Thursday, 14 October 2010

second container to Australia on its way

Last monday the second container was picked up at our factory. Another 5 boats going to Melbourne.
There will be 18 DNA's at the Australian Nationals, where several AC aces will show up.

The third and last container with another 6 boats will leave within 2 weeks. After that we will serve the European market. Two boats for Spain will be delivered at Marseille end of October.
November and December will be filled with the boats for Germany, Italy and Holland.

Thursday, 7 October 2010

Designers in action


PJ and Arno sailing in the Oktoberbokaal last sunday. Finally some time on the water.

Sjoerd's feedback on DNA

A few weeks ago PJ lend me his DNA, after I lost the Dutch Nationals to Chris Field (DNA) and Bob Baier (Niktita). I used the PJ’s DNA to sail the open German Championships which I somehow managed to win – to thankfully use Scott Andersons way of putting it- before Bob Baier and Thilo Keller. The DNA was a real party to sail. I couldn’t help to think of a major development in ice-skating (which is pretty big in Holland) a few years ago: the ‘slap skate’ (which uses a new type of blade with a bolt and hinge mechanism that enables the skater to maintain permanent contact with the ice). This slap skate totally reformed speed skating. Much higher speed was possible and old records were broken. There were skaters who accustomed themselves easily into a new way of skating and others who wondered if they ever would succeed in using these new skates. I think to some extend this will also be the case for A-class sailing and the DNA. During the German Nationals for instance it was obvious that, in some races, you could sail faster downwind while being on the wire! It was great fun doing this together with Thilo Keller, but imagine a whole fleet going round the marks this way! But even apart from this I believe the boat to faster and easier to sail then the “old stye” boats. So I pleaded PJ to just give me his boat and stop making more boats…how easy life would be!

Sjoerd Hoekstra

Tuesday, 5 October 2010

Tweaking and tuning your DNA

The DNA is very sensitive on the position of the daggerboards, on mastrake and bodyposition.
The daggerboards can be adjusted in the horizoantal axis by the glider in the hull and in the vertical axis  by adding or removing filler or tape.
Horizontal adjustment can be done on the water. If the screws are not too tight you can move the slider by pulling a board up and then by using the board as a lever to move the slider forward for less lift or backwards for more lift.
If the wind is above 18 knots the boat is faster and more controllable if you use less lift (= less rake in the daggerboards). In medium conditions you use maximum lift (standad configuration). In light winds we are not sure yet, though you have to pull up the boards while going flat downwind.
In stronger winds you are faster downwind (about half a knot)  if you pull up the luff board.
The amount of toe-in (vertical axis) differs between 3 mm and 5 mm (both boards combined).  3mm for minimum drag and 5 mm for some extra lift and height. The rule of the thumb here is that lighter guys use more toe-in. In really strong winds extra toe-in gives better control downwind , but there is a penalty upwind.  More than 5 mm toe-in feels draggy.
If the wind picks up more mastrake seems better. You keep he bows out and the boat is both upwind and downwind significantly faster. The optimal amount of mastrake depends on the type of sail and/or the battens you use.
The flatter the top of the sail the more mastrake you can use. Chris Field has used this principle to his advantage and has designed his sail so he can use maximum mastrake if the wind picks up. He uses a twisty sail with a relative flat top and a full bottom. Many other sails get very full if you ease the sheet a bit.The fuller head moves the center of forces too much backwards which leads to too much pressure on the rudders.
The amount of mastrake can be measured by holding a trapezewire on the deck at the forestay and then you look were it touches the deck at the back.
In light winds the best position is just behind the hatch, in medium conditions on the transom and in strong winds 10 cm down the transom if the top of the sail is not too full and the battens are not too soft.
If you use a lot of mastrake steering may improve if you put the rudders somewhat less under the boat. (standard 15 mm)
This weekend PJ sailed in Hellevoetsluis in force 5-6 in such a set-up (increased mastrake, striff battens) and he could easily beat a Nacra 20 carbon and the F18's  upwind  by saling both higher and faster (downwind the Nacra was a rocket). Downwind he struggled a bit due to very nasty waves. In such waves you easily loose the rhythm, where the spinnaker boats just glide on.
A few weeks ago Chris Field could match the speed of a M20 in medium to strongwinds on flat water after increasing the mastrake on his DNA.

Body position on the boat is critical as well. If you stand too far behind the transom sinks and you will be slow. The boat will saill at 9-10 knots upwind. The fastest way is to play with your weight a little bit; you step forward if the boat is picking up up speed and once it is up to speed you step a bit backwards and get the boards working for you. (speed 12-13 knots) If you step back to early the boat is too draggy and you cannot get the boat over the  threshold of 10 knots.
Downwind the same principles apply. It is easy to get the nose out of the water, but the fastest way is to get the nose just touching the water. Troubles (steep waves) are circumvented by increasing the heel of the boat, though generally the boat is sailed flatter downwind than the previous A-cat designs.
The boat asks for a more active (fysical) style. You really have to work the mainsheet to get the best out the boat and you have the move your body as well. You can see that style used by Chris in the pics taken at the Dutch Nationals. Sailing the boat in medium conditions is quite easy, but in strong winds you really need to master the boat to get te best out of it. The reward is huge though because Chris reached amazing endspeeds and downwind he sailed away from the others both in Garda and in Hellevoetsluis.

It will be interesting to see which sails Landy, Glenn and Stevie will use in the Australian Nationals and how they will sail the boat to get the most out of it. Three sailmakes which differ both in bodyweight and in rig philosophy.

Friday, 1 October 2010

Olympic multihull event

The ISAF has to decide within one year which events (classes) will be in the 2016 Olympics. The return of the multihull event is most likely.
Two questions are to be answered
- Do we want a multihull event in the first place?
- What class should it be?

Multhull sailing is flourishing so we clearly do not need the Olympics to bring the sport to half boat sailors and the general public. So the answer for the first question is ' be careful what you wish for'.

In my opinion there are not too many good candidates for a new multihull class. If a F18type is selected that would ruin the current F18 class. The Tornado as a design looks outdated.
The Tornado would be suitable for the sailors but is no longer the best boat to promote the sport.

If we want a multihull in the Olympics I would like to see a state of the art design with the same or better building quailty as the Tornado. A lighter better looking boat built in carbon-nomex with curved foils and  an up to date wing profiled mast (not a wing). Carbon beams, composite rigging, double trapezing  suitable for both boys and girls, fast in light and strong winds, suitable for lakes and seas.

I think the class is best off with a Marstrom like builder. A boat builder who builds a limited amount of boats for the class each year. A high tech economic boat. Economic because it lasts at leasts two campaigns.
For manufacturers as Hobie and Nacra such a class does not make much sense because sales are limited and the class will not grow much outside the sailors who want to qualify for the Olympics.

If a new class will enter the Olympic arena depends heavily on what the ISAF wants and more important what ISAF does. Time is limited for a trial and a trial only makes sense if there is some consensus about the parameters of the new boat. To set these parameters ISAF has to do its homework, comparable to what BOR did in selecting the new AC multihull.

Sloppy homework by the ISAF can lead to the selection of a Hobie Tiger or Wildcat for the Olympics. That is neither in the interest of the sport or the manufacturers themselves. Vanity might lure Hobie (or another manufacturer) into this trap though.
ISAF is still convinced that the sport is best promoted by spreading olymnpic boats over the globe.
The reality shows that the number of sailors in the Olympic classes is low and that Olympic classes seldom grow outside the traditional sailing countries.
To promote the sport you have to focus on growth of the international classes.

The relevant distinction for ISAF is not cats vs dinghies, but high perfomance vs boring slow and outdated.