WesWorld

After much tinkering, tweaking and getting used to the Metric System, I've finally managed to get a workable design for the first ship I plan to lay down for Siam... if you can call her a ship. They are actually a very large torpedo boat designed to act as a coastal destroyer and anti-MTB ship, with a secondary mission as a possible AA escort for the older Siamese ships. They are based very closely on an actual class of ship that Siam ordered in 1937, though I have decreased the number of torpedoes and increased the number of AA guns to suit my purposes.

An initial run of 8 is planned; more may be built if funding can be found, as Siam is very short on escorts for it's capital ships.

Surasdra, Saimese Torpedo Boat, laid down 1936

Displacement:
325 t light; 338 t standard; 377 t normal; 408 t full load

Dimensions: Length overall / water x beam x draught
229.66 ft / 225.56 ft x 19.69 ft x 7.38 ft (normal load)
70.00 m / 68.75 m x 6.00 m x 2.25 m

Armament:
3 - 3.00" / 76.2 mm guns in single mounts, 12.68lbs / 5.75kg shells, 1936 Model
Dual purpose guns in deck mounts
on centreline ends, majority aft, 2 raised mounts - superfiring
6 - 0.98" / 25.0 mm guns (2x3 guns), 0.55lbs / 0.25kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on side, all amidships
3 - 0.98" / 25.0 mm guns (1x3 guns), 0.48lbs / 0.22kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on centreline amidships
Weight of broadside 43 lbs / 19 kg
Shells per gun, main battery: 200
3 - 19.7" / 500 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.59" / 15 mm - -
2nd: 0.59" / 15 mm - -
3rd: 0.59" / 15 mm - -

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 2 shafts, 14,000 shp / 10,444 Kw = 30.82 kts
Range 2,000nm at 15.48 kts
Bunker at max displacement = 71 tons

Complement:
42 - 55

Cost:
£0.228 million / $0.914 million

Distribution of weights at normal displacement:
Armament: 6 tons, 1.5 %
Armour: 4 tons, 1.1 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 4 tons, 1.1 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 195 tons, 51.6 %
Hull, fittings & equipment: 118 tons, 31.2 %
Fuel, ammunition & stores: 52 tons, 13.8 %
Miscellaneous weights: 3 tons, 0.8 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
94 lbs / 43 Kg = 7.0 x 3.0 " / 76 mm shells or 0.1 torpedoes
Stability (Unstable if below 1.00): 1.19
Metacentric height 0.6 ft / 0.2 m
Roll period: 10.6 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.18
Seaboat quality (Average = 1.00): 0.72

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.403
Length to Beam Ratio: 11.46 : 1
'Natural speed' for length: 15.02 kts
Power going to wave formation at top speed: 71 %
Trim (Max stability = 0, Max steadiness = 100): 70
Bow angle (Positive = bow angles forward): 13.40 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 17.22 ft / 5.25 m
- Forecastle (20 %): 13.94 ft / 4.25 m
- Mid (35 %): 13.94 ft / 4.25 m (5.74 ft / 1.75 m aft of break)
- Quarterdeck (15 %): 5.74 ft / 1.75 m
- Stern: 6.56 ft / 2.00 m
- Average freeboard: 8.94 ft / 2.72 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 179.3 %
- Above water (accommodation/working, high = better): 56.0 %
Waterplane Area: 2,737 Square feet or 254 Square metres
Displacement factor (Displacement / loading): 45 %
Structure weight / hull surface area: 21 lbs/sq ft or 100 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.96
- Overall: 0.57
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

If you are having issues with metric, there is a handy little program for reference, called convert.

Convert

Hmm now on critique... well, you do have limited goals for the ship. However I would bet on a 500 ton platform you may fit larger guns, possibly better seakeeping or speed, and a very much improved survivability that would make the ship useful for a wider role.

Or you can use http://www.onlineconversion.com/.

She´s okay for a costal combatant but I´d love to see a deck plan of her. YOu put quite many guns on her and oyu may run out of deck space quite easily....

Quoted

However I would bet on a 500 ton platform you may fit larger guns, possibly better seakeeping or speed, and a very much improved survivability that would make the ship useful for a wider role.

