View Full Version : mastfoot

13th August 2007, 09:54 PM
I seem to put the mastfoot at the wrong position .the board is instabil dont go straight but jumps from right to left and back again .sometimes it goes down aswell under the waves grateful for advice.any special things to think about when rigging a "Starboard Hypersonic "229x76

13th August 2007, 10:48 PM
Hello romago,
First, a few questions so we can determine what might be causing your
How much do you weigh?
What size rig (s) are you using on the Hypersonic?
Where have you been placing the mast foot..... and why do you think that's a good place?
My guess would be you have the mast foot too far forward, plus you may not be getting back on the board and into the footstraps early enough.
I've sailed all of the Hypersonics and I never had these problems, but maybe my sea conditions were much flatter than yours.
How big is the chop and the wind waves where you sail?
As far as your "the board is instabil dont go straight but jumps from right to left and back again" I expect that is something you will have to learn.
The Hypersonic is very sensitive to rail to rail trim, and if you are at all unstable on your feet, the board will follow what your feet do, until you get your weight up onto the rig and both feet in the footstraps, then the board will go where the mast foot pushes it , with input from you (the sailor) in the form of changing rail to rail trim fo go upwind, downwind, or a pretty flat trim to go straight.
What is your skill level and what boards did you sail before the Hypersonic.
What fin are you using with what sail size?
Hope this helps,

14th August 2007, 01:31 AM
Fin :race 440 Drake
sail 6.6 North
weight 82 kg
skill: never seems to leave beginner status
waves :to high
Can you explain "rail to rail" trim and"get your weight up onto the rig"
Grateful for your replies
Best regards

14th August 2007, 03:41 AM
Hi Ronny,
OK, now we have a much clearer picture to work with:
Fin :race 440 Drake (This is OK, but for a 6.6 m2 fully planing on the Hypersonic, the 34 might be better/faster)

sail 6.6 North (Ok, this is a really good size for the Hypers!)

weight 82 kg (Ok, which size Hypersonic do you have 105/125/96/111/133 liters)

skill: never seems to leave beginner status
OK, now here's a real problem. The Hypersonics are not what I would consider "easy" boards to sail and they almost require some advanced skills.
I'm sure you've noticed that on the Hyper you need to manage the fore and aft trim (angle of the board to the water front to back) by shifting your weight. If you are used to uphauling a board with a longer nose, the biggest difference will be that you need to place your frint foot right in front of (touching actually) the mast foot, and your rear foot at least shoulders width (maybe more) back to get the board to float level front to back.
The Hypers are pretty stable at rest rail to rail due to the 76 cm width, but you do need to keep your weight in the right place rail to rail (across the board) to keep the deck flat. If you push down with your toes or shift your weight to leeward, the board will turn away from the wind. Conversely if you put weight on your heels or shift weight upwind, the board will turn upwind. Gotta find that critical place where the board is slightly nose high and level rail to rail, and stay there until you have some pretty good speed. Then things will get easier.

wind:8-10m/S (15.5 knots to19.4 knots should be about perfect for the Hyper with 6.6 m2 rig.)

Can you explain "rail to rail" trim and"get your weight up onto the rig"
Rail to rail "trim" is the attitude of the board away from level across the deck. When your board is level across the deck it has a 0 (zero) roll (rail to rail) axis trim. If you tip your board so the upwind rail ges down either by putting weight on your heels or shifting your weight upwind of the centerline, you now have an "upwind" roll (rail to rail) trim angle. As you roll the board more the board will tend to go upwind more.
Same applies if you lower the leeward (downind) rail. This give you a leeward (downwind) trim angle) and your board will tend to turn downwind until you flatten it back out to a 0 trim angle.
Are you using a harness yet?
Are you in the footstraps yet?
When you are in the harness on a high performance board like the Hypersonic, you need to learn to stop pulling with your arms, and "suspend" all of your body weight on the harness lines and harness hook.
This gets all your weight off the back of the board (your feet are still attached by the footstraps and doing the steering, but there's little or no weight on them) and puts all the force of the rig, plus your body weight as the counterbalance to the rig striaght down the mast to the mast foot. Your board is driven along by mast foot pressure.
Until you get hooked in and into the footstraps, none of this will make much sense.
If you are already hooked in and in the straps, then you need to move back on the board, to get the nose up and the board planing, then get all your weight on the harness to take the weight off the back of the board so it can plane more easily. You steer with your feet by controling the roll angle of your board.If you want to go upwind, push down with your rear heel and shfit your weight slightly upwind and your roll angle will change to upwind rail lowered and your board will head upwind.
Footing off to leeward is a little more difficult as you need to pull up with your front foot and the arch of your back foot at the same time you "unrake" your rig very slightly to move the CE of the sail a bit forward of the fin so the board wants to turn downwind.
Grateful for your replies
You are most welcome. We can work through these issues, but the Hyper is a very small platform and it will take alot of patience on your part.
If your board is "pearling" into the back of the chop, you aren't far enough back on the board to get the nose up to the normal (slightly nose high) pitch (front to back) trim angle. Try moving your mast foot back to the center of the slot and maybe a little behind the center of the slot and move your body back on the board as well. This should help alot with the nose "sticking" when you run down the back of a swell.
Hope this helps,

17th August 2007, 09:01 AM
I can deffinatly back roger up on the whole 44 cm fin thing. I don't usually use the 42 cm fin that came with my hypersonic 111 at all!. I use my 34 cm fin all the time with a 7.6 fully powered to a 5.8 juiced in lots of big chop. I would only use the 42 fin when I am very underpowered with my 7.6 and am trying to get planing... (around 12-13 knots)

As for chop, so far I have taken it out in roughly knee high (2-4 feet max) chop. The board is ok, its almost too fast in that stuff though. I hate going into chop, cause you just bounce around everywhere, and its also unnerving sailing downwind with such a short nose... I swear I have blown through a couple of smaller chop and almost eatin it on some speed runs.

