New Destroyers for Rohan in 1912

Started by Ithekro, April 14, 2008, 12:20:01 PM

Previous topic - Next topic

Ithekro

A small class of heavier destroyers using the latest engine and other technologies is being designed to be laid down later in 1912.  These vessels are named after some of the ancient Éothéod from which the Rohirrim originated.

Éomund
Forthwini
Fram
Frumgar
Léod
Marhwini


Rohan Destroyer laid down 1912

Displacement:
   1,000 t light; 1,042 t standard; 1,187 t normal; 1,298 t full load

Dimensions: Length overall / water x beam x draught
   300.00 ft / 300.00 ft x 32.00 ft x 8.00 ft (normal load)
   91.44 m / 91.44 m x 9.75 m  x 2.44 m

Armament:
      3 - 4.50" / 114 mm guns in single mounts, 45.56lbs / 20.67kg shells, 1912 Model
     Quick firing guns in deck mounts
     on centreline, evenly spread
     Aft Main mounts separated by engine room
      4 - 1.50" / 38.1 mm guns in single mounts, 1.69lbs / 0.77kg shells, 1912 Model
     Quick firing guns in deck mounts
     on side, evenly spread
      4 - 0.45" / 11.4 mm guns in single mounts, 0.05lbs / 0.02kg shells, 1912 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 144 lbs / 65 kg
   Shells per gun, main battery: 225
   6 - 18.0" / 457.2 mm above water torpedoes

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.00" / 25 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 1 shaft, 20,000 shp / 14,920 Kw = 28.49 kts
   Range 2,500nm at 15.00 kts (Bunkerage = 260 tons)

Complement:
   100 - 131

Cost:
   £0.131 million / $0.525 million

Distribution of weights at normal displacement:
   Armament: 18 tons, 1.5 %
   Armour: 7 tons, 0.6 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 7 tons, 0.6 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 579 tons, 48.8 %
   Hull, fittings & equipment: 336 tons, 28.3 %
   Fuel, ammunition & stores: 187 tons, 15.8 %
   Miscellaneous weights: 60 tons, 5.1 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     415 lbs / 188 Kg = 9.1 x 4.5 " / 114 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.33
   Metacentric height 1.5 ft / 0.5 m
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.16
   Seaboat quality  (Average = 1.00): 1.07

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.541
   Length to Beam Ratio: 9.38 : 1
   'Natural speed' for length: 17.32 kts
   Power going to wave formation at top speed: 67 %
   Trim (Max stability = 0, Max steadiness = 100): 65
   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:      18.00 ft / 5.49 m
      - Forecastle (20 %):   14.00 ft / 4.27 m
      - Mid (50 %):      14.00 ft / 4.27 m
      - Quarterdeck (15 %):   14.00 ft / 4.27 m
      - Stern:      14.00 ft / 4.27 m
      - Average freeboard:   14.32 ft / 4.36 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 175.2 %
      - Above water (accommodation/working, high = better): 121.1 %
   Waterplane Area: 6,643 Square feet or 617 Square metres
   Displacement factor (Displacement / loading): 66 %
   Structure weight / hull surface area: 27 lbs/sq ft or 134 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.91
      - Overall: 0.57
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform

P3D

2500@15kts range is short for a big DD IMO.
The first purpose of a warship is to remain afloat. Anon.
Below 40 degrees, there is no law. Below 50 degrees, there is no God. sailor's maxim on weather in the Southern seas

The Rock Doctor

I'm not sure - if intended as a fleet escort, it might be short-legged, but if intended as a local strike unit, it may be fine.

I find the speed low-ish, though.  Not much advantage over new cruisers.

Ithekro

They are basically faster versions of the previous model with triple torpedo mounts rather than twins.  I may have over estimated her extra weight, but the range was the best I could do without too much fiddling.  They are about 2.5 knots faster than the previous two models of destroyer and have 500 nm greater range at 15 knots.  Plus a few more lighter quick fires.

Korpen

#4
Quote from: Ithekro on April 14, 2008, 12:20:01 PM
A small class of heavier destroyers using the latest engine and other technologies is being designed to be laid down later in 1912.  These vessels are named after some of the ancient Éothéod from which the Rohirrim originated.
While she carries a nice payload of 60 tons, i find her a bit short in most other respects. As P3D said, her range is a bit on the low side, at least for anything other the point defence (As Rocky pointed out).
I am somewhat baffled by were the weight have gone, as she is not all that fast, about as fast as most 750ton DDs, and with no more firepower or range. Granted she is more spacious.
So while not a bad boat per se, I think she is sub-optimal for her weight.

