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Main Archive => Navalism 3 Armed Forces => Armed Forces => New Ship Designs => Topic started by: ciders on July 23, 2010, 01:51:18 PM

Title: Saïgon Shipyards
Post by: ciders on July 23, 2010, 01:51:18 PM
First project for the Indochinese Navy : a small patrol ship, for harbours and rivers. It's inspired by a NUS ship, but it's bigger and more protected than the NUS ship.

QuoteGia-Long, Independent Indochina Patrol Ship laid down 1919 (Engine 1916)

Displacement:
   42 t light; 43 t standard; 55 t normal; 64 t full load

Dimensions: Length overall / water x beam x draught
   98,43 ft / 98,43 ft x 11,48 ft x 3,94 ft (normal load)
   30,00 m / 30,00 m x 3,50 m  x 1,20 m

Armament:
     1 - 2,24" / 57,0 mm guns in single mounts, 5,65lbs / 2,56kg shells, 1911 Model
     Quick firing gun in deck mount
     on centreline forward
     2 - 0,50" / 12,7 mm guns in single mounts, 0,06lbs / 0,03kg shells, 1911 Model
     Machine guns in deck mounts
     on centreline, evenly spread
   Weight of broadside 6 lbs / 3 kg
   Shells per gun, main battery: 200

Armour:
  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,59" / 15 mm         -               -
   2nd:   0,59" / 15 mm         -               -

  - Armour deck: 0,20" / 5 mm

Machinery:
   Petrol Internal combustion motors,
   Geared drive, 2 shafts, 329 shp / 246 Kw = 15,00 kts
   Range 2 300nm at 12,00 kts
   Bunker at max displacement = 21 tons

Complement:
   9 - 13

Cost:
   £0,008 million / $0,033 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 1,3 %
   Armour: 3 tons, 6,0 %
      - Belts: 0 tons, 0,0 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 1 tons, 1,3 %
      - Armour Deck: 3 tons, 4,7 %
      - Conning Tower: 0 tons, 0,0 %
   Machinery: 12 tons, 22,3 %
   Hull, fittings & equipment: 20 tons, 37,1 %
   Fuel, ammunition & stores: 13 tons, 24,2 %
   Miscellaneous weights: 5 tons, 9,1 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     71 lbs / 32 Kg = 12,6 x 2,2 " / 57 mm shells or 0,2 torpedoes
   Stability (Unstable if below 1.00): 1,05
   Metacentric height 0,2 ft / 0,1 m
   Roll period: 10,4 seconds
   Steadiness   - As gun platform (Average = 50 %): 100 %
         - Recoil effect (Restricted arc if above 1.00): 0,31
   Seaboat quality  (Average = 1.00): 2,00

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,433
   Length to Beam Ratio: 8,57 : 1
   'Natural speed' for length: 9,92 kts
   Power going to wave formation at top speed: 60 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 0,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      10,93 ft / 3,33 m
      - Forecastle (10 %):   6,96 ft / 2,12 m
      - Mid (50 %):      6,96 ft / 2,12 m
      - Quarterdeck (15 %):   6,96 ft / 2,12 m
      - Stern:      6,96 ft / 2,12 m
      - Average freeboard:   7,11 ft / 2,17 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 93,1 %
      - Above water (accommodation/working, high = better): 104,7 %
   Waterplane Area: 711 Square feet or 66 Square metres
   Displacement factor (Displacement / loading): 143 %
   Structure weight / hull surface area: 10 lbs/sq ft or 50 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,49
      - Longitudinal: 9,40
      - Overall: 0,66

   Caution: Hull subject to strain in open-sea
   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
Title: Re: Saïgon Shipyards
Post by: P3D on July 23, 2010, 01:54:34 PM
The X-sectional strength is below the one under destroyer rules - but the boat is too slow to build under such.
Title: Re: Saïgon Shipyards
Post by: ciders on July 23, 2010, 02:04:41 PM
Should I increase the cross-sectionnal hull strenght ?
Title: Re: Saïgon Shipyards
Post by: Sachmle on July 23, 2010, 02:35:47 PM
Quote from: ciders on July 23, 2010, 02:04:41 PM
Should I increase the cross-sectionnal hull strenght ?

