WesWorld

I was more worried about the number of guns on the centreline and their likely arcs than the gun power. But I guess it could work out (1 forward of the bridge, one admidships, two aft with the 55mm between them).

Quoted from "Hood"

I was more worried about the number of guns on the centreline and their likely arcs than the gun power. But I guess it could work out (1 forward of the bridge, one admidships, two aft with the 55mm between them).

Uh - there are only three main guns... ?(

Edit: My presumption in casting the design was that the torpedo tubes were twins, not singles. In double-checking historical designs, this may not be defensible.

Historically, the first twin mounts on destroyers that I can find are the French Bouclier class laid down in 1909. The American Paulding class of 1910 had twin tubes, the Japanese Sakura class of 1911 had them and the British "L" class of 1912 carried twin tubes. The German navy persisted with single torpedo tubes for destroyers until the V25 class of 1913.

I do not know why this was technically so. In the WW hive-mind does anyone know technical reasons that would have delayed introduction of multi-tube torpedo mounts?

Quoted from "BruceDuncan"

Uh - there are only three main guns...

Doh! That's what comes of reading SS reports before 9am and before my morning coffee!


On the torpedo mount issue, DK Brown's 'The Grand Fleet: Warship Design and Development, 1906-1922' hold no clues, but I'll have a look at my copy of David Lyon's 'Early British Destroyers' which covers this early period in more detail and might hold some answers. At the moment I can only assume it was a weight issue, perhaps affecting the reliable operation of the training gear? (though that seems unlikely) or perhaps clearance issues with the inner torpedo nearest the hull when firing at angles ahead?

Clarification of the twin-mount, or multiple-mount issue, would be quite beneficial. I know that on some historical designs both were carried though mounted in different parts of the hull. The smaller (and lighter) the vessel I could see weight distribution as an issue. Of the historical examples I cited, the twin mounts appeared on vessels that were of 600 tons normal displacement or better.

I'll check Friedman's BRITISH DESTROYERS when I get home...

David Lyon's 'Early British Destroyers' provides perhaps some information.

The first destroyers, the six Havock class 26-knotters had a twin 18in mount albeit one with opposite facing tubes. These had been removed by September 1904 and HMS Shark, Skate, Hardy and Haughty had the tubes and racers and pivots removed as a result of inclining experiments showing how much topweight had accumulated. The other two ships kept there racers and pivots so the tubes could be replaced in wartime. (Note: Conway's 1866-1905 incorrect states all these ships had 2 single 18in tubes). There is nothing on why only singles were used for all subsequent torpedo boats. Would the topweight of 2x1 18in be less than 1x2 given the duplicated mounts etc.?

Conway's shows the Sharpshooter Class torpedo gunboats and the following Alarm Class had twin 14in mounts, the Halycon's had twin 18in mounts. All of these were 730-1,000 tons.

I am willing to accept that on a 300-400 ton hull, two sets of twin torpedoes might have been too much topweight; on an 800 ton hull, I would not think it that much of a problem. Perhaps the issue was the small size of the vessels themselves, which derived from their perceived role as swift, and somewhat expendable hunters.

Havock and Hornet built by Yarrow were 275 tons full load; Shark, Hardy and Haughty were 325 tons, Skate was 340 tons.
So yes topweight was an issue. But I can't see one twin mount weighing that much more than two singles, although the mount diameter is much larger.

Quoted from "Hood"

Havock and Hornet built by Yarrow were 275 tons full load; Shark, Hardy and Haughty were 325 tons, Skate was 340 tons.
So yes topweight was an issue. But I can't see one twin mount weighing that much more than two singles, although the mount diameter is much larger.

The mount itself may not weigh too much more, but the weight of the mount with torpedoes might. The additional weight concentrated at particular points might have required strengthening of the deck beyond what the designers of the time thought necessary or prudent. The fact that there is no documented technical reason also makes me wonder if it could merely be inertia, "If it isn't broke, don't fix it."

Friedman's BRITISH DESTROYERS pretty much echos what Hood said. The only thing I can think of is that one twin mount puts a lot more weight in one place than two single mounts that spread it out. This then requires a larger and more robust hull. I think your design is big enough that 2 twins shouldn't pose a problem...

One of the more unusual designs of the transitional period, the torpedo gunboat. This particular design is inspired by the Royal Navy's Sharpshooter class of 1892. I cannot say I am particularly fond of the result, and it demonstrates the limitations of high speed and endurance with VTE engines.