As for sailing the hypersonic in general... WOW, I wouldn't recommend it either for a beginner board. I can't imagine sailing it or any other fast board out of the straps and harness. The only way you are going to feel comfertable at all especially is when you are in the straps. But try learning to get into outboard straps on a different board. The hypers strap settings are very outboard. Sometimes when I am sailing, I get a face full of spray from my heel in the water :-)

I attached a picture that I think shows the proper trim for the hyper. I am sailing reasonably powered with most if not all of my weight in the harness, pushing across the board instead of down and lifting my front foot driving the board upwind on the lift from the fin. I could let go of either arm, which I did my front arm right before this was taken. The only thing I think that is wrong is I should have dropped my front shoulder a bit more for the upwind angle I am trying to achieve.

As for tuning, I only ever have the mast foot half way up the mast track. Its mostly at the bottomish depending on how loose I want it to feel.

Hope this helps,


17th August 2007, 09:45 AM
Hi Thomas,
I can see from the photo that you are really sailing alot better.
How hard were you trying to go upwind here?
The trim of your board looks quite good, up on the fin, no splash on the upwind side of
the board.
Only thing I see here is that if you wanted to go higher, you would need to rake the rig back and sheet it in some more to close the gap and get the best upwind VMG.
Looks real good otherwise.
Thanks for your post here! It helps alot when somone who is also just learning the Hypersonic can offer suggestions.
Hope this helps,

17th August 2007, 10:13 AM
I was just trying to go upwind enough to avoid the point, I wanted to keep as much speed as possible for my downwind leg, which is the pic I attached here.

I had another question. After reading his post, I thought a pic of me trying to get a speed run downwind would help him understand how to get downwind on the hypersonic. But I am not sure of the whole stance that I took up... But not planing, I know you have to really pay attention and push the board off the wind. I found today trying some backwinded sailing that the board really likes to head upwind :-)

Is this correct for heading off downwind?

I didn't understand how to get downwind at first, and a picture of stance that a buddy of mine gave me really helped. I opted for a more Bijorn Dunkerbeck type stance. hunched up and trying to really push the board faster and put all my energy into the kit. To give you context, I was sailing close to the point at around 105 degrees to the wind (avoiding the point), so there was a lot of big chop breaking off, so I just went over an unexpected wall, hence all the spray... what is the ideal angle for speed and I guess VMG?

Hope this helps... and I love my hypersonic :-)

Once you get better romago, you will learn to love this board as a light wind weapon. It glides through lulls effortlessly and is pretty fast. I would like to get a nice S wind day (when its flatter here) and put my 7.6 speed sail on and really get some good runs.


Ellen Faller
18th August 2007, 08:51 AM
Hi THomas,
I'm sure Roger will get back to you in this discussion as soon as he can. He'll be taking a little time off away from the Forum due to a health issue, but he'll be back as soon as he can. Please stay tuned!
good sailing!

19th August 2007, 02:35 AM
Hi windsurferdagg,

(from my perspective on that 1 shot) looks like your leaning too much towards the back of your board pulling your sail too far back killing power. Front hand is too far forward too (this alone costs speed). I think your lines are too (futher back, you can handle/get more wind).
Not sure about ideal angle for top speeds, never measured it, I guess if straight across the wind is 0 and straight down 90 then it would somewhere around 25-40 (never measured it, but when I fly downwind I really lose a lot of height).

You say the shot was made at a somewhat unlucky time, otherwise I would also have commented that the board could be more leveled out from front to back. Your knees are bent and I think you are puling your front foot up (something you do when going upwind). Your front leg would normally be straight nudging the board downwind (if it doesn't feel like on the verge of catapulting it just aint right).

Your arms are bent, lines long enough/commit enough (soley) to your harness?

note to the "hunched stance":
If you don't have much wind (or you're trying to get the very last out of your sail just before catapulting) you crouch OVER the board keeping the sail UPRIGHT and PULLING (keeps board flat (minimal tail drag) and the power on).

21st August 2007, 02:39 AM
well romago, don't pay attention to my last post then... I will have to work on getting my downwind stance corrected.

Thank you duracell. My harness lines are a bit too short I think. They are max 28 inches and my boom is pretty high (around chin to nose level usually) so I get a lot of early planing and more comfert from a higher boom. As for lifting my front foot up on my downwind run, I found that it kept my foot snuggly in the strap and got my heel holding down the windward rail a bit. I wasn't really giving it my full attention to be honest. But thank you very much for the critiquing. I will try and get some more pics of me with a better stance.

tks a lot, and romago, I hope this clears up some stuff for you too...


22nd August 2007, 01:52 AM
- 28 would be just fine
- problem with boom too high is that it lifts your front foot out of the starps (which can be desirable (can))

The main thing is, keep going for it and get a GPS (it really helps verify if you're making progress or not).

Try things out and do yourself a favor: http://www.guycribb.com/windsurfing_technique_holiday_DVD_0076v01.htm
just check out ALL the articles the guy has written.

Roger is a great help too, but more "reactive" and less "proactive". So if you run against a wall ask Roger. The link provides tons of insights that will help you progress fasten than mere "trail and error".

Roly Gardner
24th August 2007, 05:16 PM
Hi Duracell

Just happened on to this thread and looked up the Cribby link you posted. This chap actually sails from Brighton I believe which is only 10 miles up the coast from me. Great info and will certainly help me cheers!