Laksmanavati designs

Jeremy · January 15, 2025, 07:54:55 PM

1500T, Laksamanavati DD1928 laid down 1928

Displacement:
1,500 t light; 1,571 t standard; 1,806 t normal; 1,995 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(384.40 ft / 380.58 ft) x 32.81 ft x (12.66 / 13.52 ft)
(117.16 m / 116.00 m) x 10.00 m x (3.86 / 4.12 m)

Armament:
5 - 4.33" / 110 mm 45.0 cal guns - 40.96lbs / 18.58kg shells, 250 per gun
Quick firing guns in deck mounts, 1928 Model
5 x Single mounts on centreline ends, majority aft
2 raised mounts - superfiring
6 - 1.57" / 40.0 mm 39.0 cal guns - 1.85lbs / 0.84kg shells, 900 per gun
Anti-air guns in deck mounts, 1928 Model
6 x Single mounts on side ends, majority forward
2 raised mounts - superfiring
12 - 0.47" / 12.0 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 2,000 per gun
Machine guns in deck mounts, 1928 Model
6 x Twin mounts on side ends, majority forward
6 raised mounts
Weight of broadside 217 lbs / 98 kg

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - -
2nd: 0.39" / 10 mm - -
3rd: 0.39" / 10 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 35,200 shp / 26,259 Kw = 32.50 kts
Range 12,000nm at 10.00 kts
Bunker at max displacement = 424 tons

Complement:
138 - 180

Cost:
£0.729 million / $2.914 million

Distribution of weights at normal displacement:
Armament: 40 tons, 2.2 %
- Guns: 40 tons, 2.2 %
Armour: 18 tons, 1.0 %
- Armament: 18 tons, 1.0 %
Machinery: 910 tons, 50.4 %
Hull, fittings & equipment: 430 tons, 23.8 %
Fuel, ammunition & stores: 306 tons, 17.0 %
Miscellaneous weights: 102 tons, 5.6 %
- Hull below water: 15 tons
- On freeboard deck: 58 tons
- Above deck: 29 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
470 lbs / 213 Kg = 11.6 x 4.3 " / 110 mm shells or 0.3 torpedoes
Stability (Unstable if below 1.00): 1.19
Metacentric height 1.3 ft / 0.4 m
Roll period: 12.1 seconds
Steadiness - As gun platform (Average = 50 %): 80 %
- Recoil effect (Restricted arc if above 1.00): 0.27
Seaboat quality (Average = 1.00): 1.16

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.400 / 0.414
Length to Beam Ratio: 11.60 : 1
'Natural speed' for length: 19.51 kts
Power going to wave formation at top speed: 61 %
Trim (Max stability = 0, Max steadiness = 100): 69
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 21.65 ft / 6.60 m, 18.04 ft / 5.50 m
- Forward deck: 30.00 %, 18.04 ft / 5.50 m, 16.73 ft / 5.10 m
- Aft deck: 35.00 %, 8.86 ft / 2.70 m, 8.86 ft / 2.70 m
- Quarter deck: 15.00 %, 8.86 ft / 2.70 m, 9.51 ft / 2.90 m
- Average freeboard: 13.59 ft / 4.14 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 170.8 %
- Above water (accommodation/working, high = better): 135.7 %
Waterplane Area: 7,686 Square feet or 714 Square metres
Displacement factor (Displacement / loading): 75 %
Structure weight / hull surface area: 30 lbs/sq ft or 148 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.28
- Overall: 0.54
Cramped machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform

Fittings:
-4 t: Fire control (1918) (above deck)
-25 t: L/R wireless (above deck)
-48 t: 4x3 21" TT (on deck)
-15 t: Enhanced hydrophone package (vital)
-5 t: 25x 195 kg DC (on deck)
-5 t: Weight reserve (above deck)

Trial Speed: 33 kt
Bonus: 0.5
Range: 13200 (geared bonus)

The Rock Doctor · January 15, 2025, 08:03:35 PM

The DD trial speeds seem high - we usually get a knot or two when we run the app.

Jeremy · January 15, 2025, 08:14:09 PM

Quote from: The Rock Doctor on January 15, 2025, 08:03:35 PMThe DD trial speeds seem high - we usually get a knot or two when we run the app.