TBD, TBD Torpedo Gunboat laid down 1892

Displacement: 752 t light; 785 t standard; 880 t normal; 956 t full load

Dimensions: Length overall / water x beam x draught

198.82 ft / 196.85 ft x 23.29 ft x 9.84 ft (normal load) [60.60 m / 60.00 m x 7.10 m x 3.00 m]

Armament:

2 - 4.72" / 120 mm guns in single mounts, 52.72lbs / 23.92kg shells, 1892 Model Breech loading guns in deck mounts on centreline ends, evenly spread
4 - 1.85" / 47.0 mm guns in single mounts, 3.17lbs / 1.44kg shells, 1892 Model Quick firing guns in deck mounts on side, evenly spread
Weight of broadside 118 lbs / 54 kg
Shells per gun, main battery: 220
5 - 17.7" / 450 mm above water torpedoes

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.59" / 15 mm -

Conning tower: 1.97" / 50 mm

Machinery: Coal fired boilers, complex reciprocating steam engines, Direct drive, 2 shafts, 4,014 ihp / 2,995 Kw = 19.00 kts
Range 2,500nm at 10.00 kts
Bunker at max displacement = 171 tons (100% coal)

Complement: 80 - 105

Cost: £0.100 million / $0.399 million

Distribution of weights at normal displacement:

Armament: 15 tons, 1.7 %
Armour: 9 tons, 1.0 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 5 tons, 0.6 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 4 tons, 0.4 %
Machinery: 436 tons, 49.5 %
Hull, fittings & equipment: 243 tons, 27.6 %
Fuel, ammunition & stores: 128 tons, 14.5 %
Miscellaneous weights: 50 tons, 5.7 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 285 lbs / 129 Kg = 5.4 x 4.7 " / 120 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.15
Metacentric height 0.7 ft / 0.2 m
Roll period: 11.4 seconds
Steadiness - As gun platform (Average = 50 %): 61 %
- Recoil effect (Restricted arc if above 1.00): 0.23
Seaboat quality (Average = 1.00): 1.09

Hull form characteristics:

Hull has rise forward of midbreak
Block coefficient: 0.682
Length to Beam Ratio: 8.45 : 1
'Natural speed' for length: 14.03 kts
Power going to wave formation at top speed: 64 %
Trim (Max stability = 0, Max steadiness = 100): 56
Bow angle (Positive = bow angles forward): 5.00 degrees
Stern overhang: 0.82 ft / 0.25 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 13.12 ft / 4.00 m
- Forecastle (40 %): 12.30 ft / 3.75 m
- Mid (50 %): 11.48 ft / 3.50 m (6.56 ft / 2.00 m aft of break)
- Quarterdeck (25 %): 6.56 ft / 2.00 m
- Stern: 6.56 ft / 2.00 m
- Average freeboard: 9.52 ft / 2.90 m
Ship tends to be wet forward

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 179.4 %
- Above water (accommodation/working, high = better): 32.4 %
Waterplane Area: 3,618 Square feet or 336 Square metres
Displacement factor (Displacement / loading): 55 %
Structure weight / hull surface area: 37 lbs/sq ft or 181 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.58
- Overall: 1.00
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is extremely poor

At times it seemed that it took a minimum of "war" to turn a vessel into a warship. This design sketch is based on that of the Peruvian unprotected cruiser Lima, historically laid down in 1881 as a merchantman and converted into a warship in 1888. Her historical sister ended up in American service as the USS Topeka. While certainly unable to stand up to a regularly commissioned warship, this design might represent an auxiliary warship or wartime gunboat - or, like her exemplar, a warship for a second or third-class navy.

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TBD, TBD Unprotected Cruiser (Gunboat) laid down 1888

Displacement: 1,337 t light; 1,403 t standard; 1,700 t normal; 1,938 t full load

Dimensions: Length overall / water x beam x draught

253.51 ft / 250.00 ft x 35.10 ft x 14.99 ft (normal load) [77.27 m / 76.20 m x 10.70 m x 4.57 m]

Armament:

2 - 5.91" / 150 mm guns in single mounts, 99.89lbs / 45.31kg shells, 1888 Model Breech loading guns in deck mounts on centreline ends, evenly spread
4 - 2.17" / 55.0 mm guns in single mounts, 4.92lbs / 2.23kg shells, 1888 Model Breech loading guns in deck mounts on side, all amidships
Weight of broadside 219 lbs / 100 kg
Shells per gun, main battery: 250

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm 0.98" / 25 mm -

Conning tower: 0.98" / 25 mm

Machinery:

Coal fired boilers, complex reciprocating steam engines, Direct drive, 2 shafts, 2,630 ihp / 1,962 Kw = 16.00 kts
Range 5,000nm at 10.00 kts
Bunker at max displacement = 534 tons (100% coal)

Complement: 132 - 172

Cost: £0.139 million / $0.557 million

Distribution of weights at normal displacement:

Armament: 27 tons, 1.6 %
Armour: 13 tons, 0.7 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 10 tons, 0.6 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 3 tons, 0.2 %
Machinery: 496 tons, 29.2 %
Hull, fittings & equipment: 801 tons, 47.1 %
Fuel, ammunition & stores: 363 tons, 21.3 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 1,761 lbs / 799 Kg = 17.6 x 5.9 " / 150 mm shells or 0.6 torpedoes
Stability (Unstable if below 1.00): 1.43
Metacentric height 1.9 ft / 0.6 m
Roll period: 10.6 seconds
Steadiness - As gun platform (Average = 50 %): 100 %
- Recoil effect (Restricted arc if above 1.00): 0.16
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:

