French sloops

[maddox]

A project that has to fill in the gap between the 500 tons DD's of the Plumeau class and the Demarce class cruisers that are being churned out by the French yards.

France lacks appropriate DD tech, and therefore has 2 options. Or buy foreign, or ignore the DD tech.

The ignoring the DD tech has 1 advantage, and 1 disadvantage. Ships with the same capacities as a foreign destroyer will be twice as large.
A design, albeit slow with 27 kts has some appeal. The huge range- for a DD- of 6000nm and the good seakeeping qualities have their advantages.  With 130 misc weight, the options are available to fit new technologies.

Gauloise, French  Destroyer equivalent laid down 1912

Displacement:
   2.501 t light; 2.612 t standard; 3.108 t normal; 3.506 t full load

Dimensions: Length overall / water x beam x draught
   393,70 ft / 393,70 ft x 39,37 ft x 12,47 ft (normal load)
   120,00 m / 120,00 m x 12,00 m  x 3,80 m

Armament:
      6 - 5,51" / 140 mm guns in single mounts, 92,59lbs / 42,00kg shells, 1912 Model
     Quick firing guns in deck mounts with hoists
     on centreline, evenly spread, 3 raised mounts
      12 - 2,76" / 70,0 mm guns in single mounts, 10,47lbs / 4,75kg shells, 1912 Model
     Quick firing guns in deck mounts
     on side, all amidships, 6 raised mounts - superfiring
   Weight of broadside 681 lbs / 309 kg
   Shells per gun, main battery: 120
   6 - 20,0" / 508 mm above water torpedoes

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1,00" / 25 mm   1,00" / 25 mm      1,00" / 25 mm
   2nd:   0,50" / 13 mm   0,50" / 13 mm            -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 25.215 shp / 18.810 Kw = 27,00 kts
   Range 6.000nm at 14,00 kts
   Bunker at max displacement = 894 tons

Complement:
   207 - 270

Cost:
   £0,294 million / $1,177 million

Distribution of weights at normal displacement:
   Armament: 78 tons, 2,5%
   Armour: 40 tons, 1,3%
      - Belts: 0 tons, 0,0%
      - Torpedo bulkhead: 0 tons, 0,0%
      - Armament: 40 tons, 1,3%
      - Armour Deck: 0 tons, 0,0%
      - Conning Tower: 0 tons, 0,0%
   Machinery: 1.005 tons, 32,3%
   Hull, fittings & equipment: 1.247 tons, 40,1%
   Fuel, ammunition & stores: 607 tons, 19,5%
   Miscellaneous weights: 130 tons, 4,2%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     2.484 lbs / 1.127 Kg = 29,7 x 5,5 " / 140 mm shells or 0,6 torpedoes
   Stability (Unstable if below 1.00): 1,17
   Metacentric height 1,7 ft / 0,5 m
   Roll period: 12,8 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0,70
   Seaboat quality  (Average = 1.00): 1,20

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,563
   Length to Beam Ratio: 10,00 : 1
   'Natural speed' for length: 19,84 kts
   Power going to wave formation at top speed: 59 %
   Trim (Max stability = 0, Max steadiness = 100): 59
   Bow angle (Positive = bow angles forward): -5,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      22,97 ft / 7,00 m
      - Forecastle (20%):   16,40 ft / 5,00 m
      - Mid (50%):      13,88 ft / 4,23 m
      - Quarterdeck (15%):   13,62 ft / 4,15 m
      - Stern:      13,45 ft / 4,10 m
      - Average freeboard:   15,19 ft / 4,63 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 128,7%
      - Above water (accommodation/working, high = better): 109,9%
   Waterplane Area: 10.950 Square feet or 1.017 Square metres
   Displacement factor (Displacement / loading): 111%
   Structure weight / hull surface area: 67 lbs/sq ft or 326 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,93
      - Longitudinal: 1,80
      - Overall: 1,00
   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
   Good seaboat, rides out heavy weather easily

[Borys]

Too big and too slow for torpedo attacks.
But scary nonetheless.
You can churn out half a dozen of these a year.
After a couple of years you'll be able to block large swathes of the Ocean of any shipping you dislike.
Borys

[miketr]

It's about the same as my San Juan class.  I got 28 knots on the same displacement, of course I had way less firepower than yours does.

http://www.navalism.org/index.php?topic=674.msg24435#msg24435

The improved San Juan's odds are never to be built.

http://www.navalism.org/index.php?topic=2100.msg27084#msg27084
Another half knot of speed, twin gun mounts and a bit more range.