I would, but I'd do it by lowering freeboard. With a 2.00 seakeeping you can afford it. Shouldn't take much, maybe 2.10 instead of 2.12 across the ship, or drop the quarterdeck then you can drop mines (granted only 5) or depth charges. (Multi purpose is good, no?)
Title: Re: Saïgon Shipyards
Post by: P3D on July 23, 2010, 02:41:18 PM
You still need 1.00 overall strength. The range is too high, bunkerage taking 50% of full displacement. The ships is kinda slow and somewhat weakly armed to act as a subchaser.
Title: Re: Saïgon Shipyards
Post by: Sachmle on July 23, 2010, 02:46:26 PM
Quote from: P3D on July 23, 2010, 02:41:18 PM
You still need 1.00 overall strength. The range is too high, bunkerage taking 50% of full displacement. The ships is kinda slow and somewhat weakly armed to act as a subchaser.

LOL...I never even looked at the overall.
Title: Re: Saïgon Shipyards
Post by: ciders on July 23, 2010, 02:58:48 PM
It's not an coastal patrol ship, but more a riverine patrol ship, in fact. It will  have to patrol in the neighborhood of Saigon and on the Mekong, not hunt RRC subs.

Title: Re: Saïgon Shipyards
Post by: Jefgte on July 23, 2010, 03:02:28 PM
Reduce the freeboard to increase stability - 1.10

Overall = 1.00


Jef   ;)
Title: Re: Saïgon Shipyards
Post by: Jefgte on July 23, 2010, 03:07:16 PM
Pas facile de faire une miniature de 42t ... ;)

( Not easy to SS a 42t miniature...    ;)   )


Jef   ;)
Title: Re: Saïgon Shipyards
Post by: ciders on July 24, 2010, 05:52:03 AM
( Dis tout de suite que mon Gia-Long est une barcasse rouillée armée par une bande d'Anglais rescapés de l'inauguration de la goelette de Bill ). ;D

Second prototype :

QuoteGia-Long, Independent Indochina Patrol Ship laid down 1919 (Engine 1916)

Displacement:
   60 t light; 62 t standard; 66 t normal; 70 t full load

Dimensions: Length overall / water x beam x draught
   114,83 ft / 114,83 ft x 11,81 ft x 3,94 ft (normal load)
   35,00 m / 35,00 m x 3,60 m  x 1,20 m

Armament:
      1 - 2,24" / 57,0 mm guns in single mounts, 5,65lbs / 2,56kg shells, 1911 Model
     Quick firing gun in deck mount
     on centreline forward
      2 - 0,50" / 12,7 mm guns in single mounts, 0,06lbs / 0,03kg shells, 1911 Model
     Machine guns in deck mounts
     on centreline, evenly spread
   Weight of broadside 6 lbs / 3 kg
   Shells per gun, main battery: 200

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,59" / 15 mm         -               -
   2nd:   0,59" / 15 mm         -               -

   - Armour deck: 0,20" / 5 mm

Machinery:
   Petrol Internal combustion motors,
   Geared drive, 2 shafts, 339 shp / 253 Kw = 15,00 kts
   Range 800nm at 12,00 kts
   Bunker at max displacement = 8 tons

Complement:
   11 - 15

Cost:
   £0,010 million / $0,039 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 1,1 %
   Armour: 4 tons, 5,8 %
      - Belts: 0 tons, 0,0 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 1 tons, 1,1 %
      - Armour Deck: 3 tons, 4,7 %
      - Conning Tower: 0 tons, 0,0 %
   Machinery: 13 tons, 19,1 %
   Hull, fittings & equipment: 37 tons, 56,6 %
   Fuel, ammunition & stores: 6 tons, 9,8 %
   Miscellaneous weights: 5 tons, 7,6 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     148 lbs / 67 Kg = 26,3 x 2,2 " / 57 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,01
   Metacentric height 0,2 ft / 0,1 m
   Roll period: 10,9 seconds
   Steadiness   - As gun platform (Average = 50 %): 66 %
         - Recoil effect (Restricted arc if above 1.00): 0,21
   Seaboat quality  (Average = 1.00): 2,00

