Maori DE-1913 (final version)

[Valles]

DE-1913, Maori Destroyer laid down 1913 (Engine 1909)

Displacement:
   998 t light; 1,037 t standard; 1,263 t normal; 1,443 t full load

Dimensions: Length overall / water x beam x draught
   305.31 ft / 295.28 ft x 29.53 ft x 9.84 ft (normal load)
   93.06 m / 90.00 m x 9.00 m  x 3.00 m

Armament:
      1 - 5.91" / 150 mm guns in single mounts, 110.23lbs / 50.00kg shells, 1913 Model
     Quick firing gun in a deck mount with hoist
     on centreline forward
      2 - 2.95" / 75.0 mm guns in single mounts, 13.23lbs / 6.00kg shells, 1913 Model
     Breech loading guns in deck mounts with hoists
     on centreline, evenly spread
   Weight of broadside 137 lbs / 62 kg
   Shells per gun, main battery: 175
   3 - 17.7" / 450 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 18,793 shp / 14,020 Kw = 28.00 kts
   Range 4,000nm at 14.00 kts
   Bunker at max displacement = 406 tons

Complement:
   105 - 137

Cost:
   £0.150 million / $0.599 million

Distribution of weights at normal displacement:
   Armament: 16 tons, 1.3 %
   Machinery: 635 tons, 50.3 %
   Hull, fittings & equipment: 305 tons, 24.2 %
   Fuel, ammunition & stores: 265 tons, 21.0 %
   Miscellaneous weights: 42 tons, 3.3 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     341 lbs / 155 Kg = 3.3 x 5.9 " / 150 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.34
   Metacentric height 1.4 ft / 0.4 m
   Roll period: 10.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 75 %
         - Recoil effect (Restricted arc if above 1.00): 0.33
   Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.515
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 17.18 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 71
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 6.56 ft / 2.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19.69 ft / 6.00 m
      - Forecastle (20 %):   16.40 ft / 5.00 m
      - Mid (50 %):      16.40 ft / 5.00 m (8.20 ft / 2.50 m aft of break)
      - Quarterdeck (15 %):   8.20 ft / 2.50 m
      - Stern:      8.20 ft / 2.50 m
      - Average freeboard:   12.57 ft / 3.83 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 175.9 %
      - Above water (accommodation/working, high = better): 106.5 %
   Waterplane Area: 5,890 Square feet or 547 Square metres
   Displacement factor (Displacement / loading): 67 %
   Structure weight / hull surface area: 28 lbs/sq ft or 135 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.52
      - Overall: 0.55
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate
   Ship has slow, easy roll, a good, steady gun platform

25 tons torpedo fire control
10 tons short-range wireless
6 tons 450mm torpedoes

The one I'd originally planned to build, I don't have the technology for. So, try this on for size, instead.

[Borys]

Weird.
A fast gunboat/aviso.
3" don't need hoists.
Borys

[Valles]

3" don't need hoists.

They do when they're fully enclosed against the elements.

Also, the torpedo mount is... well, kinda weird. It's the same stacked arrangement I used on my previous designs, with three tubes centerline at deck-level aft, then three more on an open platform above those. From above, all six tubes share the same deckspace as an ordinary triple mount, hence the simming.

They're really just a straight evolution of the existing two Maori destroyer designs.

[Borys]

A double-decker triple mount looks like a sextuple mount to me ...
Borys

[Korpen]

I think it is better to sim six  torpedo tubes as six tubes (and less debate). After all having six tubes piled on top of each other do not give you more deck space then having to triple tubes with a platform for other purposes on top would. Also I think one will have to take the space into consideration, to work, maintain, reload and aim the tubes one need a not insignificant amount of space for people to work in. In short I think it is a lot of unnecessary extra weight (an extra platform of some 10 tons at least) on a ship that have no shortages of deckspace whatsoever.

You should stick 2-3mm thick armour on the mounts if you want them enclosed.

On a more conceptual basis I find her interesting, but I am curious as to the choice of armament; it seem like the single 15cm gun, while hard-hitting lacks the rate of fire to be a good weapon all alone as single guns gives the fire control very little to work with. The 75mm guns, while having excellent rate of fire, might lack punch against all but the smallest potential opponents. So it would be very interesting to learn more about the thinking underpinning the design choices as I fell I am missing something. :) 

[Jefgte]

2-3mm thick armour on the mounts is very thin & fragile in heavy sea

Prefer 0.25" - 6.35mm


Jef

[Korpen]

2-3mm thick armour on the mounts is very thin & fragile in heavy sea

Prefer 0.25" - 6.35mm


Jef

It is thin, but enough going by that sort of steel that went into the superstructure of Swedish destroyers.
6,35mm is excessive for just weather shielding.

[maddox]

On seafaring vessels, hi strenght 8mm steel sheet is common for light upper structure .

2 - 3 mm will buckle with heavy waves if used in unbraced sheet larger than a safetylocker or such.
Also, will corrode away in a year of 3-4 even with intensive maintenance.

