A quickie today -- Friday night, still working on articles, and the world of productivity is grinding to a halt as everyone becomes unavailable for a 3-day weekend.

I have a Microship-model deadline: Sept 16. That's the day Robb Walker of Nelson/Marek will visit the lab to discuss the requirements in more detail and see what miracles I'll want him to perform. Worked on it some more this evening... made 6 stands to hold it up, and cut the main tube of the recumbent from a piece of pine. I'm getting into a major wall-staring phase as I try to integrate dozens of conflicting issues into a 10' cockpit section (now further complicated by things learned from The Cruising Multihull book).

I spoke today with Current Designs, the kayak builder in British Columbia. While he hasn't explicitly said he would donate boats (Expeditions or maybe Libra doubles), he does seem very enthusiastic about the project and told me they're entering their quiet season which lasts until about November. So the time is now to define the spec and make a proposal... he's sending literature which will help me determine the optimal placement of crossmembers and hopefully avoid any need for a custom deck plan.

One of the issues related to that is hatch design. Trimaran floats are subjected to very heavy abuse including submarining through waves, which in any kind of interesting conditions will quickly strip anything loose from a kayak deck -- including the typical fabric cockpit cover. I'll have to either redo the hatches to allow yacht-scale square hatches, or have Mark Plastics (Hesperia) fashion custom removable plexiglass covers that can then be gasketed over the curved coamings with stock hardware. The kayak main cockpits will also need automatic electric bilge pumps.

Drainage is another problem... depending on bouyancy calculations and the PPI figures (pounds of added load per inch of immersion), the heights of cockpit and sleeping cabin floors are going to have to be adjusted to allow self-bailing. If not, every time a big wave hits with open hatches it will cost a lot of work and/or power...

(I don't mean to give the impression that I'm heading offshore into blue water, but I'd rather agonize now over worst-case scenarios and then find myself well prepared than design the boat for gentle waterways and then drown on my first tentative bay crossing. Thinking always in terms of heavy wind and concomitant waves will make this a much more robust boat, though it's maddening right now.)

I'm toying with the idea of a hard top over the cockpit, with easily removable vinyl windows. While this sounds rather ugly, it will provide shade and basic weather protection in what is otherwise a rather open boat, sliding hatch covers notwithstanding. It is yet unclear whether there will be any way to "go below" in the main cockpit -- the bike imposes tough constraints (and no, I'm not fully wedded to its inclusion just yet, though it does convenienty define the inflexible parameters of the human pedaling envelope, a level of functionality upon which I stubbornly insist).

Anyway, the hard top would cover most of the 4' hull width, and to allow passage forward the non-slip walkways would move outboard to the extended wheel wells -- which could actually run most of the length of the boat, bounded by lifelines and stanchions. Sounding more like a yacht all the time. Maybe I should just find $60,000 and buy an F-27 <grin>.

Speaking of the F-27, by the way, I'm seriously considering stealing its aka-deployment scheme instead of my initial parallelogram method wherein the kayaks stay in the water and sweep sternward. It's a bit hard to explain in text, but basically the crossbeams are on wonderfully articulated arms when vertical, but settle into very strong wells when deployed, requiring only a single bolt as a hold-down. I'll show you the video if you want to see how this works (TJ saw it today).

Other design issues currently affecting my thinking are the required bouyancy of the outrigger kayaks, which should nominally support the full boat to provide an effective transverse static righting moment after being heeled to its point of maximum stability. Such considerations affect kayak volume, overall beam, and even the length-to-beam ratio or "fineness" (which should be a minimum of 8:1 on the center hull according to White, though present design at 28' x 4' is 7:1). The crossbeam should also support at least 20 times the overall boat weight to handle worst-case conditions. Given kayaks of known dimensions (18'10" LOA, 22.25" beam, and 118.6 gallon volume -- or 21'8", 30", and 184.4 gal if I elect to use doubles instead), we have to work backward to set constraints on center hull parameters, which are themselves driven in the opposite direction by liveability requirements... then tying it all together with crossbeams at a known distance apart but yet-unknown length and downward curve (which cannot be known until bouyancy calculations show the difference in freeboard between vaka and amas...). Hell, after all this, the electronics will be a SNAP.

Steve