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.
(http://img.photobucket.com/albums/v20/sharpj/UClassTB.png)
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
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.
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.
QuotePoor seaboat, wet and uncomfortable, reduced performance in heavy weather
Not cool for the crew & actions...
;)
Quote from: Jefgte on February 18, 2009, 01:01:51 AM
QuotePoor 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.
I reckon that the seakeeping figure, while not great, is also not bad for her size and speed.
Did you test flushdeck hull ?
I didn't.
I have tested flush deck hull (ala Flechter)...
hmmm...
Nearly identical (0.95) for seaboat quality.
;)
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 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.)
(http://img.photobucket.com/albums/v20/sharpj/TClassTB.png)
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 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.
(http://img.photobucket.com/albums/v20/sharpj/gccl16.png)
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
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."
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 ... :)
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.
Did you test 4x120 ?
Probably a better choice for 1500t DD
I don't currently utilize 120mm, so didn't test any configurations with it.
Iberia & Peru use 120mm guns.
You could have quickly this gun.
;)
I like the 5 turret arrangement - like the famous French Contre-torpilleurs of the 20s-30 - handsome super destroyers - but crying out for guns to match...