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,433
   Length to Beam Ratio: 9,72 : 1
   'Natural speed' for length: 10,72 kts
   Power going to wave formation at top speed: 54 %
   Trim (Max stability = 0, Max steadiness = 100): 33
   Bow angle (Positive = bow angles forward): 0,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      10,93 ft / 3,33 m
      - Forecastle (15 %):   6,96 ft / 2,12 m
      - Mid (50 %):      6,96 ft / 2,12 m
      - Quarterdeck (15 %):   6,96 ft / 2,12 m
      - Stern:      6,96 ft / 2,12 m
      - Average freeboard:   7,19 ft / 2,19 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 79,7 %
      - Above water (accommodation/working, high = better): 102,8 %
   Waterplane Area: 854 Square feet or 79 Square metres
   Displacement factor (Displacement / loading): 166 %
   Structure weight / hull surface area: 16 lbs/sq ft or 78 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,77
      - Longitudinal: 10,50
      - Overall: 1,00

   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is adequate
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather






Title: Re: Saïgon Shipyards
Post by: Jefgte on July 24, 2010, 03:57:57 PM
Quote...Stability (Unstable if below 1.00): 1,01
...


- Increase beam
- Reduce freeboard
- Increase stability to 1.08 - 1.10


Jef
Title: Re: Saïgon Shipyards
Post by: ciders on July 25, 2010, 04:27:42 AM
QuoteGia-Long, Independent Indochina Patrol Ship laid down 1919 (Engine 1916)

Displacement:
   66 t light; 69 t standard; 73 t normal; 77 t full load

Dimensions: Length overall / water x beam x draught
   114,83 ft / 114,83 ft x 13,12 ft x 3,94 ft (normal load)
   35,00 m / 35,00 m x 4,00 m  x 1,20 m

Armament:
      1 - 2,24" / 57,0 mm guns in single mounts, 5,65lbs / 2,56kg shells, 1911 Model
     Quick firing gun in deck mount
     on centreline forward
      2 - 0,50" / 12,7 mm guns in single mounts, 0,06lbs / 0,03kg shells, 1911 Model
     Machine guns in deck mounts
     on centreline, evenly spread
   Weight of broadside 6 lbs / 3 kg
   Shells per gun, main battery: 200

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,59" / 15 mm         -               -
   2nd:   0,59" / 15 mm         -               -

   - Armour deck: 0,20" / 5 mm

Machinery:
   Petrol Internal combustion motors,
   Geared drive, 2 shafts, 367 shp / 274 Kw = 15,00 kts
   Range 800nm at 12,00 kts
   Bunker at max displacement = 9 tons

Complement:
   12 - 16

Cost:
   £0,011 million / $0,042 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 1,0 %
   Armour: 4 tons, 5,7 %
      - Belts: 0 tons, 0,0 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 1 tons, 1,0 %
      - Armour Deck: 3 tons, 4,7 %
      - Conning Tower: 0 tons, 0,0 %
   Machinery: 14 tons, 18,6 %
   Hull, fittings & equipment: 43 tons, 58,4 %
   Fuel, ammunition & stores: 7 tons, 9,5 %
   Miscellaneous weights: 5 tons, 6,8 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     171 lbs / 78 Kg = 30,3 x 2,2 " / 57 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,08
   Metacentric height 0,3 ft / 0,1 m
   Roll period: 10,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 66 %
         - Recoil effect (Restricted arc if above 1.00): 0,13
   Seaboat quality  (Average = 1.00): 2,00

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,433
   Length to Beam Ratio: 8,75 : 1
   'Natural speed' for length: 10,72 kts
   Power going to wave formation at top speed: 55 %
   Trim (Max stability = 0, Max steadiness = 100): 33
   Bow angle (Positive = bow angles forward): 0,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      11,78 ft / 3,59 m
      - Forecastle (10 %):   6,56 ft / 2,00 m
      - Mid (40 %):      6,56 ft / 2,00 m
      - Quarterdeck (10 %):   6,56 ft / 2,00 m
      - Stern:      6,56 ft / 2,00 m
      - Average freeboard:   6,77 ft / 2,06 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 76,5 %
      - Above water (accommodation/working, high = better): 98,8 %
   Waterplane Area: 948 Square feet or 88 Square metres
   Displacement factor (Displacement / loading): 174 %
   Structure weight / hull surface area: 20 lbs/sq ft or 98 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,94
      - Longitudinal: 7,73
      - Overall: 1,16

   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is adequate
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather