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A reprint of an article by Frank Bethwaite, first published in 1995.

From time to time this subject has been raised in a peripheral manner such as the problems of a "two very light lady crew", and some encouragement has been given to find local answers. I now make the point that the subject is becoming central to the Tasars growth through Asia.

It is now ten years since the first Tasars went to Japan. In the years since we have watched with admiration while Japanese Tasar sailors grew into a coherent fleet, began to visit World Championships in Australia and Canada and England and invited us to enjoy their own Worlds and their hospitality at Hayama.

We have watched while their sailors, and particularly their better sailors, have developed speed and racing skills which I suggest are now about as good as ours. I have become increasingly concerned to note that while they can now often finish well in light and moderate wind conditions, they never finish well in stronger winds.

I now realize that with the present weight rule they can never expect to finish well in stronger winds and therefore can never expect to win any regatta.

My reason for bringing this subject up now is that in addition to the present Japanese concern voiced by Keiji Yoshikawa, others will shortly become concerned. Last year we shipped 9 B-14s to Hong Kong, and one B-14 to Brunei. At least one Tasar demonstrator has been requested in the next container to Hong Kong. South East Asia is the world's fastest growing market for Western-style recreational activities such as sailing. I think it is important that we be seen to be conscious of this problem, and to be willing to trial possible solutions. as a matter of some urgency.

I was responsible for the crew-weight rule. To start the discussion, it may be helpful if I outline why we needed a rule, and how it has worked for us, and why I now think we need to refine it.

In 1960 a group of us observed that while there were good boats for children, and good boats for athletic males - the Olympic classes and the Australian skiff classes - there were no boats truly suitable for a man and a woman. We decided to develop one ourselves, and set ourselves the object of "Most fun and highest performance within the strength of a man and a woman to handle in the water and out". We put on the water prototypes which had stiff conventional masts and full sails, men and women enjoyed them and sailed competitively, the women who were central within the class used their skills to make the class a pleasant community to be in, and a great class began to grow. At the same time a core group within the class engaged in the wind-tunnel, tow-test and empirical experimentation which is described in my book, and the boats became more efficient, more adjustable, more pleasant to sail, and faster. in 1969 1 put a well-developed wingmast rig on a particularly intelligently designed hull, and we had a break-through boat which was much faster than anything which preceded it.

But it was soon found that while a crew, (usually man and woman) of about 300 to 320lbs total weight had sailed faster than any other crew in the previous boats, a crew of about 250lbs sailed 10 to 12 minutes faster in the new boats when the wind was 8 knots or more. i.e. when they could plane on a reach. The effect on the class was shattering. Within a year the number of women sailing had reduced by nearly half. They had been driven away or had walked away from the boats rather than sail 10 minutes slower than boats crewed by lighter children.

My response was to redesign the rig and increase the sail area to re-match the unchanged weight of a man and a woman with the new rig technology. This boat became the Nova. Those of us who were the nucleus of this new "retain women" class developed its rules, and central within these was the crew weight rule. We invited the remaining man-woman NS crews to re-rig their hulls and sail with us. Within a few years the Nova had been consumerized to become the Tasar.

The object of the crew weight rule which I wrote in 1972 was to ensure that women normal (Western) stature would never again be put at any disadvantage. In this it has succeeded brilliantly, and this function of the rule must never be changed. But at that time we simply did not pause to consider whether or not it might be fair to any lighter crew.

Now, in changed circumstances 23 years later, I think we should take a harder look at what might both protect the place of Western-stature women in Tasar crews and also be fair to all crews of smaller stature whom we invite to sail with us.

At the end of this note I tabulate what I think would be the effect of some possible changes to the rules. My beliefs were illuminated by two initial experiences, and subsequent observation has suggested that these were true, so I will share them here.

Planing and non-planing conditions in flat water. 
Mark, my elder son, designed and built the bull on which I put the new rig in 1969, and he won the 1969 Australian Championships with it. Julian and I won the 1970 NSW State champs in a similar boat with one 2nd and five lsts in a 100-boat fleet. By 1971 the influx of kids and the outflow of women threatened the class, so I decided to measure the problem. The 1972 Australian NSI4 Championships were sailed on the Hume Weir, near Albury. The typical summer wind pattern there is a morning cold-air  downhill flow of 15 knots about dawn fading to nothing at noon, and light winds from anywhere after that. So morning and afternoon races tended to be in distinctly different winds. The lake near the dam is about two miles wide from shore to shore, so the water is "inland lake" caIrn, i.e. it is glassy in light airs. I estimated the weights of all 70-odd crews and timed all the boats around all the marks and across the finish line and noted the winds as the races progressed, and analyzed the results.

