New Gran Colombian ships for 1916

[The Rock Doctor]

Let's see...

The Colombians haven't built any coastal torpedo boats in several years; they've generally taken the view that old torpedo-boats can do the coastal defense job that smaller new ones can.

Geopolitical considerations are now causing the Colombians to reconsider their position.  Smaller, more effective boats might be more appropriate to certain environments.  Therefore, a single U-class boat will be constructed and used for trials and training, at least until such time as any additional orders might be made.



Enter ship name, Enter country Enter ship type laid down 1916

Displacement:
   396 t light; 409 t standard; 451 t normal; 485 t full load

Dimensions: Length overall / water x beam x draught
   229.44 ft / 226.38 ft x 19.69 ft x 8.86 ft (normal load)
   69.93 m / 69.00 m x 6.00 m  x 2.70 m

Armament:
      2 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1916 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread
      2 - 0.31" / 8.0 mm guns in single mounts, 0.02lbs / 0.01kg shells, 1916 Model
     Breech loading guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 27 lbs / 12 kg
   Shells per gun, main battery: 250
   3 - 21.0" / 533 mm above water torpedoes

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

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 14,000 shp / 10,444 Kw = 30.02 kts
   Range 4,000nm at 10.00 kts (Bunkerage = 76 tons)

Complement:
   48 - 63

Cost:
   £0.083 million / $0.330 million

Distribution of weights at normal displacement:
   Armament: 3 tons, 0.7 %
   Armour: 3 tons, 0.7 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 3 tons, 0.7 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 241 tons, 53.4 %
   Hull, fittings & equipment: 137 tons, 30.5 %
   Fuel, ammunition & stores: 55 tons, 12.2 %
   Miscellaneous weights: 11 tons, 2.4 %
-6 t:  Three big fish
-4 t:  12 depth charges
-1 t:  Weight reserve

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     115 lbs / 52 Kg = 8.6 x 3.0 " / 76 mm shells or 0.1 torpedoes
   Stability (Unstable if below 1.00): 1.23
   Metacentric height 0.6 ft / 0.2 m
   Roll period: 10.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.11
   Seaboat quality  (Average = 1.00): 0.94

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.400
   Length to Beam Ratio: 11.50 : 1
   'Natural speed' for length: 15.05 kts
   Power going to wave formation at top speed: 69 %
   Trim (Max stability = 0, Max steadiness = 100): 53
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: -3.28 ft / -1.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      17.39 ft / 5.30 m
      - Forecastle (20 %):   14.44 ft / 4.40 m
      - Mid (40 %):      14.44 ft / 4.40 m (6.56 ft / 2.00 m aft of break)
      - Quarterdeck (15 %):   6.56 ft / 2.00 m
      - Stern:      6.56 ft / 2.00 m
      - Average freeboard:   9.95 ft / 3.03 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 181.3 %
      - Above water (accommodation/working, high = better): 52.5 %
   Waterplane Area: 2,743 Square feet or 255 Square metres
   Displacement factor (Displacement / loading): 42 %
   Structure weight / hull surface area: 21 lbs/sq ft or 102 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 2.89
      - Overall: 0.59
   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

[P3D]

Draught a bit too deep. I'd try to keep D:B ratio over 1:2.5 - 1:3.

I'd suggest 250kg per Depth Charge + associated weights.

[The Rock Doctor]

I've used one tonne per three depth charges, as suggested in the design guidelines.

I agree the draught is on the high side, but there are historical boats of generally similar dimensions.

[Jefgte]

Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Not cool for the crew & actions...


;)

[Korpen]

Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Not cool for the crew & actions...

t is cool for them, after all it is a 450ton boat, it is never going to be comfortable in heavy seas, no matter the seakeeping rating. Better to spend the weight on the things that matter for baots such as tis.

[The Rock Doctor]

I reckon that the seakeeping figure, while not great, is also not bad for her size and speed.

[Jefgte]

Did you test flushdeck hull ?

[The Rock Doctor]

I didn't.

[Jefgte]

I have tested flush deck hull (ala Flechter)...
hmmm...
Nearly identical (0.95) for seaboat quality.

;)

[P3D]

You might check my 'emergency' design which at the end did not get built. Of course, more capable being 100t heavier (about the same speed with 1916 engines)

http://www.navalism.org/index.php?topic=137.45

And could we get a final word on the destroyer speed issue? We cannot really evaluate small ships without that context.

