Byzantine Empire 1923-1924...

[Jefgte]

I have never SS a 40t MTB at 34kts.
I guess the seakeeping must be a disaster.

;D

[The Rock Doctor]

They make decent submarines.

[Desertfox]

Yeah SS can't do planning hulls and alot of its Seakeeping metrics are tied to hull length, so you can easily make a battlecruiser do 34kts, but anything under 300ft is a huge pain.

[TacCovert4]

I have never SS a 40t MTB at 34kts.
I guess the seakeeping must be a disaster.

;D

Yeah planing hulls are a totally different animal.  Their seakeeping improves as they speed up. 

[Kaiser Kirk]

Folks are correct that SS "seakeeping" is a rough guide.
It seems better understood relative to the class.

For practical considerations, we use SS as our guide, so if you're triggering a warning the ship doesn't work,
that is a potential problem.  For the Roman ships, they were  unseaworthy with low freeboard....then came a hurricane.

The Friedman book on Destroyers I got talks about how the nominal DD speed and the practical were so
vastly different. Far more so than our trial speeds.

For wargaming purposes, SeeKrieg weather includes a seastate chart with wave heights.


Conceptually, I am thinking there must be a way to compare these wave heights vs. the average freeboard- or forecastle freeboard
would be a limiting factor - and then use the 'poor"  "good " or "excellent" as modifiers increasing
that effective number to show the seastate limit before the ship has to slow down.
Making a practical system, and one that isn't too much workload to implement,
that is still the problem. 

Right now the evaluation is a little more Ad Hoc.
Aka MTBs are restricted to calm seas. torpedoes have problems in big seas, and
I peer at the ship's seakeeping, but we haven't had a battle during a major storm...everyone waits for MTB weather.
So it would be something I'd look at just in a storm encounter where it could matter.
thus replicating the Duke of York & DDs vs Schnhorst limitations,
where the two big ships could maintain higher speeds.

[Jefgte]

Certainly a better ship & build in 50m shipyards...

T280, Byzantine Empire 50m Shipyards laid down 1924

Displacement:
   280 t light; 288 t standard; 306 t normal; 320 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (163,19 ft / 160,76 ft) x 17,06 ft x (10,01 / 10,31 ft)
   (49,74 m / 49,00 m) x 5,20 m  x (3,05 / 3,14 m)

Armament:
      1 - 3,00" / 76,2 mm 45,0 cal gun - 13,62lbs / 6,18kg shells, 150 per gun
     Quick firing gun in deck mount, 1924 Model
     1 x Single mount on centreline, forward deck forward
      1 - 1,85" / 47,0 mm 45,0 cal gun - 3,20lbs / 1,45kg shells, 200 per gun
     Quick firing gun in deck mount, 1924 Model
     1 x Single mount on centreline, aft deck aft
      2 - 0,30" / 7,6 mm 90,0 cal guns - 0,02lbs / 0,01kg shells, 2 000 per gun
     Machine guns in deck mounts, 1924 Model
     2 x Single mounts on sides, forward deck centre
      Weight of broadside 17 lbs / 8 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,39" / 10 mm         -               -
   2nd:   0,39" / 10 mm         -               -
   3rd:   0,24" / 6 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 9 800 shp / 7 311 Kw = 27,61 kts
   Range 2 500nm at 10,00 kts
   Bunker at max displacement = 33 tons

Complement:
   36 - 47

Cost:
   £0,102 million / $0,407 million

Distribution of weights at normal displacement:
   Armament: 3 tons, 1,1 %
      - Guns: 3 tons, 1,1 %
   Armour: 3 tons, 1,0 %
      - Armament: 3 tons, 1,0 %
   Machinery: 159 tons, 51,9 %
   Hull, fittings & equipment: 87 tons, 28,3 %
   Fuel, ammunition & stores: 26 tons, 8,5 %
   Miscellaneous weights: 28 tons, 9,2 %
      - Hull below water: 10 tons
      - Hull above water: 2 tons
      - On freeboard deck: 16 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     73 lbs / 33 Kg = 5,4 x 3,0 " / 76 mm shells or 0,1 torpedoes
   Stability (Unstable if below 1.00): 1,06
   Metacentric height 0,4 ft / 0,1 m
   Roll period: 11,4 seconds
   Steadiness   - As gun platform (Average = 50 %): 48 %
         - Recoil effect (Restricted arc if above 1.00): 0,12
   Seaboat quality  (Average = 1.00): 0,76