I'm dumb. I entered the machine tonnage, not the percentage.

What do the trial speeds and bonus represent, anyway?

Jefgte · January 16, 2025, 03:31:44 AM

Quote...What do the trial speeds and bonus represent, anyway?

Speed attack !!!

https://www.bing.com/videos/riverview/relatedvideo?q=ben+hur+bataille+navale&mid=78709BA28E8E4EDECF1D78709BA28E8E4EDECF1D&FORM=VIRE

Jefgte · January 16, 2025, 06:13:04 AM

1500T, Laksamanavati DD1928 laid down 1928

From: Rules \ Ship Design Guidelines

Enter Speed and Machinery Weight and Light Displacement from SS2 report below, and click "Calculate". Results appear in results fields below.

SpringSharp Speed:
32.5
Machinery Weight %
(example: "55.5"):
50.4
Light Displacement (tons):
1500
Round to the Half Knot?

Results:
Trial Speed: 33
Bonus: 0.5

Jeremy · January 16, 2025, 08:08:44 AM

Quote from: Jefgte on January 16, 2025, 03:31:44 AM
Quote...What do the trial speeds and bonus represent, anyway?

Speed attack !!!

https://www.bing.com/videos/riverview/relatedvideo?q=ben+hur+bataille+navale&mid=78709BA28E8E4EDECF1D78709BA28E8E4EDECF1D&FORM=VIRE

Sorry. That didn't really help

I mean, I know what a trial speed is, but why is important that we calculate that?

The Rock Doctor · January 16, 2025, 09:21:30 AM

Springsharp was built to model capital ships. Its model doesn't do well with small, fast ships with lightweight machinery and tends to under-estimate the speed of such ships for any given powerplant.

Our trial speed app is an attempt to patch that up somewhat. Though I personally tend to forget it's there.

Jeremy · January 18, 2025, 07:41:04 PM

Light minesweeper with limited minelaying and ASW capabilities

Minesweeper, Laksmanavati 1916 laid down 1916

Displacement:
400 t light; 420 t standard; 485 t normal; 536 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(167.82 ft / 160.76 ft) x 22.97 ft x (9.19 / 9.92 ft)
(51.15 m / 49.00 m) x 7.00 m x (2.80 / 3.02 m)

Armament:
1 - 4.33" / 110 mm 45.0 cal gun - 40.96lbs / 18.58kg shells, 250 per gun
Quick firing gun in deck mount, 1916 Model
1 x Single mount on centreline, forward deck forward
4 - 1.57" / 40.0 mm 39.0 cal guns - 1.85lbs / 0.84kg shells, 900 per gun
Anti-air guns in deck mounts, 1916 Model
2 x Single mounts on sides, forward deck aft
1 x Twin mount on centreline, aft deck aft
1 raised mount
4 - 0.47" / 12.0 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 4,000 per gun
Machine guns in deck mounts, 1916 Model
4 x Single mounts on sides, aft evenly spread
2 raised mounts
Weight of broadside 49 lbs / 22 kg

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - -
2nd: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 2 shafts, 2,413 shp / 1,800 Kw = 18.19 kts
Range 6,000nm at 10.00 kts
Bunker at max displacement = 116 tons

