeboard after the raised forecastle at normal displacement.
WWII tribals have 11' freeboard, on 1959t normal.

[Borys]

Ahoj!
We all know that SS sucks for vessels smaller than destroyers. Producing such unrealistic contraptions like your exemplary 950 tonnes load 4x4" 31 knots vessel. Such vessels were possible on more or less 1500 load, starting at c. 1200 light.

So what - for anything smaller than 2 or 3 thousand tonnes light we use RL ships?

Borys

[P3D]

Look at this thread for my attempts. If SS could calculate SHP and engine weight correctly, there won't be any big problems. And everyone would have to disregard seakeeping values.
Another glaring error is that all the N-verse destroyers just have too low ranges.

http://warships1discussionboards.yuku.com/topic/4408?page=-1

[P3D]

Historical design - Beagle class. Pretty close, 0.97 strength.  The 30kts Laforey class OTOH is hopeless. I could get that only with 27kts for 1.02 strength.

Displacement:
   809 t light; 834 t standard; 950 t normal; 1,043 t full load

Dimensions: Length overall / water x beam x draught
   269.00 ft / 269.00 ft x 27.00 ft x 9.50 ft (normal load)
   81.99 m / 81.99 m x 8.23 m  x 2.90 m

Armament:
      1 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1909 Model
     Breech loading gun in deck mount
     on centreline forward
      3 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1909 Model
     Breech loading guns in deck mounts
     on side, all amidships
   Weight of broadside 73 lbs / 33 kg
   Shells per gun, main battery: 120
   2 - 21.0" / 533.4 mm above water torpedoes

Machinery:
   Coal fired boilers, steam turbines,
   Direct drive, 3 shafts, 14,109 shp / 10,526 Kw = 27.10 kts
   Range 2,500nm at 12.00 kts
   Bunker at max displacement = 209 tons (100% coal)

Complement:
   85 - 111

Cost:
   £0.104 million / $0.417 million

Distribution of weights at normal displacement:
   Armament: 9 tons, 1.0 %
   Machinery: 489 tons, 51.4 %
   Hull, fittings & equipment: 300 tons, 31.5 %
   Fuel, ammunition & stores: 141 tons, 14.8 %
   Miscellaneous weights: 12 tons, 1.3 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     379 lbs / 172 Kg = 11.8 x 4.0 " / 102 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.61
   Metacentric height 1.6 ft / 0.5 m
   Roll period: 9.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 31 %
         - Recoil effect (Restricted arc if above 1.00): 0.05
   Seaboat quality  (Average = 1.00): 0.39

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.482
   Length to Beam Ratio: 9.96 : 1
   'Natural speed' for length: 16.40 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   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:      15.00 ft / 4.57 m
      - Forecastle (20 %):   15.00 ft / 4.57 m (7.00 ft / 2.13 m aft of break)
      - Mid (50 %):      7.00 ft / 2.13 m
      - Quarterdeck (15 %):   7.00 ft / 2.13 m
      - Stern:      7.00 ft / 2.13 m
      - Average freeboard:   8.60 ft / 2.62 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 174.7 %
      - Above water (accommodation/working, high = better): 60.5 %
   Waterplane Area: 4,761 Square feet or 442 Square metres
   Displacement factor (Displacement / loading): 64 %
   Structure weight / hull surface area: 39 lbs/sq ft or 190 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.93
      - Longitudinal: 1.21
      - Overall: 0.96
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Caution: Lacks seaworthiness - very limited seakeeping ability

[Borys]

Ahoj!
Maybe some helpful data here.
http://www.worldwar1atsea.net/#navies
Borys

[P3D]

I am working from March: RN Destroyers 1892-1953.  500pages , Letter size (roughly A4) so I could hardly find better sources.

I could get more or less historical ships with the following guidelines:
Min. composite strength 0.8
For VTE engines, 0.7 (and engine year 1900 or 1905)
Hull Depth ~16-20', draft 8-11' (for 500-2000t displacements)
Gun mounts must be 'deck mount and hoist'
Misc. Weight for the torpedoes (perhaps increasing it)

I'd say the W/T does not worth 10t misc weight, 5t at most, but it would not really matter.

