WesWorld

How about some real merchant ships, Ro-Pax, Contaimers & Bulkers?

I have tried my rather inexperienced hand at SS for a merchantman, and one of the problems I had was setting the freeboard. Any suggestions on how you would do that on a merchantman - profile wise they usually have a forecastle, the center island and an aftercastle as opposed a flush deck.

My friend i thing tha springsharp is not appropriate program to design a merchant ship, cause warships have other standarts than merchants!
I am not a naval architect and i know little about this section but merchant ships needs high freeboards, big draft and breadth as regards their length and in springsharp this is very bad for steadines of a vessel...but as i said before this program includes some sections as guns, armour which counterbalance to the final result....so i think is immposible to design a merchant ship in springsharp!
I have never tried to do this ....if anybody thinks that it could be done then just tell it guys!

It's very possible, actually. It's more accurate in SS3, because it allows for cargo to be stowed below the freeboard, but it still works in SS2.

Few examples in a minute.

As for the first post i eddit as:
How about some real Merchant ships drawings as Ro-Ro pax, Containerships, Bulkers and Tunkers???

Quoted

Originally posted by TexanCowboy
It's very possible, actually. It's more accurate in SS3, because it allows for cargo to be stowed below the freeboard, but it still works in SS2.

Few examples in a minute.

I'm looking forward to them

A theoretical design concept by LVB, the largest merchant marine company in Latvia. The plan was abandoned due to the lack of facilites and resources to build said ship in.

Livora, Latvia Bulk Carrier laid down 1929

Displacement:
9,230 t light; 9,444 t standard; 10,697 t normal; 11,700 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(450.00 ft / 450.00 ft) x 64.00 ft x (20.00 / 21.59 ft)
(137.16 m / 137.16 m) x 19.51 m x (6.10 / 6.58 m)

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 9,135 shp / 6,815 Kw = 17.00 kts
Range 9,000nm at 15.00 kts
Bunker at max displacement = 2,256 tons

Complement:
525 - 683

Cost:
£1.449 million / $5.797 million

Distribution of weights at normal displacement:
Armament: 0 tons, 0.0 %
Machinery: 281 tons, 2.6 %
Hull, fittings & equipment: 2,774 tons, 25.9 %
Fuel, ammunition & stores: 1,467 tons, 13.7 %
Miscellaneous weights: 6,175 tons, 57.7 %
- Hull below water: 3,500 tons
- Hull above water: 2,050 tons
- On freeboard deck: 500 tons
- Above deck: 125 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
21,261 lbs / 9,644 Kg = 196.9 x 6 " / 152 mm shells or 2.7 torpedoes
Stability (Unstable if below 1.00): 1.33
Metacentric height 4.2 ft / 1.3 m
Roll period: 13.1 seconds
Steadiness - As gun platform (Average = 50 %): 100 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has raised forecastle, raised quarterdeck ,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.650 / 0.659
Length to Beam Ratio: 7.03 : 1
'Natural speed' for length: 21.21 kts
Power going to wave formation at top speed: 39 %
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 %, 30.00 ft / 9.14 m, 24.00 ft / 7.32 m
- Forward deck: 30.00 %, 20.00 ft / 6.10 m, 23.00 ft / 7.01 m
- Aft deck: 35.00 %, 23.00 ft / 7.01 m, 20.00 ft / 6.10 m
- Quarter deck: 15.00 %, 24.00 ft / 7.32 m, 24.00 ft / 7.32 m
- Average freeboard: 22.86 ft / 6.97 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 65.7 %
- Above water (accommodation/working, high = better): 172.1 %
Waterplane Area: 22,062 Square feet or 2,050 Square metres
Displacement factor (Displacement / loading): 159 %
Structure weight / hull surface area: 80 lbs/sq ft or 388 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.92
- Longitudinal: 2.15
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, rides out heavy weather easily

Cargo: 5,050 tons of containers, dry goods, etc.
Cranes: 500 tons for cranes, boats, etc., to unload or load the ship
Upperworks: 100 tons for radio and other miscellanous goods

In SS2 one cannot make a ship with hull form You ask for.
There 7 point too put in the freeboard hight.
For what You asking one needs 10.
So no.
Not in SS2.

Or I'm missing something.

Any reason you made the Livora so ahistorically massive?

Umm......because the Russkie's built them this large, too, and just for demonstration purposes?

It doesn't really exist, just wrote a little backstory about it for presentation purposes.

I'll post stuff soon!

I tried using springsharp to design one cargo ship of the 30s!
I think BruceDuncan had wright it can be done....just check this out!