Complement:
51 - 67

Cost:
£0.048 million / $0.191 million

Distribution of weights at normal displacement:
Armament: 9 tons, 1.9 %
- Guns: 9 tons, 1.9 %
Armour: 4 tons, 0.9 %
- Armament: 4 tons, 0.9 %
Machinery: 90 tons, 18.6 %
Hull, fittings & equipment: 185 tons, 38.2 %
Fuel, ammunition & stores: 84 tons, 17.4 %
Miscellaneous weights: 112 tons, 23.1 %
- Hull below water: 5 tons
- On freeboard deck: 87 tons
- Above deck: 20 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,023 lbs / 464 Kg = 25.2 x 4.3 " / 110 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 0.7 ft / 0.2 m
Roll period: 11.9 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.19
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.500 / 0.512
Length to Beam Ratio: 7.00 : 1
'Natural speed' for length: 12.68 kts
Power going to wave formation at top speed: 64 %
Trim (Max stability = 0, Max steadiness = 100): 25
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 3.94 ft / 1.20 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 17.72 ft / 5.40 m, 17.72 ft / 5.40 m
- Forward deck: 20.00 %, 17.72 ft / 5.40 m, 17.72 ft / 5.40 m
- Aft deck: 45.00 %, 9.84 ft / 3.00 m, 9.84 ft / 3.00 m
- Quarter deck: 15.00 %, 9.84 ft / 3.00 m, 9.84 ft / 3.00 m
- Average freeboard: 12.99 ft / 3.96 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 68.9 %
- Above water (accommodation/working, high = better): 112.7 %
Waterplane Area: 2,460 Square feet or 229 Square metres
Displacement factor (Displacement / loading): 151 %
Structure weight / hull surface area: 31 lbs/sq ft or 150 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.75
- Longitudinal: 12.55
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Adequate accommodation and workspace room
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Fittings:
-2 t: 1918 Fire control (above deck)
-1 t: Spotlight (above deck)
-50 t: Provision for mines (on deck)
-25 t: Minesweeping gear (on deck)
-5 t: 50x 90kg DC (on deck)
-5 t: Basic hydrophone (vital)
-17 + 7 t: Weight reserve (above deck + on deck)

Jeremy · January 18, 2025, 07:42:59 PM

An upgrade from the 1920 minesweeper with less, but heavier DC. She loses a twin AA mount however

Minesweeper, Laksmanavati 1924 laid down 1924

Displacement:
251 t light; 262 t standard; 284 t normal; 301 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(121.89 ft / 114.83 ft) x 21.98 ft x (7.87 / 8.24 ft)
(37.15 m / 35.00 m) x 6.70 m x (2.40 / 2.51 m)

Armament:
1 - 4.33" / 110 mm 45.0 cal gun - 40.96lbs / 18.58kg shells, 170 per gun
Quick firing gun in deck mount, 1924 Model
1 x Single mount on centreline, forward deck forward
2 - 1.57" / 40.0 mm 39.0 cal guns - 1.85lbs / 0.84kg shells, 900 per gun
Anti-air guns in deck mounts, 1924 Model
2 x Single mounts on sides, forward deck centre
4 - 0.47" / 12.0 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 2,000 per gun
Machine guns in deck mounts, 1924 Model
2 x Single mounts on sides, forward deck centre
2 raised mounts
2 x Single mounts on sides, aft deck aft
2 raised mounts
Weight of broadside 45 lbs / 20 kg

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - -
2nd: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 1,273 shp / 950 Kw = 16.01 kts
Range 3,000nm at 10.00 kts
Bunker at max displacement = 39 tons

Complement:
33 - 44

Cost:
£0.052 million / $0.210 million

Distribution of weights at normal displacement:
Armament: 8 tons, 3.0 %
- Guns: 8 tons, 3.0 %
Armour: 4 tons, 1.3 %
- Armament: 4 tons, 1.3 %
Machinery: 42 tons, 14.8 %
Hull, fittings & equipment: 115 tons, 40.3 %
Fuel, ammunition & stores: 33 tons, 11.8 %
Miscellaneous weights: 82 tons, 28.9 %
- Hull below water: 5 tons
- On freeboard deck: 65 tons
- Above deck: 12 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
792 lbs / 359 Kg = 19.5 x 4.3 " / 110 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.13
Metacentric height 0.6 ft / 0.2 m
Roll period: 11.5 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.23
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.500 / 0.507
Length to Beam Ratio: 5.22 : 1
'Natural speed' for length: 10.72 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 25
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 3.94 ft / 1.20 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 17.72 ft / 5.40 m, 15.75 ft / 4.80 m
- Forward deck: 40.00 %, 15.75 ft / 4.80 m, 15.75 ft / 4.80 m
- Aft deck: 25.00 %, 7.87 ft / 2.40 m, 7.87 ft / 2.40 m
- Quarter deck: 15.00 %, 7.87 ft / 2.40 m, 7.87 ft / 2.40 m
- Average freeboard: 12.76 ft / 3.89 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 60.0 %
- Above water (accommodation/working, high = better): 123.5 %
Waterplane Area: 1,682 Square feet or 156 Square metres
Displacement factor (Displacement / loading): 148 %
Structure weight / hull surface area: 28 lbs/sq ft or 137 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.70
- Longitudinal: 24.43
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Excellent accommodation and workspace room
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Fittings:
-1 t: 1918 Fire control (above deck)
-1 t: 1x spotlight (above deck)
-25 t: Provision for mines (on deck)
-25 t: Minesweeping gear (on deck)
-10 t: 25x 195kg DC (on deck)
-5 t: Basic hydrophone (vital)
-12 + 5 t: Weight reserve (above deck + on deck)