Hull has a flush deck
Block coefficient: 0.452
Length to Beam Ratio: 7.12 : 1
'Natural speed' for length: 15.81 kts
Power going to wave formation at top speed: 44 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 1.00 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 13.12 ft / 4.00 m
- Forecastle (40 %): 12.30 ft / 3.75 m
- Mid (50 %): 11.48 ft / 3.50 m
- Quarterdeck (25 %): 11.48 ft / 3.50 m
- Stern: 11.48 ft / 3.50 m
- Average freeboard: 11.98 ft / 3.65 m
Ship tends to be wet forward

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 108.2 %
- Above water (accommodation/working, high = better): 93.9 %
Waterplane Area: 5,608 Square feet or 521 Square metres
Displacement factor (Displacement / loading): 139 %
Structure weight / hull surface area: 81 lbs/sq ft or 397 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.30
- Longitudinal: 4.19
- Overall: 1.46
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Another interesting design concept of the transitional period was the so-called "Flatiron" or Rendel gunboat. The concept envisioned a very small vessel carrying a single large-caliber gun, intended to operate in coastal waters or in defense of harbors. While the type was built in substantial numbers their combat record proved very disappointing. More information can be found here.

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TBD, TBD Coastal Gunboat laid down 1881

Displacement: 237 t light; 261 t standard; 265 t normal; 268 t full load

Dimensions: Length overall / water x beam x draught

89.17 ft / 87.27 ft x 26.12 ft x 6.50 ft (normal load) [27.18 m / 26.60 m x 7.96 m x 1.98 m]

Armament:

1 - 9.45" / 240 mm guns in single mounts, 364.85lbs / 165.49kg shells, 1881 Model Breech loading gun in deck mount on centreline forward
Weight of broadside 365 lbs / 165 kg
Shells per gun, main battery: 90

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.97" / 50 mm 0.98" / 25 mm -

Armour deck: 0.98" / 25 mm, Conning tower: 1.97" / 50 mm

Machinery:

Coal fired boilers, simple reciprocating steam engines, Direct drive, 2 shafts, 127 ihp / 94 Kw = 8.50 kts
Range 600nm at 5.00 kts
Bunker at max displacement = 8 tons (100% coal)

Complement: 32 - 42

Cost: £0.049 million / $0.195 million

Distribution of weights at normal displacement:

Armament: 46 tons, 17.2 %
Armour: 44 tons, 16.6 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 11 tons, 4.2 %
- Armour Deck: 31 tons, 11.7 %
- Conning Tower: 2 tons, 0.7 %
Machinery: 16 tons, 6.0 %
Hull, fittings & equipment: 132 tons, 49.7 %
Fuel, ammunition & stores: 28 tons, 10.5 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 149 lbs / 68 Kg = 0.4 x 9.4 " / 240 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.38
Metacentric height 1.2 ft / 0.4 m
Roll period: 10.1 seconds
Steadiness - As gun platform (Average = 50 %): 100 %
- Recoil effect (Restricted arc if above 1.00): 0.81
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:

Hull has raised quarterdeck
Block coefficient: 0.626
Length to Beam Ratio: 3.34 : 1
'Natural speed' for length: 9.34 kts
Power going to wave formation at top speed: 52 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 2.25 degrees
Stern overhang: 1.64 ft / 0.50 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 6.56 ft / 2.00 m
- Forecastle (20 %): 7.38 ft / 2.25 m
- Mid (50 %): 7.38 ft / 2.25 m
- Quarterdeck (22 %): 9.84 ft / 3.00 m (7.38 ft / 2.25 m before break)
- Stern: 9.84 ft / 3.00 m
- Average freeboard: 7.86 ft / 2.40 m
Ship tends to be wet forward

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 145.8 %
- Above water (accommodation/working, high = better): 75.1 %
Waterplane Area: 1,708 Square feet or 159 Square metres
Displacement factor (Displacement / loading): 58 %
Structure weight / hull surface area: 54 lbs/sq ft or 263 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.80
- Longitudinal: 7.41
- Overall: 1.00
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
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Quoted from "BruceDuncan"

Armament:

1 - 9.45" / 240 mm guns in single mounts, 364.85lbs / 165.49kg shells, 1881 Model Breech loading gun in deck mount on centreline forward
Weight of broadside 365 lbs / 165 kg
Shells per gun, main battery: 90

For a gun this large would mount and hoist be better?

Quoted from "eltf177"

Quoted from "BruceDuncan"

Armament:

1 - 9.45" / 240 mm guns in single mounts, 364.85lbs / 165.49kg shells, 1881 Model Breech loading gun in deck mount on centreline forward
Weight of broadside 365 lbs / 165 kg
Shells per gun, main battery: 90

For a gun this large would mount and hoist be better?

Given the small size of the vessel, and its very shallow draft, I doubt that there is much space below deck for a hoist in the traditional sense. Certainly some mechanical means would be available to shift the ammunition from the magazine but I doubt that there would be automatic equipment to do so.

Quoted

Given the small size of the vessel, and its very shallow draft, I doubt that there is much space below deck for a hoist in the traditional sense. Certainly some mechanical means would be available to shift the ammunition from the magazine but I doubt that there would be automatic equipment to do so.

In 1881, not automatic equipement but hoist & chains like US monitors.

Makes sense...