One 28kg 120mm shell will cripple her (inflicts 65% damage).

KK: Thanks, I used Convert when I built her- handy little thing.

Quoted

Originally posted by AdmKuznetsov
One 28kg 120mm shell will cripple her (inflicts 65% damage).

As it would many minesweepers, sloops or MTB's- both in WW and in OTL. Ships like these are plentiful in OTL for smaller nations, and though the trend in WW is toward larger ships, I can't help feel that it would be detrimental to the Siamese economy to try and field enough 1000t destroyers to escort their larger ships. These ships would serve for convoy escorts and patrol craft well, at least during peacetime.

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Originally posted by HoOmAnShe´s okay for a costal combatant but I´d love to see a deck plan of her. You put quite many guns on her and you may run out of deck space quite easily....

This is the ship I based her on. As you can see, there is more than enough room on deck for what I'd like to do. The 25mm mounts are in a triangular configuration around the stack approximately where the midships 76mm mount is located in this drawing. The midships 76mm is in place of the fore torpedo mount and the aft 76mm mount is in the same place, but raised above deck level to improve gun handling in rougher seas (anything above 5-7').

I'm doubtful about the 76mm guns vs anything bigger than a sub. One of the lessons the HSF learned fairly quickly in the Great War was that even 88mm weapons were marginal for fighting other ships, which is why you see the ships that could get fitted with 105mm guns in place of their 88mms, and future classes carried 105mm's as standard.

Silly suggestion, but it could be worth Siam waiting and just buying in bulk some ex USN DD's and doing a 15% or 25% cost refit.

Quoted

Originally posted by Earl822
Silly suggestion, but it could be worth Siam waiting and just buying in bulk some ex USN DD's and doing a 15% or 25% cost refit.

Yes, it would.
I don't really wish to buy used ships, but I know I'll have to. I'm planning to scrap at least one of Siam's older capital ships (probably the Sri Ayuthia) in the next few years, and will probably use the proceeds from that to cover the refit of 4-5 imported destroyers for fleet duty, but Siam simply doesn't have the manpower to field a lot of 1000t destroyers... or a large enough fleet to justify their presence. These would serve as 'filler' to cover the more mundane patrol duties, while still having the ability to be used defensively in a pinch.

Quoted

Originally posted by Hrolf Hakonson
I'm doubtful about the 76mm guns vs anything bigger than a sub. One of the lessons the HSF learned fairly quickly in the Great War was that even 88mm weapons were marginal for fighting other ships, which is why you see the ships that could get fitted with 105mm guns in place of their 88mms, and future classes carried 105mm's as standard.

Against anything bigger than a sub or an MTB, a 3" gun is generally too small, true. I might attempt to mount 2x1x105mm on her instead.

Quoted

Originally posted by Carthaginian

Quoted

Originally posted by Earl822
Silly suggestion, but it could be worth Siam waiting and just buying in bulk some ex USN DD's and doing a 15% or 25% cost refit.

Yes, it would.
I don't really wish to buy used ships, but I know I'll have to. I'm planning to scrap at least one of Siam's older capital ships (probably the Sri Ayuthia) in the next few years, and will probably use the proceeds from that to cover the refit of 4-5 imported destroyers for fleet duty, but Siam simply doesn't have the manpower to field a lot of 1000t destroyers... or a large enough fleet to justify their presence. These would serve as 'filler' to cover the more mundane patrol duties, while still having the ability to be used defensively in a pinch.

Make an offer on the Sampson class......

Hey! US Destroyers go to Mexico to retire...

If Siam is interested Australia does have 4 Thornycroft V class DDs available.

*looks through Siam's encyclopedia*

You want to scrap your most powerful warship? Well if you really want to get rid of her Mexico would be willing to buy her.


The TB looks pretty good, but Siam uses 100mm, 37mm, and 20mm guns. I would suggest a pair of 100m, a twin 37mm, and replacing the triple 25mm with twin 20mm guns.

Quoted

Originally posted by Desertfox
*looks through Siam's encyclopedia*

You want to scrap your most powerful warship? Well if you really want to get rid of her Mexico would be willing to buy her.

Funny, I thought the Maeklong was the most powerful Siamese warship. Meh, who knows?

