Tasar Top Speeds

Velocity Prediction Programme.

Common for yachts but almost impossible to do for dinghies, but Bethwaite has a wealth of data from full scale experiments for hull drag of various of his designs.  Using this info, and calculating the lift/drag of the rig at various angles of attack, you can estimate the boats speed in different wind strengths and headings, to produce a set of polar plots. So I did.

Hi Peaky

Using a njormal sized keyboard thank goodness this time. Mike Lyons (brought Phystique - 748 off me in 1988) knows me, so would be happy to discuss the Cirrus rig with him.

However, if from scratch the taller mast with shorter foot is the most efficent way to go if using carbon. Rumour has it the CST wing mast is to stiff and the CTech one is better if specking the mast (AUS feedback).

Look forward to seeing the boat on the Sunday of the Dinghy Show.

On another note, it might have been worth developing a boat tot he NS14 rule so that it could have an international Championships etc

Thanks for the info Barnsie.  The C-Tech mast is much cheaper too, and has an integral luff track.

I can add some definitive information, thanks to Julian and Frank
Bethwaite. The highest speed they know of was reached by Julian and
Graham Lee at Northbridge in 1980, when they reached 22.5 knots in 35
knots of wind. The results were published in Australian Sailing. Frank
calculated the speed four ways and the average was 22.5 knots (max 24
knots). The photographs in the article are totally amazing and confirm
that very high speeds were reached. The Tasar and crew were enveloped
in a cloud of atomized spray and the foaming wake extends hundreds of
feet behind the Tasar. Chris Parkinson has kindly sent me the article,
from which I am posting the photographs.

By the way, Frank's polar diagram of the Tasar in HPS1 indicates 19 knots
in 20 knots of wind at 110 degrees. The polar is based on actual speed
measurements, if I recall.

This data confirms that on a two-sail reach the Tasar hits speeds
comparable to the fastest dinghies in three sail mode.

Many thanks to the Bethwaites for this information.

Charlie

Originally posted by tickler People talk a lot about Tasar performance but I would find it hard to believe that one could get anywhere near a 505 upwind. They certainly are quick but are rubbish in shifty light stuff inland. (that is why ours is going) At the 2006 nationals in Torbay our reaching performance was fantastic...until disaster struck and I would love to try one with a taller bigger rig inland. Anyway for this year my mate has a Supernova and I have a C2 Byte so perhaps we have a chance of more success. HoweverI will never forget crewing for my son in the tasar in a big blow where nothing except a 300 could touch us.

That sounds about right. The only time I've sailed against Tasars was at Torbay Week last year. It wasn't particularly windy (say force 2-3) but they were difficult to beat upwind and although I was faster downwind if you'd messed up the first beat it would take most of the first reach to get past them all.