[The Rock Doctor]

The T-class torpedo-boats will, eventually, operate as a squadron.  For now, however, their intended purpose is to function as a leader of other, older torpedo-boats, in the place of the older protected cruisers that are due to be retired.  To this end, they have long-range wireless and limited flag facilities. 

Construction will be limited to one unit per half-year for the moment, as the big capital ships are sucking up the majority of the Armada's budget.

(Yes, a block-co-efficient of 0.38 and a 12:1 L:B ratio would provide a faster ship with better seakeeping; I'm not bothering to max-min my designs.)



Enter ship name, Enter country Enter ship type laid down 1916

Displacement:
   1,482 t light; 1,541 t standard; 1,784 t normal; 1,979 t full load

Dimensions: Length overall / water x beam x draught
   389.07 ft / 385.83 ft x 33.79 ft x 11.98 ft (normal load)
   118.59 m / 117.60 m x 10.30 m  x 3.65 m

Armament:
      5 - 3.94" / 100 mm guns in single mounts, 30.51lbs / 13.84kg shells, 1916 Model
     Breech loading guns in deck mounts
     on centreline ends, majority aft, 3 raised mounts - superfiring
      1 - 2.56" / 65.0 mm guns in single mounts, 8.38lbs / 3.80kg shells, 1916 Model
     Breech loading gun in deck mount
     on centreline aft, 1 raised gun
      2 - 0.31" / 8.0 mm guns in single mounts, 0.02lbs / 0.01kg shells, 1916 Model
     Breech loading guns in deck mounts
     on side, evenly spread
   Weight of broadside 161 lbs / 73 kg
   Shells per gun, main battery: 250
   6 - 21.0" / 533 mm above water torpedoes

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

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 34,000 shp / 25,364 Kw = 32.33 kts
   Range 10,000nm at 10.00 kts (Bunkerage = 439 tons)

Complement:
   136 - 178

Cost:
   £0.330 million / $1.319 million

Distribution of weights at normal displacement:
   Armament: 20 tons, 1.1 %
   Armour: 16 tons, 0.9 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 16 tons, 0.9 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 948 tons, 53.1 %
   Hull, fittings & equipment: 407 tons, 22.8 %
   Fuel, ammunition & stores: 302 tons, 16.9 %
   Miscellaneous weights: 91 tons, 5.1 %
   -25 t:  Long-Range Wireless
   -25 t:  Fire Control
   -15 t:  Flag facilities
   -12 t:  Torpedoes
   -10 t:  Weight Reserve
   -4 t:  12 Depth Charges

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     395 lbs / 179 Kg = 12.9 x 3.9 " / 100 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.40
   Metacentric height 1.8 ft / 0.5 m
   Roll period: 10.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.12
   Seaboat quality  (Average = 1.00): 0.97

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.400
   Length to Beam Ratio: 11.42 : 1
   'Natural speed' for length: 19.64 kts
   Power going to wave formation at top speed: 61 %
   Trim (Max stability = 0, Max steadiness = 100): 72
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18.37 ft / 5.60 m
      - Forecastle (20 %):   16.40 ft / 5.00 m
      - Mid (45 %):      16.40 ft / 5.00 m (8.53 ft / 2.60 m aft of break)
      - Quarterdeck (15 %):   8.53 ft / 2.60 m
      - Stern:      8.53 ft / 2.60 m
      - Average freeboard:   12.23 ft / 3.73 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 186.1 %
      - Above water (accommodation/working, high = better): 88.8 %
   Waterplane Area: 8,026 Square feet or 746 Square metres
   Displacement factor (Displacement / loading): 64 %
   Structure weight / hull surface area: 29 lbs/sq ft or 142 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 0.82
      - Overall: 0.52
   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
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

[The Rock Doctor]

The Cesar class are just stretched, faster updates of the Saint Thomas class, optimized for escort of the Arquero class armored cruisers.  Two units will be built, with a second pair expected in the medium term.



