Next generation destroyers 1920-

[ledeper]

Dd 40-50, Esc Dd laid down 1920

Displacement:
   1.500 t light; 1.559 t standard; 2.019 t normal; 2.387 t full load

Dimensions: Length overall / water x beam x draught
   393,31 ft / 390,42 ft x 42,65 ft x 10,66 ft (normal load)
   119,88 m / 119,00 m x 13,00 m  x 3,25 m

Armament:
      2 - 4,92" / 125 mm guns (1x2 guns), 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in deck mount
     on centreline forward
      2 - 4,92" / 125 mm guns in single mounts, 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in deck mounts
     on centreline ends, evenly spread, all raised mounts
      4 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,89kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 246 lbs / 112 kg
   Shells per gun, main battery: 120
   2 - 19,7" / 500 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 27.681 shp / 20.650 Kw = 30,00 kts
   Range 10.000nm at 14,00 kts
   Bunker at max displacement = 828 tons

Complement:
   149 - 195

Cost:
   £0,485 million / $1,940 million

Distribution of weights at normal displacement:
   Armament: 31 tons, 1,5 %
   Machinery: 906 tons, 44,9 %
   Hull, fittings & equipment: 489 tons, 24,2 %
   Fuel, ammunition & stores: 519 tons, 25,7 %
   Miscellaneous weights: 75 tons, 3,7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     733 lbs / 332 Kg = 12,3 x 4,9 " / 125 mm shells or 0,4 torpedoes
   Stability (Unstable if below 1.00): 1,55
   Metacentric height 2,9 ft / 0,9 m
   Roll period: 10,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 76 %
         - Recoil effect (Restricted arc if above 1.00): 0,09
   Seaboat quality  (Average = 1.00): 1,02

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,398
   Length to Beam Ratio: 9,15 : 1
   'Natural speed' for length: 19,76 kts
   Power going to wave formation at top speed: 59 %
   Trim (Max stability = 0, Max steadiness = 100): 75
   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:      16,40 ft / 5,00 m
      - Forecastle (20 %):   13,12 ft / 4,00 m
      - Mid (50 %):      13,12 ft / 4,00 m
      - Quarterdeck (15 %):   13,12 ft / 4,00 m
      - Stern:      13,12 ft / 4,00 m
      - Average freeboard:   13,39 ft / 4,08 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 160,6 %
      - Above water (accommodation/working, high = better): 159,3 %
   Waterplane Area: 10.239 Square feet or 951 Square metres
   Displacement factor (Displacement / loading): 89 %
   Structure weight / hull surface area: 32 lbs/sq ft or 155 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 0,76
      - Overall: 0,52
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform

Trail speed 30.5 knts
Range at max speed:1200 Nm
Torpedoes16 tns (1 reload)
L/RW/L 25tns
Reserve 34 tns(for depthcharges/throwers)

[Guinness]

Obligatory Guinness DD harping: too slow, too much freeboard, way too many guns, BC way too low.

Twin mounts need mount and hoist.

From a rules point of view you should take note of the comment re: twin mounts. 4 guns is at least more reasonable IMHO.

[Jefgte]

IMO,

-Too great range -bunker 828t for 2400t  :o
-Speed too short for 1920 - you could have 32kts
-Good guns armament but not enough torp.


Jef

[ledeper]

Seaboat quality  (Average = 1.00): 1,02

This is the reason for the slow spedd as I am not sure whether we came to any conclusion regarding Seaboat quality.
And as for bunkerage;they shall have more or less the same range as my BBs,thus the range of 10000 nm to tag along the Ocean II class

[ledeper]

some tweaking

Dd 40-50, Esc Dd laid down 1920

Displacement:
   1.500 t light; 1.556 t standard; 2.004 t normal; 2.363 t full load

Dimensions: Length overall / water x beam x draught
   386,87 ft / 383,86 ft x 41,01 ft x 11,15 ft (normal load)
   117,92 m / 117,00 m x 12,50 m  x 3,40 m

Armament:
      2 - 4,92" / 125 mm guns (1x2 guns), 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in a deck mount with hoist
     on centreline forward
      2 - 4,92" / 125 mm guns in single mounts, 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in deck mounts
     on centreline ends, evenly spread, all raised mounts
      4 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,89kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 246 lbs / 112 kg
   Shells per gun, main battery: 100
   4 - 19,7" / 500 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 27.672 shp / 20.643 Kw = 30,00 kts
   Range 9.800nm at 14,00 kts
   Bunker at max displacement = 807 tons

Complement:
   149 - 194

Cost:
   £0,484 million / $1,935 million

Distribution of weights at normal displacement:
   Armament: 31 tons, 1,5 %
   Machinery: 902 tons, 45,0 %
   Hull, fittings & equipment: 497 tons, 24,8 %
   Fuel, ammunition & stores: 504 tons, 25,1 %
   Miscellaneous weights: 70 tons, 3,5 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     706 lbs / 320 Kg = 11,8 x 4,9 " / 125 mm shells or 0,4 torpedoes
   Stability (Unstable if below 1.00): 1,53
   Metacentric height 2,7 ft / 0,8 m
   Roll period: 10,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 72 %
         - Recoil effect (Restricted arc if above 1.00): 0,15
   Seaboat quality  (Average = 1.00): 1,03

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,399
   Length to Beam Ratio: 9,36 : 1
   'Natural speed' for length: 19,59 kts
   Power going to wave formation at top speed: 60 %
   Trim (Max stability = 0, Max steadiness = 100): 70
   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:      17,06 ft / 5,20 m
      - Forecastle (20 %):   13,12 ft / 4,00 m
      - Mid (50 %):      13,12 ft / 4,00 m
      - Quarterdeck (15 %):   13,12 ft / 4,00 m
      - Stern:      13,12 ft / 4,00 m
      - Average freeboard:   13,44 ft / 4,10 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 160,8 %
      - Above water (accommodation/working, high = better): 137,5 %
   Waterplane Area: 9.687 Square feet or 900 Square metres
   Displacement factor (Displacement / loading): 89 %
   Structure weight / hull surface area: 33 lbs/sq ft or 162 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 0,84
      - Overall: 0,52
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform

Trail speed 30.5 knts
Range at max speed:1200 Nm
Torpedoes24 tns (1 reload)
L/RW/L 25tns
Reserve 24 tns(for depthcharges/throwers)

[Nobody]

2 - 4,92" / 125 mm guns (1x2 guns), 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in a deck mount with hoist
     on centreline forward
      2 - 4,92" / 125 mm guns in single mounts, 59,59lbs / 27,03kg shells, 1920 Model
     Quick firing guns in deck mounts
     on centreline ends, evenly spread, all raised mounts

Three guns forward, and only one aft?

[ledeper]

Yep an attempt to "downsize"my destroyers in accordance to our "destroyer overbuilding" discussion. :D

[miketr]

The Italians built a DD in the 20's with four guns in two twin mounts.

[ledeper]

But did we made some sort of agreement concerning Seaboat quality ?
One suggestion was to make Seaboat quality x2 or did it just die away?

[Sachmle]

I believe the general idea was that for DDs a seaboat of 0.50 or better is basically the equivalent to a 1.00 for regular ships (BB,BC, CA, etc.)

IMHO the BC, while within rules, is a little low at 0.399.

[The Rock Doctor]

0.50 and up was considered adequate for destroyers.

[mentat]

  Nice balanced Fleet DD - agree with good range

    - my only query is on only 100 rounds per gun - seems on the light side - with a RoF of 8-10 per minute ? - soon run out  :'(

[Jefgte]

Actually the characs for the next 1500t Tribal class are
2M2x120 - 12TTx533 (4TT3x533) - 32kts - Ld in 1920


Jef  ;)