Range: 3300 nm (geared bonus)

Jeremy · January 18, 2025, 07:45:38 PM

Using the same hull as the 1924 model, the 1928 version adds back the twin AA mount on the after deck and updates the hydrophones

Minesweeper, Laksmanavati 1928 laid down 1928

Displacement:
247 t light; 263 t standard; 284 t normal; 301 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(121.89 ft / 114.83 ft) x 21.98 ft x (7.87 / 8.22 ft)
(37.15 m / 35.00 m) x 6.70 m x (2.40 / 2.51 m)

Armament:
1 - 4.33" / 110 mm 45.0 cal gun - 40.96lbs / 18.58kg shells, 250 per gun
Quick firing gun in deck mount, 1928 Model
1 x Single mount on centreline, forward deck forward
4 - 1.57" / 40.0 mm 39.0 cal guns - 1.85lbs / 0.84kg shells, 900 per gun
Anti-air guns in deck mounts, 1928 Model
2 x Single mounts on sides, forward deck centre
1 x Twin mount on centreline, aft deck aft
1 raised mount
4 - 0.47" / 12.0 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 4,000 per gun
Machine guns in deck mounts, 1928 Model
2 x Single mounts on sides, forward deck centre
2 raised mounts
2 x Single mounts on sides, aft deck aft
2 raised mounts
Weight of broadside 49 lbs / 22 kg

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - -
2nd: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 1,273 shp / 950 Kw = 16.01 kts
Range 3,000nm at 10.00 kts
Bunker at max displacement = 38 tons

Complement:
33 - 44

Cost:
£0.064 million / $0.256 million

Distribution of weights at normal displacement:
Armament: 9 tons, 3.2 %
- Guns: 9 tons, 3.2 %
Armour: 4 tons, 1.5 %
- Armament: 4 tons, 1.5 %
Machinery: 40 tons, 14.0 %
Hull, fittings & equipment: 106 tons, 37.5 %
Fuel, ammunition & stores: 37 tons, 12.9 %
Miscellaneous weights: 88 tons, 31.0 %
- Hull below water: 15 tons
- On freeboard deck: 63 tons
- Above deck: 10 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
707 lbs / 321 Kg = 17.4 x 4.3 " / 110 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.16
Metacentric height 0.7 ft / 0.2 m
Roll period: 11.2 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.26
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.500 / 0.507
Length to Beam Ratio: 5.22 : 1
'Natural speed' for length: 10.72 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 25
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 3.94 ft / 1.20 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 17.72 ft / 5.40 m, 15.75 ft / 4.80 m
- Forward deck: 40.00 %, 15.75 ft / 4.80 m, 15.75 ft / 4.80 m
- Aft deck: 25.00 %, 7.87 ft / 2.40 m, 7.87 ft / 2.40 m
- Quarter deck: 15.00 %, 7.87 ft / 2.40 m, 7.87 ft / 2.40 m
- Average freeboard: 12.76 ft / 3.89 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 63.2 %
- Above water (accommodation/working, high = better): 123.5 %
Waterplane Area: 1,682 Square feet or 156 Square metres
Displacement factor (Displacement / loading): 145 %
Structure weight / hull surface area: 26 lbs/sq ft or 128 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.65
- Longitudinal: 22.80
- Overall: 0.93
Caution: Hull subject to strain in open-sea
Excellent machinery, storage, compartmentation space
Excellent accommodation and workspace room
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Fittings:
-1 t: 1918 Fire control (above deck)
-1 t: 1x spotlight (above deck)
-25 t: Provision for mines (on deck)
-25 t: Minesweeping gear (on deck)
-10 t: 25x 195kg DC (on deck)
-15 t: Enhanced hydrophone package (vital)
-8 + 3 t: Weight reserve (above deck + on deck)