Enter ship name, Enter country Enter ship type laid down 1916

Displacement:
   5,799 t light; 6,003 t standard; 6,654 t normal; 7,175 t full load

Dimensions: Length overall / water x beam x draught
   513.04 ft / 508.53 ft x 50.85 ft x 20.01 ft (normal load)
   156.38 m / 155.00 m x 15.50 m  x 6.10 m

Armament:
      5 - 5.51" / 140 mm guns in single mounts, 83.72lbs / 37.98kg shells, 1916 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, majority forward, 4 raised mounts - superfiring
      2 - 5.51" / 140 mm guns in single mounts, 83.72lbs / 37.98kg shells, 1916 Model
     Breech loading guns in deck mounts with hoists
     on centreline, all amidships, all raised mounts - superfiring
      2 - 2.56" / 65.0 mm guns in single mounts, 8.38lbs / 3.80kg shells, 1916 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread
      4 - 0.31" / 8.0 mm guns in single mounts, 0.02lbs / 0.01kg shells, 1916 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 603 lbs / 273 kg
   Shells per gun, main battery: 200
   6 - 21.0" / 533 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.95" / 75 mm   410.11 ft / 125.00 m   11.48 ft / 3.50 m
   Ends:   0.98" / 25 mm     98.39 ft / 29.99 m   11.48 ft / 3.50 m
     Main Belt covers 124 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.98" / 25 mm         -         0.98" / 25 mm
   2nd:   0.98" / 25 mm         -         0.98" / 25 mm
   3rd:   0.98" / 25 mm         -               -
   4th:   0.39" / 10 mm         -               -

   - Armour deck: 0.98" / 25 mm, Conning tower: 2.95" / 75 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 60,000 shp / 44,760 Kw = 30.99 kts
   Range 12,000nm at 10.00 kts (Bunkerage = 1,172 tons)

Complement:
   367 - 478

Cost:
   £0.948 million / $3.791 million

Distribution of weights at normal displacement:
   Armament: 75 tons, 1.1 %
   Armour: 947 tons, 14.2 %
      - Belts: 600 tons, 9.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 25 tons, 0.4 %
      - Armour Deck: 300 tons, 4.5 %
      - Conning Tower: 23 tons, 0.3 %
   Machinery: 2,235 tons, 33.6 %
   Hull, fittings & equipment: 2,353 tons, 35.4 %
   Fuel, ammunition & stores: 855 tons, 12.9 %
   Miscellaneous weights: 188 tons, 2.8 %
-100 t:  Fire control
-25 t:  Long range wireless
-25 t:  Command facilities
-26 t:  Weight reserve
-12 t:  Torpedoes

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     5,230 lbs / 2,372 Kg = 62.5 x 5.5 " / 140 mm shells or 0.9 torpedoes
   Stability (Unstable if below 1.00): 1.15
   Metacentric height 2.4 ft / 0.7 m
   Roll period: 13.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.31
   Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.450
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 22.55 kts
   Power going to wave formation at top speed: 57 %
   Trim (Max stability = 0, Max steadiness = 100): 65
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      25.59 ft / 7.80 m
      - Forecastle (20 %):   20.67 ft / 6.30 m
      - Mid (50 %):      20.67 ft / 6.30 m (12.80 ft / 3.90 m aft of break)
      - Quarterdeck (15 %):   12.80 ft / 3.90 m
      - Stern:      12.80 ft / 3.90 m
      - Average freeboard:   17.13 ft / 5.22 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 121.2 %
      - Above water (accommodation/working, high = better): 118.2 %
   Waterplane Area: 16,495 Square feet or 1,532 Square metres
   Displacement factor (Displacement / loading): 107 %
   Structure weight / hull surface area: 84 lbs/sq ft or 408 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.51
      - 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

[Guinness]

In the dark halls of the technical office of Confederate Naval Intelligence:

"Have you seen the specs just published for Colombia's new Cesar class?"

"You mean the one that looks virtually just like our leading candidate for the Chattanooga class's successors?"

"Yeah, those would be the ones. You think they stole it off our drawing board?"

"I sure hope not. If any brass asks, I think we should tell them we got hold of the Colombian design first."

[mentat]

2 nice designs

Only one consideration - the DDs, well look like an early DL - do you have option of a bigger calibre - maybe 4.7" or ?

They have very good range and speed - and should be very useful for a long time but the guns lack -  oomph ... :)

[The Rock Doctor]

I considered an option with 3 x 14cm, but ultimately rejected it, figuring the hull would be too lively for handling of the rounds (despite what the SS might claim). 

I could probably pick up 120mm from Iberia, but 5x4" seems like a very reasonable armament for a ship of this size.