[Borys]

Ahoj!
So you are well supplied.
Lucky you!
:)

'deck mount and hoist' - our previous research showed that this was not the case, or at least not for all guns, but only one in two or three.

I'm all for the increase in weight cost of torpedos.

Borys

[P3D]

The hoists are needed otherwise the gun mounts have negligible weight. So you are getting 4x5" on a 750t hull.

Another historical design, GTB1918, although I did not have any good displacement data. Speed should be 34kts with the given SHP.

Torpedo weights could be increased by 0.5t each.

Enter ship name, Enter country Enter ship type laid down 1918

Displacement:
   1,398 t light; 1,439 t standard; 1,680 t normal; 1,873 t full load

Dimensions: Length overall / water x beam x draught
   298.56 ft / 298.56 ft x 29.86 ft x 11.81 ft (normal load)
   91.00 m / 91.00 m x 9.10 m  x 3.60 m

Armament:
      4 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1918 Model
     Breech loading guns in deck mounts with hoists
     on centreline, evenly spread, 3 raised mounts
     Aft Main mounts separated by engine room
   Weight of broadside 141 lbs / 64 kg
   Shells per gun, main battery: 100

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 35,629 shp / 26,579 Kw = 31.00 kts
   Range 2,000nm at 20.00 kts
   Bunker at max displacement = 433 tons

Complement:
   130 - 170

Cost:
   £0.388 million / $1.552 million

Distribution of weights at normal displacement:
   Armament: 18 tons, 1.1 %
   Machinery: 931 tons, 55.4 %
   Hull, fittings & equipment: 429 tons, 25.6 %
   Fuel, ammunition & stores: 282 tons, 16.8 %
   Miscellaneous weights: 20 tons, 1.2 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     472 lbs / 214 Kg = 13.4 x 4.1 " / 105 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.71
   Metacentric height 2.0 ft / 0.6 m
   Roll period: 8.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 20 %
         - Recoil effect (Restricted arc if above 1.00): 0.14
   Seaboat quality  (Average = 1.00): 0.16

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.559
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 17.28 kts
   Power going to wave formation at top speed: 72 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   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:      14.76 ft / 4.50 m
      - Forecastle (20 %):   14.76 ft / 4.50 m
      - Mid (35 %):      14.76 ft / 4.50 m (6.56 ft / 2.00 m aft of break)
      - Quarterdeck (15 %):   6.56 ft / 2.00 m
      - Stern:      6.56 ft / 2.00 m
      - Average freeboard:   9.43 ft / 2.88 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 187.8 %
      - Above water (accommodation/working, high = better): 77.7 %
   Waterplane Area: 6,271 Square feet or 583 Square metres
   Displacement factor (Displacement / loading): 61 %
   Structure weight / hull surface area: 42 lbs/sq ft or 205 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.77
      - Longitudinal: 1.05
      - Overall: 0.80
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Ship has quick, lively roll, not a steady gun platform
   Caution: Lacks seaworthiness - very limited seakeeping ability

[Borys]

Ahoj!

And to think it was originally to be armed with 4x15cm :)

Borys

[Borys]

I could get more or less historical ships with the following guidelines:
Min. composite strength 0.8
For VTE engines, 0.7 (and engine year 1900 or 1905)
Hull Depth ~16-20', draft 8-11' (for 500-2000t displacements)
Gun mounts must be 'deck mount and hoist'
Misc. Weight for the torpedoes (perhaps increasing it)

I'd say the W/T does not worth 10t misc weight, 5t at most, but it would not really matter.

So maybe "destroyers" in N-verse have to be 0,8 hull strenght, if larger than 750 or 1000? This will lessen the upheal, as there are not that many vessles in the 750-1000 category, and few, if any, above 1000 tonnes.

Nothing stops us from mounting "small w/t" of 5 tonnes, instead of "medium" 10 tonnes.

If the "with hoist" makes the design better, than OK.

Torpedo weight
18" or less - 2 tonnes a tube
18"- 22" - 3 tonnes a tube
+24" - 4 tonnes a tube
No difference between fixed or not.

