The Tiki Rig Article (intro)
by James Wharram
May 2000
One aspect of our designs that web viewers seem fascinated with is what we call our TIKI ‘Soft Wing Sail Rig’ (other people are increasingly calling it ‘The Wharram Wing Sail Rig’).
Several years ago, I wrote and published worldwide, an article on the origin of this rig; why and how we developed it. For this web page contribution I propose to re-publish the article in full with this foreword.
In any given month, somewhere in the world, some yacht magazine, will be publishing an article on ‘Sail Efficiency’, on ‘How to get the Best out of your Sails’. 99% of them will be referring to the Bermudan Sail Rig. The ‘Efficiency’, the ‘Best’ that they are writing about, is to sail 1-2 º closer to the wind!! These articles are not about ‘Cost Efficiency’; they are not about all-round weather ‘Handling Efficiency’; they are not about boat ‘Safety Efficiency’. They are about ‘Race Winning Efficiency’. Simply put, if you are racing around a buoy 60 miles away to windward, the boat that can sail 1º closer to the wind, sailing at, let us say, 6 knots, will at the end of 10 hours be 1 sea mile closer to the buoy. It may be able to sail around the buoy without tacking. A boat that sails 1º less well to windward at 6 knots may have to put a tack in to get around that buoy. One mile at 6 knots equals 10 minutes of time. If the buoy is 30 miles away, then the 1º less efficient to windward boat has lost 5 minutes in the race to get around the buoy. If it is 15 miles away, it has lost 2 ½ minutes in trying to get around the buoy. If it is 7 miles away, one will lose 1-¼ minutes to get around the buoy.
When you realize that in racing 'winning is All', you can understand that to a racing yachtsman 1º less efficiency in windward sailing is a very serious matter. The racing yachtsman to be the ‘Winner’, with Kevlar sails, Moulded sails, Multiple cut sails, heavy winches etc., is prepared to spend enormous sums of money to get an extra 1º (or even less) ‘Efficiency’. He will, in heavy, powerful winds overstress his hull. He is prepared to sail at uncomfortable and dangerous angles of heel (or in multihulls with dinghy style stability). He will expect his crew to ‘sit out’ on the weather rail in rain and spray to balance up the high mast.
Gladiator sailing/racing, i.e. "I am The Best", can be fun but it is a world apart from commercial or aesthetic sailing for joy!
For at least ten thousand years, man has had sailing ships. During this time, his need to sail to windward, rather than row or paddle, has been a constant necessity. For windward work he has developed the 4 sided profile sail like the Square Sail, Lug and Gaff Sail or the 3 sided profile sail like the Lateen and Crab Claw, and some four-sided sails that are a mixture of Lateen and Lug Sail profiles. For sail material, man has used leather (Roman), wool (Viking), matting (Pacific craft including junks), flax, cotton and since 1960, synthetic fibres.
The great advance in windward sailing ability in 10,000 years has been in the use of synthetic sailcloth because of its smooth finish, resistance to stretch and mould. So much of what is classed as ‘Designer Ability’ in modern windward sailing boats has, in fact, been achieved by chemists.
During the 10,000 years of windward development, sailing craft were (like the modern multihull) not self-righting. So, the sailing profiles developed were for maximum windward ability with the lowest capsizing moment. ‘Capsizing’ in discussion of multihulls is the ‘Obscene’ not to be mentioned ‘C’ word. Forgive me, therefore, if I point out that the Bermudan High Aspect Ratio rig is, sail area for sail area, the most capsizing rig in the history of sailing man! As a multihull ‘designer’ my lifelong struggle has been how to avoid the Bermudan High Aspect Sloop and still get windward ability.
20 years ago, after working for many years with traditional low aspect rigs (often as ketch or schooner) using Junk sails, Spritsails and large roach fully-battened low aspect Bermudan sails, I came up with an even more successful solution, now proven over hundreds of boats sailing in all weather conditions. The following article shows how in 1980-81 I incorporated aerodynamic theory, a traditional windward sail profile and practical common sense to produce the ‘TIKI or Wharram Soft Wing-Sail Rig’.
