Designer's Report to Tasar World Council Meeting, Phuket, July
2007
Summary
The Tasar class is emerging as a well managed, well supported,
affordable class with a boat which lies at about the highest
performance level that can be handled by the great majority of
present sailors.
This realization has important consequences for future class
promotion, class growth and class longevity.
Logic
The idea of a "class" in which all boats should be built to the
same plan and so sail at equal speed seems to date from the "Patiki
class" 18 ft Youth Trainer designed by Arch Logan for the Parnell
Yacht Club in Auckland, NZ in 1898. From this start "Class racing"
has been adopted almost universally world-wide.
The desire to eliminate real or perceived small differences
between nominally identical boats lead to the concept of "Producer-
control One Design" with Ian Bruce's Laser in 1969.
The Tasar, developed from the NS14 and Nova classes between 1972
and 1975 in cooperation with Ian Bruce followed the same
thinking.
At that point both constructors and sailors breathed a huge sigh
of relief with the belief that "That's it. These boats are truly
identical. In the future we will not change anything, ever."
But the management of a one-design class jointly by the class'
officers and the designer over a long period of time is turning out
to be a more complex exercise than originally imagined, because,
over longer periods of time, different sorts of differences begin
to appear.
• Some of these affect speed. In the case of uncored "fiberglass"
boats the skin softens with use and time and as it softens the boat
sails more slowly. The only cure for this is repeated upgrading to
a new hull.
• Some affect price and availability. In the case of the Tasar the
progressive increase in cost of Dacron sailcloth and reduction in
cost of Mylar has been responded to and handled by the class and
the designer in a copy-book manner.
o At some time in the future the progressive increase in the cost
and availability of alloy and the reduction in the cost of carbon
will probably call for a similar decision to change to carbon spars
at half the weight. The Tasar's alloy rig is the industry benchmark
for aerodynamic efficiency. To see what a carbon rig might look
like I have experimented with likely mast profiles which would
offer the same mix of mechanical and aerodynamic efficiency.
• Some affect design. Over the past four decades the average
weight of particularly the American and the Australian adolescent
and adult has increased significantly. In the case of designs which
are very weight sensitive and in which only sailors of a particular
weight can win this factor is profoundly adverse. In the case of
the Tasar the hull shape is fortunately relatively weight-tolerant,
and I used the recent opportunity of Mylar sail re-design to
increase the sail area from 123 square feet to 128 sq ft, so the
Tasar is well positioned to remain an attractive choice for the fit
but slightly heavier adult of the future.
The object of this note is to draw the class' attention to three
further factors, one only recently identified, which are likely in
the future to enable the Tasar class to grow more strongly than
might otherwise be imagined.
The first is that the Tasat class is well managed. The class is
coherent with good communication and the class' management is
strong and adaptable. Nothing could better exemplify this than
these championships which were organized with unusual speed at
relatively short notice and represent brilliant thinking "outside
the square".
The second is that the class is strongly supported and promoted by
its constructors and their agents and dealers. New Tasars of high
quality together with spare parts are quickly available globally at
affordable prices. A significant statistic is that the ISAF
recently invited constructors to display, at Hyeres, such boats as
they wished to be considered for a proposed new fast Women's
two-hander Olympic dinghy class. We put up the 29erXX. Whatever its
technical properties may be, a key statistic is that the price of
the 29erXX is about half that of any of the other 4 contenders. The
Tasar is similarly built and priced. My point is that most of the
other classes which ten or twenty years ago attracted similar
sailors have not survived nearly as well, so a flow of sailors from
declining classes into this more vital and affordable class is
likely.
The third factor is new. For the last three/four years I have been
working with the sailing simulator to find out what best can be
taught on the simulator, and how best to teach it. Access to the
simulator has been like having a microscope where previously the
view was through frosted glass. The key lesson has been the
realization that the great majority of sailors - I would say 90% to
95% - sail with a handling technique which I now call the "Natural"
handling technique.
This "Natural" handling technique is so universally adopted
because -
• It is simple to learn, because
o It is consistent, and
o It calls for no conscious coordination.
• With it a sailor can sail yachts, catamarans and unballasted
dinghies up to about Tasar and scow Moth performance level almost
as fast as a sailor who uses fast handling technique, but can do
this only in winds up to the design wind.
However, we can now see the disadvantages, which are that the
Natural technique sailor -
• Cannot handle with confidence in any wind any of the faster
boats such as the apparent wind skiffs or the skiff Moth or the
foil Moth.
• Cannot sail fast in any boat in winds stronger than the design
wind.
This leads to the new realization that the Tasar is about the
fastest boat that the great majority of present sailors can handle
with confidence and enjoyment.
Conclusion
The Tasar class is well positioned to grow and thrive for about
another generation, because -
• It is well managed by its members.