Range: 3300 nm (geared bonus)

Jeremy · January 20, 2025, 04:13:31 PM

SV-1 Bandar, Laksmanavati Survey ship laid down 1912

Displacement:
730 t light; 758 t standard; 901 t normal; 1,015 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(213.81 ft / 206.69 ft) x 29.53 ft x (10.50 / 11.49 ft)
(65.17 m / 63.00 m) x 9.00 m x (3.20 / 3.50 m)

Armament:
1 - 4.33" / 110 mm 45.0 cal gun - 40.96lbs / 18.58kg shells, 250 per gun
Quick firing gun in deck mount, 1912 Model
1 x Single mount on centreline, forward deck forward
4 - 1.57" / 40.0 mm 39.0 cal guns - 1.85lbs / 0.84kg shells, 900 per gun
Anti-air guns in deck mounts, 1912 Model
1 x Twin mount on centreline, forward deck forward
1 raised mount
1 x Twin mount on centreline, aft deck aft
1 raised mount
4 - 0.47" / 12.0 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 2,000 per gun
Machine guns in deck mounts, 1912 Model
4 x Single mounts on sides, evenly spread
Weight of broadside 49 lbs / 22 kg

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - -
2nd: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 2 shafts, 4,624 shp / 3,450 Kw = 19.98 kts
Range 8,000nm at 10.00 kts
Bunker at max displacement = 258 tons

Complement:
81 - 106

Cost:
£0.054 million / $0.216 million

Distribution of weights at normal displacement:
Armament: 9 tons, 1.0 %
- Guns: 9 tons, 1.0 %
Armour: 4 tons, 0.4 %
- Armament: 4 tons, 0.4 %
Machinery: 184 tons, 20.5 %
Hull, fittings & equipment: 323 tons, 35.9 %
Fuel, ammunition & stores: 171 tons, 19.0 %
Miscellaneous weights: 210 tons, 23.3 %
- Hull above water: 60 tons
- On freeboard deck: 90 tons
- Above deck: 60 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,641 lbs / 744 Kg = 40.4 x 4.3 " / 110 mm shells or 0.8 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 1.0 ft / 0.3 m
Roll period: 12.4 seconds
Steadiness - As gun platform (Average = 50 %): 72 %
- Recoil effect (Restricted arc if above 1.00): 0.09
Seaboat quality (Average = 1.00): 1.80

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.492 / 0.507
Length to Beam Ratio: 7.00 : 1
'Natural speed' for length: 14.38 kts
Power going to wave formation at top speed: 62 %
Trim (Max stability = 0, Max steadiness = 100): 40
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 3.94 ft / 1.20 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 18.04 ft / 5.50 m, 13.12 ft / 4.00 m
- Forward deck: 50.00 %, 13.12 ft / 4.00 m, 13.12 ft / 4.00 m
- Aft deck: 15.00 %, 13.12 ft / 4.00 m, 13.12 ft / 4.00 m
- Quarter deck: 15.00 %, 13.12 ft / 4.00 m, 13.12 ft / 4.00 m
- Average freeboard: 13.52 ft / 4.12 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 78.0 %
- Above water (accommodation/working, high = better): 124.6 %
Waterplane Area: 4,037 Square feet or 375 Square metres
Displacement factor (Displacement / loading): 149 %
Structure weight / hull surface area: 40 lbs/sq ft or 196 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.84
- Longitudinal: 6.11
- Overall: 1.03
Excellent machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Fittings:
-1 t: 1918 fire control (above deck)
-25 t: L/R wireless (above deck)
-10 t: Night fighting doodads (above deck)
-60 + 90 t: Survey facilities & equipment (hull + on deck)
-24 t: Weight reserve (above deck)

Jeremy · January 24, 2025, 09:16:53 PM

(Saving this design for a possible real warship in the future)

SC-1, Laksmanavati Subchaser laid down 1922

A coastal subchaser built to mercantile standards. A 3" gun would be nice but...the RLN has none

(Guns, magazines, DC, DC throwers = 6.91, 2% of light tonnage = 7)