SS SOFIA BRITTANIA, Greece Cargo laid down 1930

Displacement:
5.947 t light; 6.073 t standard; 6.299 t normal; 6.479 t full load

Dimensions: Length overall / water x beam x draught
397,85 ft / 393,70 ft x 55,77 ft x 24,61 ft (normal load)
121,26 m / 120,00 m x 17,00 m x 7,50 m

Machinery:
Coal fired boilers, simple reciprocating steam engines,
Direct drive, 1 shaft, 1.957 ihp / 1.460 Kw = 12,00 kts
Range 6.000nm at 7,00 kts
Bunker at max displacement = 406 tons (100% coal)

Complement:
30

Cost:
£1,031 million / $4,123 million

Distribution of weights at normal displacement:
Armament: 0 tons, 0,0%
Machinery: 274 tons, 4,3%
Hull, fittings & equipment: 5.473 tons, 86,9%
Fuel, ammunition & stores: 351 tons, 5,6%
Miscellaneous weights: 200 tons, 3,2%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
36.361 lbs / 16.493 Kg = 336,7 x 6 " / 152 mm shells or 9,5 torpedoes
Stability (Unstable if below 1.00): 1,06
Metacentric height 2,3 ft / 0,7 m
Roll period: 15,4 seconds
Steadiness - As gun platform (Average = 50 %): 72 %
- Recoil effect (Restricted arc if above 1.00): 0,00
Seaboat quality (Average = 1.00): 2,00

Hull form characteristics:
Hull has raised forecastle
Block coefficient: 0,408
Length to Beam Ratio: 7,06 : 1
'Natural speed' for length: 19,84 kts
Power going to wave formation at top speed: 20 %
Trim (Max stability = 0, Max steadiness = 100): 36
Bow angle (Positive = bow angles forward): 8,00 degrees
Stern overhang: -6,56 ft / -2,00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29,53 ft / 9,00 m
- Forecastle (10%): 28,87 ft / 8,80 m (20,67 ft / 6,30 m aft of break)
- Mid (50%): 19,69 ft / 6,00 m
- Quarterdeck (8%): 20,67 ft / 6,30 m
- Stern: 21,33 ft / 6,50 m
- Average freeboard: 21,14 ft / 6,44 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 19,4%
- Above water (accommodation/working, high = better): 140,0%
Waterplane Area: 12.855 Square feet or 1.194 Square metres
Displacement factor (Displacement / loading): 843%
Structure weight / hull surface area: 214 lbs/sq ft or 1.046 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 2,56
- Longitudinal: 11,27
- Overall: 2,97
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, rides out heavy weather easily


The only thing i change was the crew number from 300++ to 30 cause a cargo ship of her era this number was the usual!
Another thing that i disagree is the max shell hits to be destroyed ...300+++ and 8 torpedos....its a lot for such ships....According history 1-2 torpedos were enough as well as less than 30 hits by gunfire!!!

Quoted

Originally posted by Navarchos
Another thing that i disagree is the max shell hits to be destroyed ...300+++ and 8 torpedos....its a lot for such ships....According history 1-2 torpedos were enough as well as less than 30 hits by gunfire!!!

This is because Springsharp presumes military-style bulkhead spacing.

Add in the miscellanous weight to account for cargo, and it will quickly plummet.

Springstyle notes indicate that for merchant ships, you have to divide crew and damage values by 10.

Quoted

Transports and merchant ships: The "miscellaneous
weight" feature of the program allows weight to be reserved
for cargo capacity. So to give a ship a cargo capacity of
10,000 tons, simply provide that much miscellaneous weight.

Provide at least one gun, if only a .30 caliber or
9 mm (0.9 cm) weapon. Otherwise Spring Style will list
"0 x 0.0" guns, which looks silly! (*)

However, note that cargo ship capacity is normally
listed in gross registered tons (GRT), which is a measure of
volume, not weight - 100 cubic feet of enclosed volume =
1 gross registered ton. (However, registered tonnage is
usually about the same magnitude as weight capacity.)

To determine gross registered tonnage, make the
following calculations:

1) Multiply "loading submergence" (listed below the weights
table in the ship report) times ship's freeboard (listed
under hull strength in the hull characteristics section.)

2) Add the result to normal displacement.

3) Multiply by 35, then divide the answer by 100.
This is the gross registered tonnage for a typical
cargo ship.

Also, for civilian merchant ships, divide crew and
damage survival values by 10 - they have small crews, and
lack the extensive compartmentation of naval ships. For
naval transports, divide crew by 5 but leave survival
values unchanged. Adjust your ship report accordingly;
I compute and list Gross Registered Tonnage on the line
below displacement.

(*) only necessary for Springstyle.

Interesting, I don't ever recall seeing that section for calculating GRT before.

Quoted

Originally posted by Brockpaine
Interesting, I don't ever recall seeing that section for calculating GRT before.

It's only rough. Most historical ships were <5000GRT for the period.

SpringSharp is actually written as a tool for supporting design of weight-constrained ships, not just warships. I don't know if IanRG knows this, but that's what it does. As such, it is perfectly capable of designing battleships and the like, and does a tolerable job on cruisers - that's what it was originally written for. Coal and ore carriers are more or less the same sort of problem - actually, if for some peculiar reason there was a need for new battleships, designers of ore carriers would be the best ones to give the job.

Anyhow. Because SpringSharp is designed for weight-constrained ships, it doesn't have the ability to model volume well. This is why it doesn't handle aircraft carriers well, and why you can get away with some ridiculous ships with obscene amounts of artillery. This is also why modelling cargo ships and passenger liners is difficult - they're volume constrained ships.

There are workarounds, of course, but a tool for doing this kind of work would be fundamentally different.

Quoted

Interesting, I don't ever recall seeing that section for calculating GRT before.

Further to what RA said, it's basically a fudge which (presumably) gives more-or-less correct numbers for the ships Rick Robinson (who wrote the original SpringStyle) calibrated it against. The old (pre-1975) gross tonnage rules are hideously complex, with all sorts of convoluted exemptions, but fortunately the current rules are rather simpler, and I know those were written to give more or less the same answer as for the old rules. Even then, there's the added complication that net tonnage is also a rather important figure, and still quite complicated to calculate. For one, you need the cargo volume to work with, which depends on all sorts of things...

This is why naval architects go spare when someone quotes a 'tonnage' for a ship and doesn't specify what it is - there are at least five different figures which could be used, all of which mean different things.

Trying my hand at simming a small freighter using a historical precedent.

The ship looks like this:



My initial sim comes out like this:

C-1 Rev A, TBD River-Sea Freighter laid down 1940

Displacement: 4,988 t light; 5,094 t standard; 5,300 t normal; 5,465 t full load

Dimensions: Length overall / water x beam x draught
301.97 ft / 282.15 ft x 44.95 ft x 19.52 ft (normal load)
92.04 m / 86.00 m x 13.70 m x 5.95 m

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Ends: Unarmoured
- Torpedo Bulkhead:
9.84" / 250 mm 196.85 ft / 60.00 m 22.97 ft / 7.00 m

Machinery:
Diesel Internal combustion motors,
Geared drive, 1 shaft, 1,353 shp / 1,009 Kw = 11.00 kts
Range 6,000nm at 10.00 kts
Bunker at max displacement = 371 tons

Complement: 31-43

Cost: £1.078 million / $4.311 million

Distribution of weights at normal displacement:

Armament: 0 tons, 0.0 %
Armour: 1,646 tons, 31.1 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 1,646 tons, 31.1 %
- Armament: 0 tons, 0.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 36 tons, 0.7 %
Hull, fittings & equipment: 2,505 tons, 47.3 %
Fuel, ammunition & stores: 312 tons, 5.9 %
Miscellaneous weights: 800 tons, 15.1 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 2,607 lbs / 1,182 Kg = 24.1 x 6 " / 152 mm shells or 1.2 torpedoes
Stability (Unstable if below 1.00): 1.02
Metacentric height 1.6 ft / 0.5 m
Roll period: 15.1 seconds
Steadiness - As gun platform (Average = 50 %): 100 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:

Hull has raised forecastle
Block coefficient: 0.749
Length to Beam Ratio: 6.28 : 1
'Natural speed' for length: 16.80 kts
Power going to wave formation at top speed: 33 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 40.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 23.62 ft / 7.20 m
- Forecastle (20 %): 20.34 ft / 6.20 m (13.12 ft / 4.00 m aft of break)
- Mid (50 %): 21.33 ft / 6.50 m
- Quarterdeck (15 %): 13.12 ft / 4.00 m
- Stern: 21.33 ft / 6.50 m
- Average freeboard: 18.11 ft / 5.52 m

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 36.7 %
- Above water (accommodation/working, high = better): 112.7 %
Waterplane Area: 10,615 Square feet or 986 Square metres
Displacement factor (Displacement / loading): 210 %
Structure weight / hull surface area: 134 lbs/sq ft or 655 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.98
- Longitudinal: 8.65
- Overall: 2.29
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, rides out heavy weather easily

Low-stowed cargo simmed as torpedo bulkhead
High-stowed cargo simmed as miscellaneous weight
Rev A - Total cargo - 1646+800 = 2446 vice Historical Deadweight 3900dwt
Final crew size and damage values divided by 10 for civilian ships

I probably have the freeboard figures and distribution wrong to match the historical drawing. I don't seem to be able to match the historical dimensions for the overall length or deadweight.

Any suggestions for improvement will be most welcome.

And this is what I know of the historical vessel that served as design inspiration

m/s TEJA exMAGYAR TENGERÉSZ exSIMFEROPOL
Ship classification: MAGYAR VITÉZ class, single screw sea-going freighter

Technical details:

Built: 1942, Ganz & Co. Electrical-, Machine-Waggon & Shipyard Co. Ltd., Budapest/Újpest, HU, #1464

Length overall: 94,00 m
Lenght between perpendiculars: 86,00 m
Extrem breadth: 13,70 m
Depth: 6,90 m
Draft: 5,95 m
Displacement: 5300 t

DWT 3900

Main engine type: Ganz-Jendrassik VIII. JhR. 216
Power: 4 X 400 Hp
Velocity: 11

What's with the massively thick torpedo bulkhead? I doubt the original had that.....