PDA

View Full Version : hypersonic 105L


raggy
19th December 2007, 09:39 AM
Hay guys I have just moved from a 123L carve & a 135L formula to a 105L hypersonic
the thing is that when I beach start it tends to round up on me.
once on the plain wow its fantastic.

thanks.

crazychemical
19th December 2007, 05:53 PM
can you explain what you mean by it rounding up on you? Maybe you just need to place your rear foot more towards the centre of the board ...

raggy
20th December 2007, 04:57 AM
Hay It rounds up in to wind almost like I have a lack of mast foot pressure at that time
it's just stumped me as my other boards dont seem to have the same treate
I mean I know it's me just cant work out if I have to do some thing a little different
it's as i come up on to the board after a beach start once plaining its fantastic.

Roger
20th December 2007, 08:14 AM
Hi Raggy,
I think the reason you feel there's no mast foot pressure is because there really isn't any until you get up on the board, sheeted in some and hooked in.
Yes you can "steer" your board by pushing/pulling the rig to get it lined up correctly for a beach start (or a water start for that matter as it's really doing the same thing) but that's not true "mast foot pressure" as we speak of when you are up and planing, back in footstraps and hooked in.
So, my first (and perhaps best) guess is that you have somehow learned to position your board and push the rig up for a beach start and in this process you are depending on a little bit of "nose bite" (along the water line up forward from about the mast track and forward to stabilize the board's direction relative to the wind direction.
Unfortunately the Hypersonic is so short (and the nose is even shorter relative to the mast track position) that I think you probably aren't getting the same reaction from your board, so as you go to step up, it pulls under you a bit.
Also, as CC mentions, you may not be getting your foot near enough to the center of the board, so the board is responding to your foot being upwind of the centerline (the board is tipped slightly upwind rail down) by rounding up into the wind.
I'd suggest that you start off with the board pointing a little further off the wind. This will help until you adjust to the super short length and fairly wide width of the Hypersonic.
It's very different than your Carve, but I would think might have encountered some of the same issues on your Formula 135 ltr.
Hope this helps,

raggy
20th December 2007, 10:20 AM
Thanks Roger I am starting to think it's just going to mean some dedicated beach start
workouts marry xmas and happy sailing..

Lessacher
8th January 2008, 12:47 AM
Hallo raggy! I used always a 28cm weedfin, rake 45°. More time to come in the footstraps.And be sure , a weedfin is not slowelier. Read Martin van Moers: With a
rake 30° fin over 50 knots. I started always with my frontfoot in the footstrap, later with
the back foot. If it worked, okay, if not, good night.It was the board where I needed
th most pressure of my frontfoot.I think that it is easier for Roger to write something,
why it is easier with a weedfin.Please Roger and thank you.
Roger: Is for you a rake 30° fin a weedfin???????? Wolfgang

Roger
8th January 2008, 07:44 AM
Hi Wolfgang, and raggy,
I don't have any real scientific basis, but I've always found that a 40°-50°Leading Edge (LE) weedfin to be more "forgiving".
You don't have to be quite so precise with the pressures and angles when you have the swept back fin with more area.
Do I consider a 30° LE fin a weed fin.....?
No!
I do know that a 30° LE is a Wolfgang Lessacher "Speed Fin" design, and has to be one of the fastest speed fin designs ever developed, especially when you put it under a board that Martin van Meurs is sailing.
But I don't think a really small fin (28 cm is small) will help raggy with his speinout problem until he learns to stay off the fin until he gets the speed up.
Then, like all tiny speed fin designs, you can hammer away on the fin.
But you have to get up to some speed where the little fin can develop enough lift to counteract a heavy rear foot.
I always just tried to "pressure" the fin a little as the speed increases, but if the fin feels
soft or kinda "mushy", I back off the pressure and gain a bit more speed and try again.
When the fin locks up solid, you can feel it, and then you can really push on even a very small fin.
Of course, on the courses that Martin sails, (i.e. beam reach and lower) you don't really need to push the fin much at all.
If you are sailing and trying to "go deep" you almost have to back off the fin pressure quite a bit to get the board to turn off the wind.
Hope this helps,

Monty
12th February 2008, 04:14 PM
Hi Wolfgang,
with a focus on optimum speed, what would your recommendation for weed fins be for the following;
Hypersonic 105 with KA Koncept 7.5m sail
Sonic 85 with Severn SSR 6.6m sail
Sonic 85 with Severn SSR 5.6m sail
Thanks

Lessacher
16th February 2008, 01:14 PM
Hallo Monty! With the Chamäleon 24cm made Dieter Gerichhausen 38,6 Topspeed. Ranking
place 87. Robert Seinen used a new rake 30° fin 25cm and made over 37 knots.
Wolfgang

Roger
16th February 2008, 10:07 PM
Hi Wolfgang,
What sail sizes did Dieter and Robert use to post those speeds.
These speeds were both on Hypersonics?
Thanks,

Lessacher
16th February 2008, 11:44 PM
Hallo Roger! Dieter used F2 Thommen 270 with Stealth 7.0m²
Robert used at Jan.21 Tabou Manta 49cm with Vapor 5.5 topspeed
was 39,7knots. My topspeed with Hypersonic 105 was 32 knots , fin
was 28cm Duo Weed. Sail was with 7,6 m to big. Wolfgang

Roger
17th February 2008, 10:12 PM
Hello Wolfgang,
Yes, that's what I was thinking.
The Hypersonic, (which is the board that Raggy is asking about) needs a little more fin span than the F2 Thommen and Tabou Manta (49 cm wide) because the Hypersonic is much wider.
You might get away with a fin smaller than the 28 on the Hypersonic, but you'd have to really stay "off" the fin, especially when getting the board to light up.
For Raggy,
I just noticed that you are asking about the 6.6 and 5.6 m2 rigs on a Sonic 85.
For that board, I think Wolfgang's recommendations on the fins Dieter and Robert used would be applicable to your Sonic 85.
The Hypersonic, with a 7.5 m2 rig, would require at least the 28 cm Duo Weed and you could probably get even more speed with a 28-30 cm 15 deg. LE speed fin.
Hope this helps

Jean-Marc
20th February 2008, 05:07 AM
the thing is that when I beach start it tends to round up on me.
once on the plain wow its fantastic.

Raggy,

Please check out a short movie while beach starting the HS105.

http://fr.youtube.com/watch?v=pbsdR59Ogcs

You can see at 00:02 that the board tends to point upwind too much. The reason is that I had just a tad too much heel pressure on the windward rail, thus banking the hull upwind. I compensate this luffing up by tilting the rig a bit forward and keep the board as flat as possible.
Having started the planing and just after stepping my front foot into the front footstrap at 00:08, I moved my back foot outboard just in front of the back strap but with a tad too much heel pressure on the windward rail at 00:09, which makes the board quickly luffs upwind again.

So the best advice is try to keep the board as flat as possible on the water when starting the planing. Try to avoid banking the board with heel pressure.

Cheers !

JM

Philip
22nd February 2008, 04:56 AM
JM, outstanding videos on that link. The slalom vid. embodies what for me is the essence of WS. Sound track is a perfect match too.