Hull form characteristics:
   Hull has raised forecastle,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0,390 / 0,397
   Length to Beam Ratio: 9,42 : 1
   'Natural speed' for length: 12,68 kts
   Power going to wave formation at top speed: 75 %
   Trim (Max stability = 0, Max steadiness = 100): 61
   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:   25,00 %,  13,78 ft / 4,20 m,  12,47 ft / 3,80 m
      - Forward deck:   25,00 %,  7,87 ft / 2,40 m,  7,87 ft / 2,40 m
      - Aft deck:   25,00 %,  7,87 ft / 2,40 m,  7,87 ft / 2,40 m
      - Quarter deck:   25,00 %,  7,87 ft / 2,40 m,  7,87 ft / 2,40 m
      - Average freeboard:      9,15 ft / 2,79 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 174,9 %
      - Above water (accommodation/working, high = better): 69,5 %
   Waterplane Area: 1 677 Square feet or 156 Square metres
   Displacement factor (Displacement / loading): 45 %
   Structure weight / hull surface area: 20 lbs/sq ft or 95 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 5,75
      - Overall: 0,63
   Cramped machinery, storage, compartmentation space
   Cramped accommodation and workspace room
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather


16t for 2 x 2TT x 533 HW
2T for climatisation
10t lest

Trial speed: 32kts
Bonus: 4,39

[Jefgte]

The final project
50m-300t, made to work in Red Sea.

T300 - 50m Shipyards, Byzantine Empire Mocha class laid down 1924

Displacement:
   300 t light; 309 t standard; 332 t normal; 351 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (163,38 ft / 160,76 ft) x 17,29 ft x (10,73 / 11,11 ft)
   (49,80 m / 49,00 m) x 5,27 m  x (3,27 / 3,39 m)

Armament:
      1 - 3,00" / 76,2 mm 45,0 cal gun - 12,50lbs / 5,67kg shells, 180 per gun
     Quick firing gun in deck mount, 1924 Model
     1 x Single mount on centreline, forward deck forward
      2 - 1,85" / 47,0 mm 50,0 cal guns - 3,00lbs / 1,36kg shells, 270 per gun
     Quick firing guns in deck mounts, 1924 Model
     2 x Single mounts on sides, aft deck centre
      1 - 1,85" / 47,0 mm 50,0 cal gun - 3,00lbs / 1,36kg shells, 300 per gun
     Quick firing gun in deck mount, 1924 Model
     1 x Single mount on centreline, aft deck aft
      2 - 0,30" / 7,6 mm 90,0 cal guns - 0,02lbs / 0,01kg shells, 2 000 per gun
     Machine guns in deck mounts, 1924 Model
     2 x Single mounts on sides, forward deck forward
      2 raised mounts
      Weight of broadside 22 lbs / 10 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,39" / 10 mm         -               -
   2nd:   0,39" / 10 mm         -               -
   3rd:   0,39" / 10 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 10 000 shp / 7 460 Kw = 27,37 kts
   Range 3 000nm at 10,00 kts
   Bunker at max displacement = 41 tons

Complement:
   38 - 50

Cost:
   £0,110 million / $0,440 million

Distribution of weights at normal displacement:
   Armament: 5 tons, 1,6 %
      - Guns: 5 tons, 1,6 %
   Armour: 4 tons, 1,1 %
      - Armament: 4 tons, 1,1 %
   Machinery: 170 tons, 51,0 %
   Hull, fittings & equipment: 91 tons, 27,3 %
   Fuel, ammunition & stores: 32 tons, 9,7 %
   Miscellaneous weights: 31 tons, 9,3 %
      - Hull below water: 12 tons
      - Hull above water: 1 tons
      - On freeboard deck: 18 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     80 lbs / 36 Kg = 5,9 x 3,0 " / 76 mm shells or 0,1 torpedoes
   Stability (Unstable if below 1.00): 1,06
   Metacentric height 0,4 ft / 0,1 m
   Roll period: 11,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0,15
   Seaboat quality  (Average = 1.00): 0,81