• It is well supported by its constructors and distributors.
• The Tasar is almost uniquely positioned as the fastest dinghy
which can be handled with confidence and enjoyment by a "Natural"
sailor. This is a new realization.
The three factors above constitute a powerful promotional platform
for the Tasar class.
Frank Bethwaite,
Designer.
Appendix 1 - Summary of "Natural" and "Fast" Handling
Techniques.
Natural Handling
1. In the Tack, Gybe and Mark Rounding turning manoeuvres, the
helm turns to the new heading, then trims sail, then hikes. Often
he/she changes hands during the turn.
I call this "Sequential Execution".
2. In straight line sailing, the helm adopts "best VMG" mode at
all times.
3. In straight line sailing upwind, the helm steers to the wind,
trims sail, and hikes as necessary. In stronger winds he tends to
clutch the sheet immobile and uses only the rudder to luff for
equilibrium in roll. In stronger gusts he luffs higher.
4. In straight line sailing when reaching downwind, the helm
steers to the mark, trims sail and hikes as necessary. In stronger
winds he luffs for equilibrium. In stronger gusts he luffs
higher.
I call this "Luff for everything".
Fast Handling
5. In the tack, gybe and mark rounding turning manoeuvres, the
helm turns the boat to the new heading at the rate of turn which
will lose least speed as compared with a rival who does not tack
etc. During the turn, he/she will trim sail and move body as
necessary to be at full hike in acceleration mode as soon as the
boat steadies on its new heading. Only when the boat is
accelerating strongly will the helm change hands.
I call this "Synchronised Coordination".
6. In straight line sailing the helm sails in two modes -
a) In Acceleration Mode when not at Target Speed.
b) In Best VMG Mode when at target speed.
I call this "Two mode sailing".
7. In straight line sailing upwind, the helm steers to the wind,
trims sail, and hikes as necessary. In stronger winds he continues
to steer to the wind, and eases and recovers sheet as necessary
both to maintain target speed and maintain equilibrium in
roll.
I call this "Simultaneous Independent Coordination".
8. In straight line sailing downwind (reaching), the helm steers
to the mark, trims sail and hikes as necessary. In stronger winds
he bears away (turns downwind) for equilibrium in roll, then uses
"steer for balance" for continuous control of roll at speed, and
for as long as the wind remains strong he continuously "snakes"
down in the gusts and up in the lighter moments to probe for and
sail at the stability limit. In this way he accelerates to and
maintains maximum speed.
I call these three related skills "Steer for Balance".
The Practical Differences (other than in light air)
9. As between 1 and 5, if we take the tack as the example -
a) The Fast sailor slows for 4.5 seconds while turning, starts
accelerating in acceleration mode at 4.5 seconds, regains target
speed at 9 seconds, then shifts to Max VMG mode. Loss to non-tacker
about 2 lengths or 4 seconds.
b) The Natural sailor slows for 5 seconds while turning, continues
to slow while changing hands, trimming sail and hiking, starts
accelerating at say 10 seconds, regains target speed at about 20
seconds if using acceleration mode, more usually at 25 to 30
seconds if using best VMG mode (which gives slow acceleration. Loss
to non tacker between 4 and 6 lengths.
10. As between 2 and 6,
a) The fast sailor sails at Target Speed for almost all of the
time,
b) The Natural sailor accelerates more slowly and so sails at the
same target speed but for less of the time.
11. As between 3 and 7,
a) The fast sailor maintains best boat speed for maximum
VMG.
b) The natural sailor loses speed while luffed. In the extreme,
the natural sailor slows to the point where he loses steerage way
and suffers loss of control.
12. As between 4 and 8,
a) in the gusts the fast sailor bears away to sail fast more
downwind, so tends to stay in the gust for the life of the gust, In
the lulls he luffs to maintain apparent wind and speed and so sails
faster more crosswind as he regains the rhumb line. In this way can
access the next gust sooner.
b) The natural sailor luffs for equilibrium, and so sails fast
across the gust with poor VMG, away from the mark and usually out
of the side of the gust. In the lull he bears away and so sails
more slowly more downwind as he regains the rhumb line
The difference between 12a and 12b in both speed, and in control
in stronger winds is huge, with everything in favour of the helm
who coordinates the three "Steer for balance" techniques
skillfully.
Summary
• "Natural" handling technique is based on hopeful optimism.
It expresses the hope that the simplest handling technique will
also turn out to be the fastest.
Regrettably, this is not true.
• "Fast" handling technique is based on measured certainty.
It expresses the certainty that efficient handling delivers faster
sailing.
As a bonus, it delivers sure control in stronger winds,
confidence, and enjoyment.
Frank Bethwaite
Designer