If you really want to use these as TBD fill in then I would suggest at least 29 knots for whatever design you use.

Michael

[Borys]

The French ship has the QUANTITY which you will never match - your ships must be better on an individual basis.
Your 8 San Juans cannot compare with the dozens of Gauloise which France can churn out at the rate of 6-8 a year.
Borys

[miketr]

The French ship has the QUANTITY which you will never match - your ships must be better on an individual basis.
Your 8 San Juans cannot compare with the dozens of Gauloise which France can churn out at the rate of 6-8 a year.
Borys

To keep the thread jacking to a min... I will leave it at that I can't afford 6 to 8 San Jaun's a year.  I am just suggesting another design in about the same size class and roughly the same mission.

Michael

[Borys]

OK, OK!
Yes, another ship, which IIRC I criticised, is broadely similar :)

Borys

[miketr]

One thing I do wonder is there the deck foot print for all those guns on the French sloop.  I had trouble fitting the weapons I did.  This has another main gun and eight more secondaries.

[Borys]

One thing I do wonder is there the deck foot print for all those guns on the French sloop.  I had trouble fitting the weapons I did.  This has another main gun and eight more secondaries.

Good point. IMO there is no space for those 2,75" guns.
With poor firing arcs, the 6x14cm guns could be crammed into such a ship, I suppose:
http://www.german-navy.de/pics/hochseeflotte/gtb1916.gif

As the French design is 40' longer, a fifth gun could be fitted be rather easily fitted.
Borys

[Korpen]

One thing I do wonder is there the deck foot print for all those guns on the French sloop.  I had trouble fitting the weapons I did.  This has another main gun and eight more secondaries.

Good point. IMO there is no space for those 2,75" guns.
With poor firing arcs, the 6x14cm guns could be crammed into such a ship, I suppose:
http://www.german-navy.de/pics/hochseeflotte/gtb1916.gif

As the French design is 40' longer, a fifth gun could be fitted be rather easily fitted.
Borys

We got Groningen with seven centerline guns: http://www.navalism.org/index.php?topic=679.msg11101#msg11101
Yes, she is much larger, but the amount of deckspace is similar.
So I do not think there is any major problems with fitting the main guns, but the 7cm guns will most likley cut down the firing arcs of the fourteens quite a bit.
But without a drawing it is very hard to tell. ;)

[maddox]

A non French DD design that almost fullfills all the wishes by the MN.

Pity about the cramped crew quarters, again, that will be seen as a degradation of the High standard the French crews anticipate with new ships.

Belga, French Destroyer laid down 1912

Displacement:
   1.003 t light; 1.047 t standard; 1.179 t normal; 1.285 t full load

Dimensions: Length overall / water x beam x draught
   311,68 ft / 305,12 ft x 26,25 ft x 11,15 ft (normal load)
   95,00 m / 93,00 m x 8,00 m  x 3,40 m

Armament:
      2 - 5,51" / 140 mm guns in single mounts, 92,59lbs / 42,00kg shells, 1912 Model
     Quick firing guns in deck mounts
     on centreline ends, evenly spread
      6 - 2,76" / 70,0 mm guns in single mounts, 10,47lbs / 4,75kg shells, 1912 Model
     Quick firing guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 248 lbs / 112 kg
   Shells per gun, main battery: 140
   6 - 20,0" / 508 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 19.408 shp / 14.479 Kw = 29,00 kts
   Range 4.000nm at 12,00 kts
   Bunker at max displacement = 237 tons

Complement:
   99 - 130

Cost:
   £0,136 million / $0,546 million

Distribution of weights at normal displacement:
   Armament: 29 tons, 2,4%
   Machinery: 551 tons, 46,8%
   Hull, fittings & equipment: 363 tons, 30,8%
   Fuel, ammunition & stores: 176 tons, 15,0%
   Miscellaneous weights: 60 tons, 5,1%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     362 lbs / 164 Kg = 4,3 x 5,5 " / 140 mm shells or 0,2 torpedoes
   Stability (Unstable if below 1.00): 1,20
   Metacentric height 0,9 ft / 0,3 m
   Roll period: 11,4 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0,50
   Seaboat quality  (Average = 1.00): 1,24