Im also looking through Siam's encyclopedia

Quoted

The TB looks pretty good, but Siam uses 100mm, 37mm, and 20mm guns. I would suggest a pair of 100m, a twin 37mm, and replacing the triple 25mm with twin 20mm guns.

Ratanakosin class, Siamese (ex-Italian) Destroyers laid down 1915

These shipa have 76,2mm guns so it is an regular Siamese gun caliber, it is a good caliber against small surface combatants and it also have a good rate of fire against aircraft. 76,2mm caliber gives 3 heavy anti aircraft guns/ship against 2 with 100mm.

The problem with 76mm guns versus aircraft is that while the rate of fire is good, the effectiveness with time-fuzed HE (what they'd be using) is low because of the small shell size.

Quoted

Originally posted by Hrolf Hakonson
The problem with 76mm guns versus aircraft is that while the rate of fire is good, the effectiveness with time-fuzed HE (what they'd be using) is low because of the small shell size.

Actually, from the tables here it can be seen that the 3"/50 is a better AA gun than the 5"/38, probably due to the higher muzzle velocity. Of course, the small sample size might be skewing things.

Quoted

Originally posted by Desertfox
*looks through Siam's encyclopedia*
You want to scrap your most powerful warship?

Whoops, that was a mistake.
It was the Maeklong I wanted to scrap... got the two's seaboat qualities mixed up. What I'm after is the fact that I have a tiny navy with poorly balanced forces. I've got 1 heavy cruiser, one light cruiser, an armored cruiser, and a slow light cruiser. I think that ditching the wallowing monster will allow me to build up my escort fleet a bit, protecting my other ships.

Quoted

Originally posted by DesertfoxThe TB looks pretty good, but Siam uses 100mm, 37mm, and 20mm guns. I would suggest a pair of 100m, a twin 37mm, and replacing the triple 25mm with twin 20mm guns.

I checked and found a 76mm gun in the encyclopedia prior to designing the vessel. I could be convinced to change the AA gun mounts to 20mm triples.

Quoted

Originally posted by Hrolf HakonsonThe problem with 76mm guns versus aircraft is that while the rate of fire is good, the effectiveness with time-fuzed HE (what they'd be using) is low because of the small shell size.

They are able to be trained faster, are easier to load and fire and are (important for Siam) less expensive to make. These factors influenced their choice. I could go with a 2x1x100mm, 1x2x37mm, 3x3x20mm layout, though- but only if forced to.

Quoted

Whoops, that was a mistake.
It was the Maeklong I wanted to scrap... got the two's seaboat qualities mixed up. What I'm after is the fact that I have a tiny navy with poorly balanced forces. I've got 1 heavy cruiser, one light cruiser, an armored cruiser, and a slow light cruiser. I think that ditching the wallowing monster will allow me to build up my escort fleet a bit, protecting my other ships.

Probably a bad idea. Steel is expensive, manpower is free (in WW terms). That ship is worth 2 years of building material, and scrapping her will only net around 2,000 tons.

Quoted

They are able to be trained faster, are easier to load and fire and are (important for Siam) less expensive to make . These factors influenced their choice. I could go with a 2x1x100mm, 1x2x37mm, 3x3x20mm layout, though- but only if forced to.

Again in our rules that doesn't matter, only the ship's light tonnage is taken into account. I prefer the 100mm only because they are better against destroyers. The main weapon choice depends on what your expected oposition is. Against subs, MTBs, and planes the 76 is probably better, but agianst destroyers the 100mm is better.

Siam does have a strong airforce, and the French don't seem to have many MTBs, but do have big destroyers. Hence I would prefer the 100mm.

Quoted

Originally posted by DesertfoxProbably a bad idea. Steel is expensive, manpower is free (in WW terms). That ship is worth 2 years of building material, and scrapping her will only net around 2,000 tons.

Well, she could be put up for sale as well... as long as she draws me enough of a profit to justify it. I need destroyers, torpedo craft and other sundry attrition units if I'm going to make a small navy work. Capital ships are of rather limited use without escorts to protect them, and I have more than enough of them as it is.