EDIT: They also have a quite high block coefficient for a destroyer.
Card-carrying member of the Battlecruiser Fan Club.

P3D

Quote from: Korpen on April 14, 2008, 12:46:06 PM
While she carries a nice payload of 60 tons, i find her a bit short in most other respects. As P3D said, her range is a bit on the low side, at least for anything other the point defence (As Rocky pointed out).
I am somewhat baffled by were the weight have gone, as she is not all that fast, about as fast as most 750ton DDs, and with no more firepower or range. Granted she is more spacious.
So while not a bad boat per se, I think she is sub-optimal for her weight.

EDIT: They also have a quite high block coefficient for a destroyer.
High BC is the cause for being overweight for the capacity. Making the ship longer and deeper would help. Also, the relatively short ship require high freeboard to get any decent seakeeping rating.
The first purpose of a warship is to remain afloat. Anon.
Below 40 degrees, there is no law. Below 50 degrees, there is no God. sailor's maxim on weather in the Southern seas

Ithekro

Most Rohirrim destroyers are sub-optimal.  They tend to be more gun platform than torpedo boat and they tend to be slower than average.  Most Rohirrim operations don't envision the destroyers as escorts outside of home waters (actually Rohan doesn't envision many operations outside of home waters...the whole non-expansionistic mindset), leaving the long ranged escorting to the cuisers for now.  This may change, or Rohan may return to building more smaller cruisers again instead of destroyers for escorts.

Korpen

Quote from: Ithekro on April 14, 2008, 12:56:39 PM
Most Rohirrim destroyers are sub-optimal.  They tend to be more gun platform than torpedo boat and they tend to be slower than average.  Most Rohirrim operations don't envision the destroyers as escorts outside of home waters (actually Rohan doesn't envision many operations outside of home waters...the whole non-expansionistic mindset), leaving the long ranged escorting to the cuisers for now.  This may change, or Rohan may return to building more smaller cruisers again instead of destroyers for escorts.
The same goes for the dutch boats, and they are faster, longer ranged and more heavily armed.
2500nm@15 is around 400nm at full speed, is that considered enogh?
Card-carrying member of the Battlecruiser Fan Club.

P3D

WWI destroyers with similar range requirement (i.e. operate near bases) had longer ranges for similar size - especially if they were oil fired. KUK, RN, HSF, MN, pick any. Not a big increase is needed, 3000@15 would be OK.
The first purpose of a warship is to remain afloat. Anon.
Below 40 degrees, there is no law. Below 50 degrees, there is no God. sailor's maxim on weather in the Southern seas

Sachmle

While not as spacious nor as comfortable, but if you're not going very far comfort is a luxury.  1.51 kt faster, with a heavier broadside, and 2 more TT.

NUS, Export Destroyer laid down 1912

Displacement:
   1,000 t light; 1,041 t standard; 1,209 t normal; 1,343 t full load

Dimensions: Length overall / water x beam x draught
   320.00 ft / 317.00 ft x 30.00 ft x 9.00 ft (normal load)
   97.54 m / 96.62 m x 9.14 m  x 2.74 m

Armament:
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1912 Model
     Quick firing guns in deck mounts
     on centreline ends, evenly spread
      2 - 4.00" / 102 mm guns in single mounts, 32.00lbs / 14.51kg shells, 1912 Model
     Quick firing guns in deck mounts
     on side, all amidships
      6 - 1.00" / 25.4 mm guns in single mounts, 0.50lbs / 0.23kg shells, 1912 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 131 lbs / 59 kg
   Shells per gun, main battery: 200
   8 - 18.0" / 457.2 mm above water torpedoes

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.00" / 25 mm         -               -
   2nd:   1.00" / 25 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 23,105 shp / 17,236 Kw = 30.00 kts
   Range 2,982nm at 15.00 kts
   Bunker at max displacement = 302 tons