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,462
   Length to Beam Ratio: 11,63 : 1
   'Natural speed' for length: 17,47 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 57
   Bow angle (Positive = bow angles forward): -5,00 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%):   14,76 ft / 4,50 m
      - Mid (50%):      11,48 ft / 3,50 m
      - Quarterdeck (15%):   9,84 ft / 3,00 m
      - Stern:      9,84 ft / 3,00 m
      - Average freeboard:   12,49 ft / 3,81 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 175,3%
      - Above water (accommodation/working, high = better): 62,3%
   Waterplane Area: 5.160 Square feet or 479 Square metres
   Displacement factor (Displacement / loading): 64%
   Structure weight / hull surface area: 32 lbs/sq ft or 155 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,61
      - Longitudinal: 2,34
      - Overall: 0,70
   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
   Good seaboat, rides out heavy weather easily

[Borys]

3 tones overweight :)

And IMO the 14cm guns are wastedweight - on such a small hull they are difficult to operate and load. At higher speeds usuelss.
But if the customer wants them ...

Borys

[maddox]

An Italian design for a Destroyer, designed to fit in the French fleet.

Brosse, French Torpedo boat destroyer laid down 1913 (Engine 1912)

Displacement:
   748 t light; 785 t standard; 926 t normal; 1.039 t full load

Dimensions: Length overall / water x beam x draught
   331,36 ft / 328,08 ft x 29,53 ft x 8,37 ft (normal load)
   101,00 m / 100,00 m x 9,00 m  x 2,55 m

Armament:
      5 - 4,13" / 105 mm guns in single mounts, 35,32lbs / 16,02kg shells, 1913 Model
     Quick firing guns in deck mounts
     on centreline ends, majority forward, 2 raised mounts - superfiring
      2 - 0,98" / 25,0 mm guns in single mounts, 0,48lbs / 0,22kg shells, 1913 Model
     Machine guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 178 lbs / 81 kg
   Shells per gun, main battery: 180
   6 - 20,0" / 508 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 13.510 shp / 10.078 Kw = 28,00 kts
   Range 5.000nm at 12,00 kts
   Bunker at max displacement = 255 tons

Complement:
   83 - 109

Cost:
   £0,110 million / $0,441 million

Distribution of weights at normal displacement:
   Armament: 22 tons, 2,4%
   Machinery: 402 tons, 43,4%
   Hull, fittings & equipment: 254 tons, 27,4%
   Fuel, ammunition & stores: 178 tons, 19,2%
   Miscellaneous weights: 70 tons, 7,6%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     307 lbs / 139 Kg = 8,7 x 4,1 " / 105 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,41
   Metacentric height 1,5 ft / 0,4 m
   Roll period: 10,3 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0,21
   Seaboat quality  (Average = 1.00): 1,21

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,400
   Length to Beam Ratio: 11,11 : 1
   'Natural speed' for length: 18,11 kts
   Power going to wave formation at top speed: 57 %
   Trim (Max stability = 0, Max steadiness = 100): 58
   Bow angle (Positive = bow angles forward): -5,00 degrees
   Stern overhang: 3,28 ft / 1,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      20,34 ft / 6,20 m
      - Forecastle (20%):   11,48 ft / 3,50 m
      - Mid (50%):      9,84 ft / 3,00 m
      - Quarterdeck (15%):   9,84 ft / 3,00 m
      - Stern:      9,84 ft / 3,00 m
      - Average freeboard:   11,13 ft / 3,39 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 167,2%
      - Above water (accommodation/working, high = better): 85,7%
   Waterplane Area: 5.963 Square feet or 554 Square metres
   Displacement factor (Displacement / loading): 70%
   Structure weight / hull surface area: 25 lbs/sq ft or 122 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,51
      - Longitudinal: 0,94
      - Overall: 0,54
   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
   Good seaboat, rides out heavy weather easily

Misc weight
24 tons torpedo and tubes
5 tons very small marconi
11 ton crew comfort messures (Insulation, heating and ventilation/cooling of the messroom)
10 ton mines
20 tons reserve.

[Borys]

gub-boatish ...
and the number of mounts seems to be off

[maddox]

The amount of mounts was off due a typo. Doesn't affect the ship, and is corrected in the file.

But what is "gub-boatish"

I know, she's slow, but slow in all weather and with a good range. Pity 6000Nm range  affected her to much.

And the cramped quarters for the crew won't make her popular.
At least non of the 140mm QF guns are placed on her.

[Borys]

Gub-boatish is a typo. I meant gun-boatish, i.e. too many too big guns and too slow to be a destroyer. I.e. a "gunboat".
Yes, the lack of 14cm QF guns makes them more potent in combat.

Borys