As an Ex-Sailor, I must confess that I myself used the guide to get the idea of what a catamaran looked. I will probably be referencing it again, due to the fact that I was a sailor on submarines and we didn't have to worry about all them sails and stuff
I am curious, though, if you know all the signs and flags you'll be needing for shipboard operations, and I can't wait to see you describe them.
I'm not 100% certain, and it is far to late for me to look it up right now, but there are, in the navy, flags used for when their are Diver's in the water. There are also flags and lights we look for on vessels when out at sea that denote what they are or if they're not moving, like fishing lights, I believe there are diver lights and flags they (civilians) have to use as well when out at sea.
I will try and find as many references for your perusal on the morrow. I just got done implementing the last of my changes to chapter 3 of SW and am most keen on going to sleep. Tomorrow is going to be a long day.
But, just for our sakes (and in the hopes that we really do get to see the next chapter before the week is out, like on tuesday, hint hint), here is what a diver flag looks like
And here is a brief description:
Here is the page I got that information from.
Diver's Flag and info
Here is another site with more flags and brief meanings.
My link