ORIGINAL: m10bob
I might be off base here, but just commenting.
I have never liked the use of a percentage% of this or that to represent a ships' carrying capacity, especially when some modders have admitted they are doing so to either "balance" the game, or slow it down.
<snip>
Not off base at all. Conceptually agree that every ship should have her specs, but there were too many types, and a vast amount of variation between types. For my scenarios, I use about 15-18 AK types for each of the US, Allied and Japanese, divided into older (1920s) and newer types, the types ranging from 8500 to 1200 metric, subdivided by speed, and further subdivided by range. It gives a useful mix and allows for custom tailoring of national merchant fleets according to their published proportions of vessels.
For example, a standard C2-Cargo comes in 23 different flavors; shelter deck, scantling deck, reefer, no reefer, wet tanks, no wet tanks, diesel, turbine, hold arrangement, deck fittings, and all of these differed for each of 5 major shipping companies. A standard vessel would be different were it ordered by Lykes, Moore McCormack or Luckenback, say.
Brits & the other Euros were even more varied. They didn’t take lines off a standard design, but rather designed and built a series of sisters (2, 3, 4, maybe 5) off a customer spec. Shippers ordered ships for anticipated service runs. A ship built for So. American service would be different from a ship built for No. American service, African service, or the India/Asia run.
What I do is group things, like the C1-A, or C2-Cargo, and find the mean, sigma, of the capacity distribution from the design files. That becomes the capacity of a C2-Cargo (for example). I use sigma to differentiate means between C2-Cargo, C2-F/T/S, C2-S-B1, C2-S-AJ, for instance, so I can get a nice range of ships with different capacities, ranges, etc.. But the capacity number chosen is not a soft percentage. It is a statistical average of actuals, in metric tons.
For Euros & Japanese the data is a bit more spotty, so I use certain fitting parameters. Once again, find the means of the actuals, but then also group the data source vessels with respect to the box rule and midship section (preferably prismatics, where available) and define a working range of classes. Vessels having a paucity of data are fit within a category based on their coefficients. Once again, the capacity number is not a percentage, but reflects rather an actual value of a chosen representative vessel.
Similarly for tankers. A T2 can’t really carry 141k bbls of crude, but it can carry 141k bbls of a mixed cargo of avgas, iso-octane, and napthalene; but you don’t get many of those. Fortunately, the game runs in tons, and the tonnage limits are available. For a SE-A1, it’s about 13,880 metric. That allows all cargos to be somewhat fungible, irrespective of density. Tankers are also grouped with respect to the box rule and midship section (they fit very well) and, once again, indeterminate vessels are fit within a category based on their coefficients.
Tying it all together. All the values used are from design draughts and builder’s verifications of vessels floating on their lines; using design values allows consistency and uniformity across the board without resort to soft assumptions. Everyone will, therefore, find a favorite vessel with different IRL numbers, and they are, necessarily, more correct. I just thought it wise to show why I do it how I do it, and why my Fort Flatulence nominally carrys less (or more) than the IRL Pigsnout Park.