Complement:
   102 - 133

Cost:
   £0.136 million / $0.543 million

Distribution of weights at normal displacement:
   Armament: 16 tons, 1.4 %
   Armour: 9 tons, 0.7 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 9 tons, 0.7 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 621 tons, 51.4 %
   Hull, fittings & equipment: 304 tons, 25.1 %
   Fuel, ammunition & stores: 209 tons, 17.3 %
   Miscellaneous weights: 50 tons, 4.1 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     336 lbs / 152 Kg = 10.5 x 4.0 " / 102 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.40
   Metacentric height 1.5 ft / 0.4 m
   Roll period: 10.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.15
   Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.494
   Length to Beam Ratio: 10.57 : 1
   'Natural speed' for length: 17.80 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 67
   Bow angle (Positive = bow angles forward): -10.00 degrees
   Stern overhang: 3.00 ft / 0.91 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19.00 ft / 5.79 m
      - Forecastle (20 %):   16.00 ft / 4.88 m
      - Mid (50 %):      16.00 ft / 4.88 m (9.00 ft / 2.74 m aft of break)
      - Quarterdeck (15 %):   9.00 ft / 2.74 m
      - Stern:      9.00 ft / 2.74 m
      - Average freeboard:   12.74 ft / 3.88 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 181.3 %
      - Above water (accommodation/working, high = better): 82.7 %
   Waterplane Area: 6,304 Square feet or 586 Square metres
   Displacement factor (Displacement / loading): 59 %
   Structure weight / hull surface area: 26 lbs/sq ft or 127 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.35
      - Overall: 0.55
   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

"All treaties between great states cease to be binding when they come in conflict with the struggle for existence."
Otto von Bismarck

"Give me a woman who loves beer and I will conquer the world."
Kaiser Wilhelm

"If stupidity were painfull I would be deaf from all the screaming." Sam A. Grim

Korpen

Quote from: Sachmle on April 14, 2008, 02:27:29 PM
While not as spacious nor as comfortable, but if you're not going very far comfort is a luxury.  1.51 kt faster, with a heavier broadside, and 2 more TT.
Oh, posting design suggestion! :)

From De Schelde:
Better speed, range and firepower.
QuoteH-Class (E), Rohan? Hunter laid down 1912

Displacement:
   1 000 t light; 1 047 t standard; 1 275 t normal; 1 457 t full load

Dimensions: Length overall / water x beam x draught
   329,64 ft / 324,80 ft x 29,53 ft x 11,20 ft (normal load)
   100,47 m / 99,00 m x 9,00 m  x 3,42 m

Armament:
      5 - 4,49" / 114 mm guns in single mounts, 45,20lbs / 20,50kg shells, 1912 Model
     Breech loading guns in deck mounts
     on centreline ends, majority aft, 3 raised mounts - superfiring
      2 - 0,31" / 8,0 mm guns in single mounts, 0,02lbs / 0,01kg shells, 1912 Model
     Machine guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 226 lbs / 103 kg
   Shells per gun, main battery: 170
   4 - 17,7" / 450 mm above water torpedoes

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,39" / 10 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 22 313 shp / 16 646 Kw = 30,00 kts
   Range 4 000nm at 15,00 kts
   Bunker at max displacement = 410 tons

Complement:
   106 - 138

Cost:
   £0,146 million / $0,585 million

Distribution of weights at normal displacement:
   Armament: 28 tons, 2,2 %
   Armour: 5 tons, 0,4 %
      - Belts: 0 tons, 0,0 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 5 tons, 0,4 %
      - Armour Deck: 0 tons, 0,0 %
      - Conning Tower: 0 tons, 0,0 %
   Machinery: 624 tons, 49,0 %
   Hull, fittings & equipment: 302 tons, 23,7 %
   Fuel, ammunition & stores: 275 tons, 21,6 %
   Miscellaneous weights: 41 tons, 3,2 %
      - Fire control 25 tons
      - Torpedoes 6 tons
      - Radio 10 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     321 lbs / 145 Kg = 7,1 x 4,5 " / 114 mm shells or 0,2 torpedoes
   Stability (Unstable if below 1.00): 1,45
   Metacentric height 1,5 ft / 0,5 m
   Roll period: 10,0 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0,26
   Seaboat quality  (Average = 1.00): 1,03

Hull form characteristics:
   Hull has rise forward of midbreak, low quarterdeck
   Block coefficient: 0,415
   Length to Beam Ratio: 11,00 : 1
   'Natural speed' for length: 18,02 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 68
   Bow angle (Positive = bow angles forward): 15,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18,04 ft / 5,50 m
      - Forecastle (12 %):   17,06 ft / 5,20 m
      - Mid (30 %):      17,06 ft / 5,20 m (9,19 ft / 2,80 m aft of break)
      - Quarterdeck (10 %):   8,53 ft / 2,60 m (9,19 ft / 2,80 m before break)
      - Stern:      8,53 ft / 2,60 m
      - Average freeboard:   11,53 ft / 3,51 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 178,7 %
      - Above water (accommodation/working, high = better): 93,7 %
   Waterplane Area: 5 960 Square feet or 554 Square metres
   Displacement factor (Displacement / loading): 62 %
   Structure weight / hull surface area: 27 lbs/sq ft or 133 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 1,15
      - Overall: 0,54
   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
Card-carrying member of the Battlecruiser Fan Club.