Jef is right in that respect, 1/4" is light/normal.

[Valles]

DE-1913, Maori Destroyer laid down 1913 (Engine 1909)

Displacement:
   1,000 t light; 1,039 t standard; 1,265 t normal; 1,446 t full load

Dimensions: Length overall / water x beam x draught
   301.74 ft / 295.28 ft x 29.53 ft x 9.84 ft (normal load)
   91.97 m / 90.00 m x 9.00 m  x 3.00 m

Armament:
      1 - 5.91" / 150 mm guns in single mounts, 110.23lbs / 50.00kg shells, 1913 Model
     Quick firing gun in a deck mount with hoist
     on centreline forward
      2 - 2.95" / 75.0 mm guns in single mounts, 13.23lbs / 6.00kg shells, 1913 Model
     Breech loading guns in deck mounts with hoists
     on centreline, evenly spread
   Weight of broadside 137 lbs / 62 kg
   Shells per gun, main battery: 175
   6 - 17.7" / 450 mm above water torpedoes

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.20" / 5 mm   0.20" / 5 mm            -
   2nd:   0.20" / 5 mm   0.20" / 5 mm            -

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 18,827 shp / 14,045 Kw = 28.00 kts
   Range 4,000nm at 14.00 kts
   Bunker at max displacement = 406 tons

Complement:
   105 - 137

Cost:
   £0.150 million / $0.600 million

Distribution of weights at normal displacement:
   Armament: 16 tons, 1.3 %
   Armour: 2 tons, 0.1 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 2 tons, 0.1 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 636 tons, 50.3 %
   Hull, fittings & equipment: 305 tons, 24.1 %
   Fuel, ammunition & stores: 265 tons, 21.0 %
   Miscellaneous weights: 41 tons, 3.2 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     341 lbs / 155 Kg = 3.3 x 5.9 " / 150 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.34
   Metacentric height 1.3 ft / 0.4 m
   Roll period: 10.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 73 %
         - Recoil effect (Restricted arc if above 1.00): 0.33
   Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.516
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 17.18 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 71
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18.04 ft / 5.50 m
      - Forecastle (20 %):   16.40 ft / 5.00 m
      - Mid (50 %):      16.40 ft / 5.00 m (8.20 ft / 2.50 m aft of break)
      - Quarterdeck (15 %):   8.20 ft / 2.50 m
      - Stern:      8.20 ft / 2.50 m
      - Average freeboard:   12.43 ft / 3.79 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 175.8 %
      - Above water (accommodation/working, high = better): 84.9 %
   Waterplane Area: 5,895 Square feet or 548 Square metres
   Displacement factor (Displacement / loading): 67 %
   Structure weight / hull surface area: 28 lbs/sq ft or 136 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.48
      - Overall: 0.56
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Ship has slow, easy roll, a good, steady gun platform

25 tons torpedo fire control
10 tons short-range wireless
6 tons 450mm torpedoes

Personally I don't care whether the boat is listed with three or six torpedoes, but SS evidently disagrees with Korpen. That was the entire reason for the arrangement in the first place.

[Korpen]

Personally I don't care whether the boat is listed with three or six torpedoes, but SS evidently disagrees with Korpen. That was the entire reason for the arrangement in the first place.

Errr... No springsharp agrees with me, six tubes takes up about equally much space no matter the arrangement. But of course it will take up less space if they are not included in the sim at all...
Secondly, it is space for "accommodation/working", not deckspace we are talking about, it is not the same thing as springsharp have no concept of the later.

[P3D]

What ships this destroyer is supposed to fight? Against smaller ships, the armament is inadequate (ROF too low). One gun won't have much effect on cruisers as spotting for one gun is not really accurate.
Against capital ships, when the slowest new ships in the region are the 23+kts DKB battleships, the speed is not enough. Then you have the rest 27-28kts battlecruisers.

[Valles]

Well, something relatively fast is needed, yes?

A seaboat rating of less that 1.0 is death sentence to a crew operating in Maoria's southern coastal waters.

Serving a gun in the open, likewise.

An enclosed mount without an ammunition hoist is of extremely limited value due to storage space issues.

Ammo hoists have consequences for hull strength; high freeboard, likewise.

I have 150mm guns and 75mm guns, but nothing in between. 75mm is inadequate as a primary gun for a front-line warship. A 1000 ton vessel with acceptable seakeeping cannot carry more than one hoisted 150mm gun.

In short, you say that a destroyer is worthless if it's not 30+ knots and armed to kill with its guns. I say a destroyer is worthless if it sinks in a once-a-month storm.

And, Korpen, since when did SS have a concept of space at all? Particularly the vertical sort?

[Borys]

Why not develop/by a gun in the 3,5"- 4"-4,5" range?
Borys

[Valles]

A 100mm or 125mm gun - likely the former - is on my 'to do' list, but won't be available for this design in any case.

[maddox]

Buy Foreign then.
France has a nice 105mm gun available.