G'day,

Correct about the rudders. Not ideal, and could be corrected by
mounting them on a sleeve on the beam, as per Robert's suggestion.
trade off is telescoping width, or overall width. Mast head is
16.2m/53' off the water. Low for a 12m race multi, cloud scraping for
a sub one ton boat.

regards,

Rob

On Sat, May 31, 2008 at 9:50 PM, Gardner Pomper <gardner@...> wrote:
> I had a couple questions. Were you going for engineless, or are you planning
> on mounting an outboard somewhere?
>
> Also, it looks like you can't retract the rudders and still steer, so I was
> wondering what the draft is.
>
> Just for curiosity, what is the masthead height above the water?
>
> Thanks,
> - Gardner
>
>
> On Sat, May 31, 2008 at 8:32 AM, Raps callion
> <captian_rapscallion@...> wrote:
>>
>> I love the trailerable design. It exceeds my expectations in almost every
>> respect.
>> The part I love the most is the building cost and the bruce number.
>>
>> I would love to see another design with 6' headroom, trailerable, a bruce
>> number
>> this high, and at this price.
>>
>>
>>
>> ----- Original Message ----
>> From: Mike Crawford <jmichael@...>
>> To: harryproa@...
>> Sent: Friday, May 30, 2008 8:56:53 PM
>> Subject: [harryproa] Re: Trailer proa
>>
>> Rob,
>>
>> The trailerable proa looks wonderful. I was skeptical at first, but now
>> that you've upgraded the renderings, I can see that the boat really does
>> have some character of its own.
>>
>> That's also a great mast stepping solution. Some tri's require a
>> trailer to step/unstep, and that's not very useful if you're moored or at a
>> dock. Others have a-frames or gin poles, which help, but which also create
>> some serious stresses on the mast base. They are also more suited for a
>> rotating mast that fits onto a ball than for an unstayed rig that needs to
>> be lowered several feet into a hull. This is probably the simplest and most
>> stress-free solution I've seen.
>>
>> The number of trailerable boats with this level of performance and
>> accommodations can be counted on one hand, with a few fingers to spare.
>>
>> Nice job.
>>
>> - Mike
>>
>>
>> Rob Denney wrote:
>>
>> G'day,
>>
>> Trailer proa renderings are in the Files section under Maxi Trailer sailor
>>
>> 'The ultimate trailer sailor/racer cruiser' is the requirement for
>> this boat. As fast as possible, with standing headroom, minimal
>> galley, double bunk and a toilet. Trailering is mostly for the 5
>> mile trip from home to ramp, but occasionally further afield.
>>
>> Windward hull is 7m.24', leeward hull 12m/40'
>>
>> The boat is 6m/20' wide in sailing trim, but telescopes to 3.7/12'4"
>> wide for marinas and 2m/6'8" wide on the trailer. This is easily done
>> with composite beams. The mast and boom travel in cradles on the lw
>> hull deck, the beams under the cockpit. The trampoline is in two
>> pieces split fore and aft. Each piece has a 25mm dia carbon or alloy
>> tube sitting in hooks on the hull and the beams. In the middle is a
>> thicker tube for each piece. When telescoping for marina use, the
>> lee hull tramp is lifted out of it's hooks and as the hulls slide
>> together it slides over the windward tramp, so you can still walk
>> across to the other hull. For light air races, it can also be sailed
>> like this. For trailering, the tramps and the telescoped beams are
>> quickly and easily removed and stored under the the cockpit.
>>
>> The mast is telescoped to 9.2m for stepping/unstepping . A 5m long
>> pole, with a 4;1 blocjk and tackle on one end is inserted into a hole
>> in the deck next to the mast. The heel sits in a cup next to the mast
>> step. The blocks are tied around the mast at it's centre of gravity
>> approx 3.7m from the base and it is lifted up until the heel is above
>> the deck, then guided into the top bearing and lowered into place.
>> Unstepping is the opposite. Very quick and very safe.
>>
>> The reefing drawing shows sail areas incl mast of of 47 sqm/505 sq',
>> 35 sqm/376 sq' and 22 sq m/236 sq m. Storm sail is 2 sq m/22.5 sq' of
>> mast. Lots of sail up high for the light stuff, no drag or weight up
>> high for the heavy.
>>
>> Weight in sailing trim is 420 kgs and the payload 330 kgs/726 lbs.
>> Overload could be as much again without it affecting anything but the
>> speed.
>>
>> Construction method for the hulls is partially glassed panels joined
>> and compounded, with flat panels for the rest.
>>
>> Bruce number empty is 2.34. With normal payload, 1.9. Hull flying
>> wind speed 10 knots, lower with the crew sitting to leeward.
>>
>> Inside the ww hull is a double bunk at one end and the galley and
>> toilet at the other. The galley space is large, but not all of it is
>> accessible. It will probably end up being accessed through a deck
>> hatch and used for storing fenders, etc.
>>
>> The cockpit is sheltered with a folding pram hood which will ensure dry
>> sailing.
>>
>> The rudders could not be mounted on the telescoping beams, so are in
>> daggercases in the hull. Rather than use long tiller extensions,
>> there is a short athwartships tiller (magenta in the renderings) with
>> an extension (green) attached to the tiller and a car on a track on
>> the deck. The car is pulled fore and aft by lines running to
>> whipstaffs (vertical tillers, red) on the leeward end of the cockpits.
>> The lines are cleated on the whipstaffs so can be released and easily
>> replaced and retightened when the rudders are lifted and lowered.
>> This is a far easier system than wheel steering where the lines must
>> be released off the quadrants to raise the rudders.
>>
>> Comments, suggestions, criticisms welcome.
>>
>
>