"It's the horrible black beast of..."
aaarrrrrghhh run away.
Thanks for that point on the l:b ratio, although I am not too worried about people being unable to sit side by side; that might be true for the average Italian man that you are controlling, but the Japanese are usually not that big. :-)
I never tried to sim something this small before without a negative misc. load (did create a 1x1x1x0.5 thing with a lot of negative misc. load and a speed of +70 knots with springstyle).
What is the misc. weight for? is it a torpedo or some depth charges?
Well, if I had a torpedo on board, I guess I would have entered that into SS. No, I entered the miscellaneous weight to allow for additional people to get (squeezed) into the boat. Unlike the troop transports where you use 2 tons per soldier, I go here for the weight per person. The 2 tons allow for 25 men/women with an average weight of 81.2kg or 12 angry sumo wrestlers with an average weight of 169.3kg (or any other combination).
Hooman, I was wondering if you ever tried to put an inch of armor on a boat of such size. The only things you can add without too much problem are CT, shields, and Torpedo Bulkhead. That or you just add something like 1 millimeter of armor (like those shields on the Aquila)
As to the wasting of hull strength you mentioned, I think you might be referring to the 1400 NM range. I agree, but when I was messing around with the design, I used that to get both stability and seakeeping above 1. Looking at the second and third attempt, the armor does pretty much the same.
Attempts 2 and 3 (thankfully with a more normal range). Since attempt 2 was bigger, I adjusted the miscellaneous weight on the main design so 4 of the 2nd design boats could still be carried.
At this moment I am thinking of using two 10 ton boats and four 5 ton boats (that is, if I can fit them somewhere on the ship).
I decided to divide the damage survival values by 10 as one normally would do with a civilian vessel, something I did not do with the first design.
Any ideas? Suggestions?
Perhaps I should allow for 4 horses and riders with gear with the 2.5 ton miscellaneous weight...
... but then, I would have to put additional miscellaneous weight on the HIJMS Kameko-chan as well (not only for additional boats which I can hardly put anywhere, but for the horses, stables, hay etc. as well).
Attempt 2:
Boat for the light cruiser HIJMS Kameko-chan (10 ton version), Japan Motorboat laid down 1921
Displacement:
10 t light; 10 t standard; 10 t normal; 10 t full load
Loading submergence 10 tons/feet
Dimensions:
49.21 ft x 9.84 ft x 1.21 ft (normal load)
15.00 m x 3.00 m x 0.37 m
Armament:
2 - 0.30" / 7.62 mm guns
Weight of broadside 0 lbs / 0 kg
Armour:
Belt 0.59" / 15 mm, ends unarmoured
Belts cover 80 % of normal area
Main belt does not protect magazines and engineering spaces
Conning tower 0.79" / 20 mm
Machinery:
Diesel Internal combustion motors,
Direct drive, 1 shaft, 9 shp / 7 Kw = 7.00 kts
Range 400nm at 7.00 kts
Complement:
2 - 3
Cost:
£0.001 million / $0.004 million
Distribution of weights at normal displacement:
Armament: 0 tons, 0.0 %
Armour: 3 tons, 26.2 %
Belts: 3 tons, 25.4 %, Armament: 0 tons, 0.0 %, Armour Deck: 0 tons, 0.0 %
Conning Tower: 0 tons, 0.8 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 0 tons, 3.1 %
Hull, fittings & equipment: 4 tons, 41.8 %
Fuel, ammunition & stores: 0 tons, 4.1 %
Miscellaneous weights: 2.5 tons, 24.8 %
Metacentric height 0.3
Remarks:
Hull space for machinery, storage & compartmentation is excellent
Room for accommodation & workspaces is cramped
Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.35
Shellfire needed to sink: 4.9 lbs / 2.2 Kg = 362.22 x 0.3 " / 7.62 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0.04
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 54 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.00
Relative quality as seaboat: 1.08
Hull form characteristics:
Block coefficient: 0.600
Sharpness coefficient: 0.46
Hull speed coefficient 'M': 6.95
'Natural speed' for length: 7.02 kts
Power going to wave formation at top speed: 43 %
Trim: 50
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)
Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 38.8 %
Relative accommodation and working space: 75.2 %
(Average = 100%)
Displacement factor: 174 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0.98
(Structure weight / hull surface area: 10 lbs / square foot or 48 Kg / square metre)
Relative longitudinal hull strength: 1.81
(for 2.30 ft / 0.70 m average freeboard, freeboard adjustment -1.51 ft)
Relative composite hull strength: 1.04
Attempt 3:
Boat for the light cruiser HIJMS Kameko-chan (5 ton version), Japan Motorboat laid down 1921
Displacement:
4 t light; 4 t standard; 4 t normal; 5 t full load
Loading submergence 4 tons/feet
Dimensions:
32.81 ft x 6.56 ft x 1.21 ft (normal load)
10.00 m x 2.00 m x 0.37 m
Armament:
2 - 0.30" / 7.62 mm guns
Weight of broadside 0 lbs / 0 kg
Armour:
Belt 0.39" / 10 mm, ends unarmoured
Belts cover 80 % of normal area
Main belt does not protect magazines and engineering spaces
Conning tower 0.79" / 20 mm
Machinery:
Diesel Internal combustion motors,
Direct drive, 1 shaft, 6 shp / 5 Kw = 7.00 kts
Range 400nm at 7.00 kts
Complement:
1 - 2
Cost:
£0.000 million / $0.002 million
Distribution of weights at normal displacement:
Armament: 0 tons, 0.1 %
Armour: 1 tons, 21.7 %
Belts: 1 tons, 20.7 %, Armament: 0 tons, 0.0 %, Armour Deck: 0 tons, 0.0 %
Conning Tower: 0 tons, 1.0 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 0 tons, 4.7 %
Hull, fittings & equipment: 2 tons, 35.0 %
Fuel, ammunition & stores: 0 tons, 5.0 %
Miscellaneous weights: 1.5 tons, 33.5 %
Metacentric height 0.1
Remarks:
Hull space for machinery, storage & compartmentation is excellent
Room for accommodation & workspaces is cramped
Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.11
Shellfire needed to sink: 1.4 lbs / 0.6 Kg = 102.0 x 0.3 " / 7.62 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0.02
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 51 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.00
Relative quality as seaboat: 1.01
Hull form characteristics:
Block coefficient: 0.600
Sharpness coefficient: 0.46
Hull speed coefficient 'M': 6.07
'Natural speed' for length: 5.73 kts
Power going to wave formation at top speed: 57 %
Trim: 50
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)
Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 53.2 %
Relative accommodation and working space: 63.1 %
(Average = 100%)
Displacement factor: 153 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0.88
(Structure weight / hull surface area: 7 lbs / square foot or 35 Kg / square metre)
Relative longitudinal hull strength: 3.15
(for 2.17 ft / 0.66 m average freeboard, freeboard adjustment -1.07 ft)
Relative composite hull strength: 1.00
Walter
Quoted
aaarrrrrghhh run away.
Thursday, October 3rd 2024, 6:35pm
Go to the top of the page