Displacement:
   350 t light; 360 t standard; 374 t normal; 385 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (173.15 ft / 170.60 ft) x 23.62 ft x (5.91 / 6.05 ft)
   (52.78 m / 52.00 m) x 7.20 m x (1.80 / 1.84 m)

Armament:
2 - 1.57" / 40.0 mm 39.0 cal guns - 1.85lbs / 0.84kg shells, 900 per gun
     Anti-air guns in deck mount, 1922 Model
     1 x Twin mount on centreline, forward deck forward
2 - 0.47" / 12.0 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 2,000 per gun
     Machine guns in deck mounts, 1922 Model
     2 x Single mounts on sides amidships
Weight of broadside 4 lbs / 2 kg

Machinery:
   Diesel Internal combustion motors,
   Geared drive, 1 shaft, 3,787 shp / 2,825 Kw = 21.00 kts
   Range 1,000nm at 12.00 kts
   Bunker at max displacement = 26 tons

Complement:
   42 - 55

Cost:
   £0.083 million / $0.333 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 0.2 %
     - Guns: 1 tons, 0.2 %
   Machinery: 128 tons, 34.3 %
   Hull, fittings & equipment: 152 tons, 40.6 %
   Fuel, ammunition & stores: 24 tons, 6.3 %
   Miscellaneous weights: 69 tons, 18.4 %
     - Hull below water: 40 tons
     - Hull above water: 12 tons
     - On freeboard deck: 12 tons
     - Above deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     380 lbs / 172 Kg = 194.5 x 1.6 " / 40 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 0.8 ft / 0.2 m
   Roll period: 11.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 64 %
         - Recoil effect (Restricted arc if above 1.00): 0.01
   Seaboat quality (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.550 / 0.553
   Length to Beam Ratio: 7.22 : 1
   'Natural speed' for length: 13.06 kts
   Power going to wave formation at top speed: 69 %
   Trim (Max stability = 0, Max steadiness = 100): 64
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
     - Forecastle:   20.00 %, 14.44 ft / 4.40 m, 11.81 ft / 3.60 m
     - Forward deck:   30.00 %, 11.81 ft / 3.60 m, 9.19 ft / 2.80 m
     - Aft deck:   35.00 %, 9.19 ft / 2.80 m, 9.19 ft / 2.80 m
     - Quarter deck:   15.00 %, 9.19 ft / 2.80 m, 9.19 ft / 2.80 m
     - Average freeboard:      10.31 ft / 3.14 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 127.7 %
      - Above water (accommodation/working, high = better): 121.1 %
   Waterplane Area: 2,728 Square feet or 253 Square metres
   Displacement factor (Displacement / loading): 114 %
   Structure weight / hull surface area: 30 lbs/sq ft or 148 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.85
      - Longitudinal: 4.49
      - Overall: 1.01
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Fittings:
-38 t: Diesel engines (vital)
-2 t: 2x Thornycroft DC throwers (on deck)
-2 t: 10x 195 kg DC (on deck)
-5 t: Basic hydrophones (hull)
-2 + 10 + 7 + 2 t: Weight reserve (above deck + on deck + hull + vital)

Range: 1850 (geared drive + diesel engines)

TacCovert4 · January 25, 2025, 01:08:45 AM

Generally the rule is to not make a 'cheap warship' using mercantile rules. However, the gun armament is so anemic, that even with the DC throwers and DC you're still well under 2%, so far under 2% that I think this would qualify as a mercantile-standard civilian vessel.....almost a somewhat armed trawler or more likely a revenue cutter of some sort.

Jeremy · January 25, 2025, 06:36:19 AM

Quote from: TacCovert4 on January 25, 2025, 01:08:45 AMGenerally the rule is to not make a 'cheap warship' using mercantile rules. However, the gun armament is so anemic, that even with the DC throwers and DC you're still well under 2%, so far under 2% that I think this would qualify as a mercantile-standard civilian vessel.....almost a somewhat armed trawler or more likely a revenue cutter of some sort.

Armed trawler is basically what I was going for. The RLN realized there was a capability gap and filled it with cheap civilian vessels of dubious capability. They likely get replaced with real warships shortly

Jefgte · January 25, 2025, 03:32:00 PM

Right it's a armed trawler.
But 21kts is fast for a trawler.