There are some 14" torpedos out there - but they should quickly become extinct with progress :)
Can be asumed to be 1 tonne a tube.

I dunno on the beam and depth - I based myself on OTL designs ...

Borys

[Carthaginian]

I base my ships loosely on RL designs.

I am opposed to the 'negative misc. weight. rule, and support keeping the destroyer rules as-is.
It's not really broke, so why fix it?

[P3D]

I base my ships loosely on RL designs.

I am opposed to the 'negative misc. weight. rule, and support keeping the destroyer rules as-is.
It's not really broke, so why fix it?

Because it IS broke. No one is building destroyers with historical freeboard.
And my latest proposal is not the negative weight one.

[P3D]

/quote]
So maybe "destroyers" in N-verse have to be 0,8 hull strenght, if larger than 750 or 1000? This will lessen the upheal, as there are not that many vessles in the 750-1000 category, and few, if any, above 1000 tonnes.

Nothing stops us from mounting "small w/t" of 5 tonnes, instead of "medium" 10 tonnes.

If the "with hoist" makes the design better, than OK.

Torpedo weight
18" or less - 2 tonnes a tube
18"- 22" - 3 tonnes a tube
+24" - 4 tonnes a tube
No difference between fixed or not.
Borys

Borys, most torpedoes would weight 1.5 or 2t (instead of 1 and 1.5t), at least those used.

And if you want 'historical' designs, you unfortunately have to get plans for them to get correct freeboard height+draught (the 'depth').

Now here's my 750t Orange DD with 1905 techs.

Orange DD revisited, laid down 1905

Displacement:
   750 t light; 773 t standard; 844 t normal; 901 t full load

Dimensions: Length overall / water x beam x draught
   275.00 ft / 268.00 ft x 24.00 ft x 9.50 ft (normal load)
   83.82 m / 81.69 m x 7.32 m  x 2.90 m

Armament:
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1905 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread
      4 - 0.40" / 10.2 mm guns in single mounts, 0.03lbs / 0.01kg shells, 1905 Model
     Breech loading guns in deck mounts
     on side, all amidships
   Weight of broadside 64 lbs / 29 kg
   Shells per gun, main battery: 150
   4 - 18.0" / 457.2 mm above water torpedoes

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 12,675 shp / 9,456 Kw = 27.00 kts
   Range 2,000nm at 10.00 kts
   Bunker at max displacement = 128 tons (90% coal)

Complement:
   77 - 101

Cost:
   £0.100 million / $0.399 million

Distribution of weights at normal displacement:
   Armament: 8 tons, 0.9 %
   Machinery: 478 tons, 56.6 %
   Hull, fittings & equipment: 254 tons, 30.1 %
   Fuel, ammunition & stores: 94 tons, 11.1 %
   Miscellaneous weights: 11 tons, 1.3 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     241 lbs / 109 Kg = 7.5 x 4.0 " / 102 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.43
   Metacentric height 1.1 ft / 0.3 m
   Roll period: 9.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 42 %
         - Recoil effect (Restricted arc if above 1.00): 0.17
   Seaboat quality  (Average = 1.00): 0.69

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.483
   Length to Beam Ratio: 11.17 : 1
   'Natural speed' for length: 16.37 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 7.00 ft / 2.13 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      15.00 ft / 4.57 m
      - Forecastle (20 %):   15.00 ft / 4.57 m
      - Mid (30 %):      15.00 ft / 4.57 m (7.00 ft / 2.13 m aft of break)
      - Quarterdeck (15 %):   7.00 ft / 2.13 m
      - Stern:      7.00 ft / 2.13 m
      - Average freeboard:   9.40 ft / 2.87 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 191.3 %
      - Above water (accommodation/working, high = better): 58.9 %
   Waterplane Area: 4,222 Square feet or 392 Square metres
   Displacement factor (Displacement / loading): 39 %
   Structure weight / hull surface area: 32 lbs/sq ft or 158 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.75
      - Longitudinal: 1.45
      - Overall: 0.80
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Caution: Lacks seaworthiness - very limited seakeeping ability