Project Windrigger evolved out of my need for a sailing boat for cruising with my family onboard, the waters of the Barrier Reef 2500kms by road north from my home.
For this I required a safe and comfortable boat which was easy to rig and sail; simple to launch and reload for trailering behind a family-size car; affordable (costing less than $10000 to build) and fast as my Flying Dutchman.
As none of the existing trailer-sailers satisfied this requirement, I setout to design one - the result is the conceptual design shown below (Fig 5 of the proposal) and which I have named Dreamtime.
Fore and aft overhang
|Twin-sail steering||10 metre transportable cruiser with water ballast outrigger|
My reasons for the following aspects of this design are: proa configuration because of its capsize recovery potential - as shown below (and in Fig 3 of the proposal); the Tee-section hull - a logical solution for the requirements of standing and sitting headroom and narrow waterline beam for high-speed potential; the fore and aft hull-overhangs providing reserve buoyancy to minimise pitching; water ballast in the outrigger to reduce the probability of capsize, provide fresh water supply for cruising and to reduce trailering weight by dumping the water when trailering; twin sails to assist steering, provide a low centre of effort, and balanced sail area when running before the wind; sailboard-type sailrig because this rig has powered the sailboat-speed recordholders since 1976.
WINDRIGGER CAPSIZE RECOVERY CONCEPTUnlock and rotate outrigger
|Unballasted Outrigger - Fun sailer||
Ballasted Outrigger - Family Sailer|
with buoyant bridgedeck
I did not build Dreamtime because of risks due to lack of design rules on proas and radical aspects of the design. I decided to first learn about proas by a process of trial and modification using sailing prototypes - starting with Windrigger MkI.
I prepared a research and development program covering for example: comparative tests of dory, assymetrical, concave and circular hull cross-sections; hull/sail balance of reversable sailrigs; drag of outriggers and structural considerations; steering; capsize recovery; water ballast; trailering, accommodation and asthetics. Details of the prototypes and the R & D program are available on request.
Due to lack of financial support, I have not advanced beyond trialling Windrigger Mk I, but have learnt enough from two years of experimentation with it to design and build a 6.8 metre proa incorporating most of the aspects of Dreamtime. So anyone who does not have the confidence to build the big proa of their dreams, consider building Windrigger Mk I and sail it to test your ideas.