Quoted

Originally posted by DesertfoxAgain in our rules that doesn't matter, only the ship's light tonnage is taken into account. I prefer the 100mm only because they are better against destroyers. The main weapon choice depends on what your expected oposition is. Against subs, MTBs, and planes the 76 is probably better, but agianst destroyers the 100mm is better.

Thus why I kept the 76mm over the 100mm. The ships are going to be doing much more AA escort work than they are anti-destroyer ops. I'll buy some real DD's for screening duties.

Quoted

Originally posted by DesertfoxSiam does have a strong airforce, and the French don't seem to have many MTBs, but do have big destroyers. Hence I would prefer the 100mm.

Aircraft against DD's is a good thing, and I don't have to go too far beyond my territory to secure my interests. Siam will probably continue to invest in aircraft for anti-ship work to combat the superior number of light ships a possible adversary might field.

And, as for something bigger, how does this look as a companion? I could put out 2 per year with my current infrastructure, and after getting my budget current, I could field two of them to serve as 'flotilla leaders' for my torpedo boats by the end of 1935.

Displacement:
800 t light; 835 t standard; 956 t normal; 1,053 t full load

Dimensions: Length overall / water x beam x draught
367.45 ft / 360.89 ft x 32.81 ft x 6.99 ft (normal load)
112.00 m / 110.00 m x 10.00 m x 2.13 m

Armament:
3 - 3.94" / 100 mm guns in single mounts, 30.86lbs / 14.00kg shells, 1935 Model
Dual purpose guns in deck mounts
on centreline ends, majority aft, 2 raised mounts - superfiring
2 - 3.94" / 100 mm guns in single mounts, 30.86lbs / 14.00kg shells, 1935 Model
Dual purpose guns in deck mounts
on side, all forward, all raised mounts - superfiring
4 - 1.46" / 37.0 mm guns (2x2 guns), 1.65lbs / 0.75kg shells, 1935 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
18 - 0.79" / 20.0 mm guns (6x3 guns), 0.22lbs / 0.10kg shells, 1935 Model
Breech loading guns in deck mounts
on side, all amidships, 4 raised mounts - superfiring
Weight of broadside 165 lbs / 75 kg
Shells per gun, main battery: 150
5 - 19.7" / 500 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - -
2nd: 0.98" / 25 mm - -
3rd: 0.59" / 15 mm - -
4th: 0.59" / 15 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 20,000 shp / 14,920 Kw = 30.91 kts
Range 3,000nm at 16.78 kts
Bunker at max displacement = 217 tons

Complement:
85 - 111

Cost:
£0.534 million / $2.137 million

Distribution of weights at normal displacement:
Armament: 20 tons, 2.1 %
Armour: 13 tons, 1.4 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 13 tons, 1.4 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 427 tons, 44.7 %
Hull, fittings & equipment: 292 tons, 30.5 %
Fuel, ammunition & stores: 156 tons, 16.3 %
Miscellaneous weights: 48 tons, 5.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
320 lbs / 145 Kg = 10.5 x 3.9 " / 100 mm shells or 0.3 torpedoes
Stability (Unstable if below 1.00): 1.46
Metacentric height 1.8 ft / 0.5 m
Roll period: 10.3 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.10
Seaboat quality (Average = 1.00): 0.74

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.404
Length to Beam Ratio: 11.00 : 1
'Natural speed' for length: 19.00 kts
Power going to wave formation at top speed: 59 %
Trim (Max stability = 0, Max steadiness = 100): 68
Bow angle (Positive = bow angles forward): 17.10 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.33 ft / 6.50 m
- Forecastle (25 %): 15.58 ft / 4.75 m
- Mid (35 %): 14.76 ft / 4.50 m (6.56 ft / 2.00 m aft of break)
- Quarterdeck (10 %): 6.56 ft / 2.00 m
- Stern: 6.56 ft / 2.00 m
- Average freeboard: 10.25 ft / 3.13 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 166.3 %
- Above water (accommodation/working, high = better): 96.1 %
Waterplane Area: 7,307 Square feet or 679 Square metres
Displacement factor (Displacement / loading): 70 %
Structure weight / hull surface area: 27 lbs/sq ft or 134 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.56
- Longitudinal: 0.58
- Overall: 0.56
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is adequate
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather