http://www.axisandallies.org/forums/index.php?topic=27876.15;wap2
The board’s Search box will give you links to various threads where this topic has been discussed. The search term SCULPT SCALE will give you some hits, but typing SCALE by itself will probably give you even more. Here’s one thread (look at Reply # 17)…
http://www.axisandallies.org/forums/index.php?topic=27876.15
…where there’s some information which I’ve copied below.
knp7765:
Hey Guys,
I’ve seen a lot of people wonder about the scale of A&A pieces so I decided to check things out. Basically, I just looked the different classes up on Wikipedia, got the length in meters and converted that to millimeters, then divided that number by the length of the sculpts. I came up with a lot of very weird numbers. Obviously these pieces are not a uniform scale.
In fact, it looks like what WOTC decided to do was to make all the pieces in each class a roughly uniform size – all carriers are 64mm long, all battleships are 58-62mm long, all cruisers are 50-56mm long, etc. I think that probably makes more sense for gaming purposes. That way each class of unit fits within a certain size limit so they will be easier to recognize by gamers. If they went by actual sizes, we would end up with some battleships being larger than carriers, some cruisers being larger than battleships and so on. In fact, the Gangut class Soviet battleship is shorter than the cruisers of all five nations in real life.
Here’s what I came up with for the US units:
USS Wasp Carrier – 1/3530
USS Iowa Battleship – 1/4433
USS Portland Cruiser – 1/3720
USS Johnston Destroyer – 1/2442
USS Ray Submarine – 1/2066
Liberty Transport Ship – 1/2990
B-17 Flying Fortress – 1/687
P-38 Lightning fighter – 1/577
M4 Sherman Tank – 1/265
