Design № 158
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This design was in response to a late program starting in January by Irvine Laidlaw of Singapore to build a new design 1 tonner for the 1985 Singapore Admiral's Cup team and later for competition in the Southern Cross Cup in Australia. This is the first IOR design we have done since the actual 1985 rule changes were announced in November, thus it reflects our interpretations of this year's rule, and is a development of the design theme for our two very successful 43 footers "SNAKE OIL" (Class C winner SORC) and "DRAKE'S PRAYER" (top boat Australian Admiral's Cup trials).
In general terms the approach was to develop a design that would have good all round performance with more emphasis on light airs performance than our previous designs. Our goal was to equal or better the speed of all our previous 1 ton designs in all conditions, that is to equal the extreme performance of our Southern Hemisphere 40's such as "EXADOR", "PACIFIC SUNDANCE" in moderate fresh conditions and at the same time better the performance of our smaller designs eg. "SIRIUS" (third in 1984 1 Ton Worlds), "EPIC LASS" (New Zealand Admiral's Cup team), "CARRO CHEFE" and "SAGA" (Brazilian Admiral's Cup team) in lighter conditions.
To achieve this goal the boat has a little more sail area and displacement than any of these existing designs, is almost as long as the lengthy Southern Hemisphere boats, but significantly narrower at beam waterline.
The narrower beam waterline is in response to the changed CGF formula which allows an increase in stability over last year's designs whilst at the same time obtaining a substantial decrease in wetted surface area.
Stern sections are modeled very much on those developed for "SNAKE OIL" and "DRAKE'S PRAYER" being of only moderate beam but very fair through the aft measurement stations allowing higher top speeds to be reached.
With an SHR of 15.8 some may not consider this to be a fast light weather boat. However, due to the very narrow beam waterline and the deep but small area keel and low wetted surface area hull form, the boat will be fast in light weather. Performance prediction work indicates that this design will be significantly faster in all conditions than all of our previous boats with the exception of hard reaching in heavy airs when our Southern Hemisphere 40's can just match this boat, conditions when these boats are presently considered invincible.
The rig is very much our usual fractional although the fore triangle is a little taller at the expense of some mainsail area to trade off some of this style of boat's fantastic upwind performance to boost running and broad reaching speed in light airs, the only conditions when our earlier designs appear to be a little fragile.
Construction is our normal highly developed Kevlar sandwich utilizing a PVC vacuum bagged core. This type of construction provides for a very stiff boat and clean roomy interior.
The weight is equivalent or better than using carbon fibre, the cost significantly less and structural behaviors in an overload situation is far more acceptable.
This design, like our 43 footers, should show all round capabilities with no weak areas in any conditions or directions.
12.19 m/40.0 ft
9.72 m/31.89 ft
3.99 m/13.09 ft
2.21 m/7.25 ft
6,270 Kg/13,794 Lbs
14.39 m/47.21 ft
4.21 m/13.81 ft
15.49 m/50.82 ft
5.60 m/18.37 ft
Deck Layout >
Interior Layout >
PHOTOS Click to enlarge.