Borys

Ahoj!
Very nice design, Sachmle!
Although ... there is not enough deck space to fit all that :)
Borys
NEDS - Not Enough Deck Space for all those guns and torpedos;
Bambi must DIE!

Sachmle

#12
I had to give you something to complain about Borys.  ;D

Too narrow? Or just not long enough?
"All treaties between great states cease to be binding when they come in conflict with the struggle for existence."
Otto von Bismarck

"Give me a woman who loves beer and I will conquer the world."
Kaiser Wilhelm

"If stupidity were painfull I would be deaf from all the screaming." Sam A. Grim

Ithekro

#13
What of this?  A fourth main gun, slightly more speed for the power, and much greater range?  Still only two triple torpedo mounts.  Also Rohan values survivability to some extent.  The first design could take 9 shells of its own size, while the Dutch vessel (if using the 4.5" guns of Rohan) would survive less (since it is scaled on a 4" shell)  The South American design can only survive 7 shells while this design can survive 8 (two full broadsides from its own class).

Éomund

Rohan Destroyer laid down 1912

Displacement:
   1,000 t light; 1,049 t standard; 1,265 t normal; 1,432 t full load

Dimensions: Length overall / water x beam x draught
   310.00 ft / 310.00 ft x 32.00 ft x 10.00 ft (normal load)
   94.49 m / 94.49 m x 9.75 m  x 3.05 m

Armament:
      4 - 4.50" / 114 mm guns in single mounts, 45.56lbs / 20.67kg shells, 1912 Model
     Quick firing guns in deck mounts
     on centreline, evenly spread
     Aft Main mounts separated by engine room
      4 - 1.50" / 38.1 mm guns in single mounts, 1.69lbs / 0.77kg shells, 1912 Model
     Quick firing guns in deck mounts
     on side, evenly spread
      4 - 0.45" / 11.4 mm guns in single mounts, 0.05lbs / 0.02kg shells, 1912 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 189 lbs / 86 kg
   Shells per gun, main battery: 225
   6 - 18.0" / 457.2 mm above water torpedoes

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.00" / 25 mm         -               -
   2nd:   0.50" / 13 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 1 shaft, 20,000 shp / 14,920 Kw = 28.82 kts
   Range 3,775nm at 15.00 kts (Bunkerage = 388 tons)

Complement:
   105 - 137

Cost:
   £0.139 million / $0.555 million

Distribution of weights at normal displacement:
   Armament: 24 tons, 1.9 %
   Armour: 11 tons, 0.9 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 11 tons, 0.9 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 599 tons, 47.4 %
   Hull, fittings & equipment: 306 tons, 24.2 %
   Fuel, ammunition & stores: 265 tons, 21.0 %
   Miscellaneous weights: 60 tons, 4.7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     377 lbs / 171 Kg = 8.3 x 4.5 " / 114 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.44
   Metacentric height 1.7 ft / 0.5 m
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.17
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.446
   Length to Beam Ratio: 9.69 : 1
   'Natural speed' for length: 17.61 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 69
   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:      16.00 ft / 4.88 m
      - Forecastle (20 %):   12.00 ft / 3.66 m
      - Mid (50 %):      12.00 ft / 3.66 m
      - Quarterdeck (15 %):   12.00 ft / 3.66 m
      - Stern:      12.00 ft / 3.66 m
      - Average freeboard:   12.32 ft / 3.76 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 173.1 %
      - Above water (accommodation/working, high = better): 95.3 %
   Waterplane Area: 6,309 Square feet or 586 Square metres
   Displacement factor (Displacement / loading): 68 %
   Structure weight / hull surface area: 28 lbs/sq ft or 135 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.20
      - Overall: 0.55
   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


P3D

Why insisting on 20,000SHP engines. Not really adequate for 1000t IMO.
What about making the design smaller instead - start at 750t and increase weight until acceptable?
The first purpose of a warship is to remain afloat. Anon.
Below 40 degrees, there is no law. Below 50 degrees, there is no God. sailor's maxim on weather in the Southern seas