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0,390 / 0,398
   Length to Beam Ratio: 9,30 : 1
   'Natural speed' for length: 12,68 kts
   Power going to wave formation at top speed: 75 %
   Trim (Max stability = 0, Max steadiness = 100): 61
   Bow angle (Positive = bow angles forward): 11,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   25,00 %,  13,45 ft / 4,10 m,  11,84 ft / 3,61 m
      - Forward deck:   12,50 %,  11,84 ft / 3,61 m,  7,91 ft / 2,41 m
      - Aft deck:   47,50 %,  7,91 ft / 2,41 m,  7,91 ft / 2,41 m
      - Quarter deck:   15,00 %,  7,91 ft / 2,41 m,  7,91 ft / 2,41 m
      - Average freeboard:      9,30 ft / 2,83 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 173,4 %
      - Above water (accommodation/working, high = better): 70,5 %
   Waterplane Area: 1 699 Square feet or 158 Square metres
   Displacement factor (Displacement / loading): 47 %
   Structure weight / hull surface area: 20 lbs/sq ft or 98 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 6,04
      - Overall: 0,64
   Cramped machinery, storage, compartmentation space
   Cramped accommodation and workspace room
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

18t for 2 x 3TT x 533
1T for climatisation
12t lest

Trial / Attack speed: 31,5kts
Bonus: 4,13

[TacCovert4]

I like it.  It's specialized,  but that's not a bad thing at all.  Heavy torpedo load, fire control,  ability to fire off of bearing,  it's got what you want in a large torpedo boat. 

[Jefgte]

I prefer this kind of torpedo boat for the Red Sea. It will behave better than 40t MTBs that are too sensitive to rough seas.

;)

[TacCovert4]

I prefer this kind of torpedo boat for the Red Sea. It will behave better than 40t MTBs that are too sensitive to rough seas.

;)

I'm transitioning away from MTBs.  The fact that I can build these, that don't suffer from comm issues and can launch torpedoes at  ranges where they're not going to get massacred by gunfire just make 500t GTBs more useful. 

[Jefgte]

BB1 & BB2 class with 8x254/22kts are little BBs for colonial jobs.
I studying a 1924 rebuilt for BB4 class.
21 to 24kts Useful in the far east colonial jobs... most Japanese meduim BBs are 21/24kts.
-----

BB4	19250t => 19150t		$x2	BP
	19150x 0,25		4,787	1,925
	new guns	8x191	0,888	0,444	(444t)
	new guns	12x120	0,288	0,144	(144t)
	new guns	4x76,2	0,048	0,024	(24t)
	new deck	240t	0,24	0,24	(+10mm)
	new engines	1647t	3,294	1,647
	Equipment	7345t	1,469	1,469
	misW-Fuel	904t	0,904	0,904
		Total =>	11,918	6,797
Scrapp 15%	old guns	8x191	0,069	0,069	(465t)
	old guns	8x102	0,007	0,007	(46t)
	old armour	0	0	0
- scrap cost	old engines	2427t	0,364	0,364
- scrap cost		Total =>	0,44	0,44
	11,918 - 0,44   =>		11,478$
	6,797 - 0,44  =>			6,357 BP
			$	BP

BB4, Byzantine Empire BB4 laid down 1905 (Engine 1924)

Displacement:
   19 150 t light; 20 427 t standard; 21 644 t normal; 22 617 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (573,82 ft / 573,82 ft) x 83,99 ft x (25,11 / 26,05 ft)
   (174,90 m / 174,90 m) x 25,60 m  x (7,65 / 7,94 m)

Armament:
      8 - 13,50" / 343 mm 40,0 cal guns - 1 409,00lbs / 639,11kg shells, 100 per gun
     Breech loading guns in turret on barbette mounts, 1905 Model
     4 x Twin mounts on centreline, evenly spread
      8 - 7,50" / 191 mm 45,0 cal guns - 200,00lbs / 90,72kg shells, 150 per gun
     Breech loading guns in casemate mounts, 1905 Model
     8 x Single mounts on sides, evenly spread
      12 - 4,72" / 120 mm 45,0 cal guns - 50,00lbs / 22,68kg shells, 200 per gun
     Quick firing guns in casemate mounts, 1905 Model
     12 x Single mounts on sides, evenly spread
      12 raised mounts
      8 - 3,00" / 76,2 mm 45,0 cal guns - 13,62lbs / 6,18kg shells, 300 per gun
     Anti-air guns in deck mounts, 1924 Model
     8 x Single mounts on side ends, evenly spread
      8 raised mounts
      4 - 0,30" / 7,6 mm 90,0 cal guns - 0,02lbs / 0,01kg shells, 4 000 per gun
     Machine guns in deck mounts, 1905 Model
     4 x Single mounts on side ends, evenly spread
      4 raised mounts
      Weight of broadside 13 581 lbs / 6 160 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   12,6" / 320 mm   374,02 ft / 114,00 m   12,01 ft / 3,66 m
   Ends:   4,72" / 120 mm   196,85 ft / 60,00 m   9,84 ft / 3,00 m
     2,95 ft / 0,90 m Unarmoured ends
   Upper:   5,51" / 140 mm   374,02 ft / 114,00 m   8,01 ft / 2,44 m
     Main Belt covers 100 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   13,4" / 340 mm   5,91" / 150 mm      12,6" / 320 mm
   2nd:   5,91" / 150 mm   3,94" / 100 mm      4,72" / 120 mm
   3rd:   0,98" / 25 mm         -         0,98" / 25 mm
   4th:   0,39" / 10 mm         -               -
   5th:   0,39" / 10 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 3,35" / 85 mm
   Forecastle: 1,97" / 50 mm  Quarter deck: 1,97" / 50 mm