The key observation is that in races in which the wind speed was 0 to 7 knots and no boats planed, the average elapsed time of the first 5 "light" (i.e. about 250lb) crews was one minute faster than the average time of the first 5 "heavy" (i.e. about 300lb) crews.

But in races in which the wind speed was 8 knots or more, the light crews planed sooner, the planing speed brought the apparent wind forward of the beam on the reaching legs and they then "rode their own apparent wind" and they finished on average 12 minutes faster than the heavy crews.

Non-planing conditions in waves. 
At the 1983 Tasar World Championships at Vancouver, many races were sailed in winds, typical of English Bay, of 4 to 6 knots. But these conditions were not at all the same as at Albury. English Bay is 4 miles North-south and 10 miles east-west and is open to the Georgian channel and carries much commercial traffic, so the water surface has the constant small waves typical of Sydney Harbor, Port Phillip, Annapolis or say Plymouth in similar light winds.

One crew sailed the first few races lighter than 300 lbs. At this reduced weight they sailed off down wind with unmatchable speed, and won those races by legs. They sailed subsequent races at 300 lbs, and such races as they won, they won by lengths, not legs.

Everything that I have seen in subsequent years has confirmed these lessons, i.e., that when sailing similar hulls and for crews of equal skill:

1. In non-planing winds and flat water, crew-weight makes little difference.
2. In non-planing conditions and even small waves. lighter crews sail faster.
3. In planing conditions, lighter crews sail faster.
(4. In very strong winds heavy crews will retain control better and may sail faster, but only in winds stronger than we are expected to race in.)

I have tabulated below what I think happens now, what 1 think would happen if we carried no ballast, and what I think would happen if we carried only some fraction of the ballast we now require to be carried.

Rule Scenario
Estimated performance of 2501b crew compared with 300lb crew.

1. Present rule: Carry total difference between crew weight and 300 lb as ballast

Wind	Upwind	X'wind	D'wind
Light	E	E	E
Mod	S	E	E
Strong	SS	S	E

  A light crew can never win a regatta

2. Carry No Ballast

Wind	Upwind	X'wind	D'wind
Light	F	F	F
Mod	E	FF	FF
Strong	S	F	FF

A light crew will win every regatta (as with NS 14's at Albury)

3. Carry as ballast say 67% of difference between crew weight and 300 lb.

Wind	Upwind	X'wind	D'wind
Light	E	E	EF
Mod	ES	E	EF
Strong	S	ES	EF

E = equal, EF = Slightly Faster, FF = Much Faster, ES = Slightly Slower, SS = Much Slower.

At some percentage all crews will have an equal chance of winning the average regatta.

It would be the business of several years of trialling different percentages to establish confidence in the final figure chosen. The tricky point is that the only trialling which would be meaningful would be at World Cbampionships etc where the best Asian and Western crews compete, so an interim rule to permit this trialling with systematically changed percentages would be necsssary.

I invite the views of owners, world-wide, on this question of performance equalization for Tasar crews of different weights.

Frank Bethwaite

Note. The conclusions above apply only to planing sailboats which sail slower than the wind, such as Tasars and 470's.

Non-planing keelboats all heel when close-hauled and reaching, and the less they heel the faster they sail, so these boats, from Ocean Racers to Etchells, all sail faster to windward in all winds, and no slower downwind in any winds, with heavy crews, so heavy crews always win.

Skiffs which sail faster than the wind, such as the Eighteens, also B-l4's etc., obey different laws - they sail close-reaching even when sailing downwind so need real "power" to drive themselves up to the optimum apparent wind speed for that true wind speed. The end result is that the heaviest crews do not sail fastest to windward in the stronger 'winds, neither do the lightest crews sail fastest downwind in the lighter winds.

Performance equalization for crews of different weights is turning out to be a complicated business.

posted 2001/09/30

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