[gurps] The Trimaran of a Webbed Mariner

[Onno Meyer]

David replied to me:
> > Oh, and I wonder if the tanker isn't more exciting than the trimaran.
> 
> Even bigger suspension of disbelief, though.

Reasonable historical galleys could carry 150-250 rowers, anything beyond
that would be a 'White Elephant'. We're not reasonable here, so take the 
high number and double it. That doesn't have to mean 500 oars, but the 
stats are the same for 100 five-man oars or 500 one-man oars. They 
generate 3,000 lbs. of motive thrust, equivalent to a 200-kW screw. 

The level of hydrodynamics is hard to decide. While Vehicles gives some 
guidelines regarding length-to-beam and roles, modern merchant hulls 
spend a lot of brain-power (and computing power) on the most efficient
shapes. So go out on a limb and call it very fine. (We talked about that 
regarding the Archvillain's Yacht, but I'm deliberately cinematic here.)

That allows a calculation of the maximum loaded weight for a given speed.

mph weight
1   23,328,000 tons
2    1,030,962 tons
3      166,277 tons
4      45,562 tons
5      16,692 tons
6       7,348 tons

Even with the best will, it is clear that the formula breaks down at low 
speed. On the other hand, our rowers might be able to move a hull
of several thousand tons at a few mph ...

Onno