   - Conning towers: Forward 11,81" / 300 mm, Aft 5,91" / 150 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 50 000 shp / 37 300 Kw = 24,19 kts
   Range 8 900nm at 12,00 kts
   Bunker at max displacement = 2 190 tons

Complement:
   891 - 1 159

Cost:
   £1,799 million / $7,195 million

Distribution of weights at normal displacement:
   Armament: 1 822 tons, 8,4 %
      - Guns: 1 822 tons, 8,4 %
   Armour: 7 737 tons, 35,7 %
      - Belts: 3 502 tons, 16,2 %
      - Armament: 1 898 tons, 8,8 %
      - Armour Deck: 2 040 tons, 9,4 %
      - Conning Towers: 296 tons, 1,4 %
   Machinery: 1 647 tons, 7,6 %
   Hull, fittings & equipment: 7 345 tons, 33,9 %
   Fuel, ammunition & stores: 2 494 tons, 11,5 %
   Miscellaneous weights: 600 tons, 2,8 %
      - Hull below water: 100 tons
      - Hull above water: 100 tons
      - On freeboard deck: 200 tons
      - Above deck: 200 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     32 344 lbs / 14 671 Kg = 26,3 x 13,5 " / 343 mm shells or 3,7 torpedoes
   Stability (Unstable if below 1.00): 1,19
   Metacentric height 5,3 ft / 1,6 m
   Roll period: 15,3 seconds
   Steadiness   - As gun platform (Average = 50 %): 58 %
         - Recoil effect (Restricted arc if above 1.00): 0,71
   Seaboat quality  (Average = 1.00): 1,16

Hull form characteristics:
   Hull has raised forecastle,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0,626 / 0,630
   Length to Beam Ratio: 6,83 : 1
   'Natural speed' for length: 23,95 kts
   Power going to wave formation at top speed: 51 %
   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 (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20,00 %,  24,80 ft / 7,56 m,  21,19 ft / 6,46 m
      - Forward deck:   30,00 %,  17,91 ft / 5,46 m,  16,14 ft / 4,92 m
      - Aft deck:   30,00 %,  16,14 ft / 4,92 m,  16,14 ft / 4,92 m
      - Quarter deck:   20,00 %,  16,14 ft / 4,92 m,  16,14 ft / 4,92 m
      - Average freeboard:      17,71 ft / 5,40 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 65,2 %
      - Above water (accommodation/working, high = better): 128,0 %
   Waterplane Area: 36 112 Square feet or 3 355 Square metres
   Displacement factor (Displacement / loading): 107 %
   Structure weight / hull surface area: 163 lbs/sq ft or 797 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,96
      - Longitudinal: 1,46
      - Overall: 1,00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Misc Weight 600t:
182t fire control-1918
25t for Marconi
100t for extra pump installation
100t for climatization
100t for Admiral staff or reserved
93t reserved

[The Rock Doctor]

You gotta watch out for those Japanese battleships.

All these rebuilds - yours, Kirk's, etc - are interesting to look at.  I guess I didn't really build the right kind of battleships for such a program.

[Jefgte]

You gotta watch out for those Japanese battleships...

The Japanese have smaller BBs than the Parthians and Byzantines, but they are more numerous and faster.

[TacCovert4]

Meanwhile, Aztec BBs........We exist!

[Jefgte]

Meanwhile, Aztec BBs........We exist!

The Aztecs are enemies...unlikely

;)