Sport Today

Hi!

I have got several informations that don't 'get on well':

1)According to what I can read in the mags, Professional windsurfeurs
usually
handle 1.5sqm more than us mortals.

2)According to the same mags, a too big sail is not faster than a right
sized
one, as it generates more drag. this does not work with the first
assertion!

3)Race sails are made to be sailed overpowered and trimmed quite flat
for
less drag, thus more top speed. Are they still faster than a lower sail
rigged less flatly?

So what?

Sure a smaller sail allows easier maneuvers.
However, I'm really confused with the choice of a sail according to
given
conditions.

Specifically my problem is when to rig my 8.4 or 7.1.
Last time it blew 22 knots, I was using the 8.4 and smoking most of the
guys
with 7.0m, but sometimes the speed was way over my abilities (I was
praying
"please no spinout, please no wipe out, it's gonna hurt...").
If I could have them both rigged I'd have compared but I can't!!!

What is the right sail size/ power/ drag ratio for a given wind speed on
flat water?

Christophe

22 Knots = Force 6, with 8.4 metre sail??? You're a braver man than me.

As for the sail choice - depends how much of a speed freak you are I guess.
If you're that out of control there's no way you'll get around a corner. I
should stop worrying about it, and go with whatever you're comfortable with.

Mark

You're right, these are mph on the scale I have :-)

However it's a Hot Mach 2, and has the most stable profile I have ever
tried
when overpowered (compared to my previous freeride/free race sails).

Specifically my question is a 7m race sail tuned for "not that big
conditions"
as/less/more fast than a 8.4m tuned for high wind?

One of the reasons racers use "too much" sail is that if they aren't still
WAY powered in the deepest lulls, they get passed by the people who are.
Then they just tolerate the excess power -- and drag -- in the gusts, and
sometimes get eaten in the process. One's balance between the time spent
"fighting for his life" and the time spent slogging is a personal choice,
affected by the wind range common locally.

If flattened-out race sails didn't have a greater overall windpower range
and/or greater ultimate speed (OK, and greater upwind ability) than deeper
sails, who would use them? While a deeper 7.0 might out-accelerate a flatter
7.0 coming out of a wind hole, the flatter 7.0 should generally remain
stable and controllable when the deeper sail is hitting a speed wall or
eating your lunch, and the upper end range gain should exceed the lower end
loss, else why bother with race sails (OK, to point higher).

So it's back to basics: Each of us must weight all the pros and cons of each
type of sail (and board and venue and fin and harness) and decide which
suits our needs best. With sails, the factors include price (racy sails
generally cost more), rigging and unrigging ease, handling, power, speed,
durability, ancillary expenses such as special masts, sailing style, rider
skill and preference, wind range and quality, venue (no big luff sleeves in
breaking waves, for example).

The bottom line is that there is no "right sail size/ power/ drag ratio for
a given wind speed on flat water" any more than there is a "right" board or
a "right" automobile. It's all about choices. Only after one specifies his
criteria can he narrow his sail options and even to begin to identity some
"right" sail type and size.

I once sailed Howard Park on Florida's west coast in solid 3.7 offshore
winds, on water as flat as a fogged mirror (it was knee deep). One guy was
getting 6 feet of air under his fin, another was trying unsuccesfully to
spin out (it seems there must be some surface irregularities to spin out),
then taking advantage of the traction to see just how tight/fast a jibe was
possible), so flat water doesn't rule out B&J sailing. And sails full of
cambers impede B&J sailing. Surely at 22 knots there's chop and swell
available in most places, so sail choice is complicated by sailing style
options.

Mike \m/
To reply directly, remove the SpamDam.

You're conclusion only holds in clear air and water. Racers are very
concerned with getting a good start, punching through turbulence (both
air and water) at the start. They are also concerned with variable
conditions. It may be slower to be on too big a sail when going head to
head with someone, but it's even slower to be underpowered for even a
minute portion of the course. As a result, racers tend to rig insanely
big, holding on in the gusts, so they can power through the lulls.

Depends on your point of sail. Going upwind, the larger flatter sail
will give you better angle, thus better VMG.

I assume you're talking about mph, not knots. If you're 'smoking'
people, the combination couldn't have been that slow. The question,
though, is whether it was the speed that was more than you could
handle, or whether it was the power you needed to control. Fear is a
good indicator that you're going faster on a given setup, but that
doesn't mean you couldn't go faster on a different setup. BTW, if you
feel like you're getting way out of control on your larger sail, try a
slightly smaller fin and a little more downhaul, and drop the boom an
inch, before you spend the time rigging a smaller sail. You'd be
surprised how much more controllable that can make your whole setup.

Andreas

Sent via Deja.com http://www.deja.com/
Before you buy.

When my wind-ometer reads steady over 20,   Im riggin 6.0 or smaller.

Yeah, if I get caught out there on my 7.8, with big gusts to 25 I can
hang on, but it's a LOT of power, and I'm on my way in to re-rig in a
hurry.  

Indeed, yes, it was mph.

I actually did what you're saying: I went down from 50cm to 44cm, which
changed an horrible-jumping-everywhere-tailwalking board to a quite
easily
handling one. At the same time I downhauled to max and gave a bit more
outhaul.

However it was a bit of survival during the gusts :-)

So this is a racers' way of surfing: don't wanna slog one second ;-)

thanks to all for the explanation!

Christophe

I'm with you on that one Mark, >20 is rare enough in the UK, I'm not going
to waste it struggling with a giant rig when I could be using 5.5 and a
sinker, going maybe 2knots slower, and making my gybes (which is worth about
800yds if you're concerned about burning people off), waterstarting in 1
second, etc, etc. Anyone who has learned to get into the straps can go fast
in a straight line on flat water with a rig thats too big. The moment there
are any bumps I'll fly by the big rigs unless they are semi-professional
racers, in which case they'd be going by me if they rigged small, too.
Basically the best sailors go fastest regardless, so hats off to Christophe,
the guy must be good. (but don't tell me that the racers rig those enormous
sails if they just want to go out and have fun)

Regards

Tom

Hello Christophe,
I've been watching the replies on your post, and while all of
them contained some good advice, I'm not sure anyone has
answered your questions directly or completely.
So, I will try to clarify.

Yes, given the scenarios you describe, your "several bits
of information" seem to indeed contradict each other.

Yes, this is true! Sometimes even bigger. But their main focus is
maximum speed upwind, and the ability to plane fast as far off the
wind as possible.
In order to do this they will flatten their sails ridiculously
using an adjustable outhaul and way more downhaul than most of us
are willing to try.
Why? So they can get the fine entry angle, with lots of top twist
and a nice straight leech to maintain good spanwise flow, enabling
them to go much higher upwind, at incredible speeds to get to
the upwind mark first.
And it's a game of bigger/flatter is better, and the racer who can
hang on to the biggest sail will usually win.
You don't hear about the racers who took too much sail, because they
usually don't finish well. But racing is so competitive at that level
there are many top racers who can and will find a way to hang on to
a sail that recreational sailors would never consider using.
Andreas had some good points about starting line turbulence,
and having enough sail to stay on plane through the lulls.
It's all about winning, whatever it takes to do that.

This is correct, for normal back and forth reaching. But it's not
applicable to racing, as there is far too much variation in windspeed
over the course of a race, and once again, upwind is everything in
racing.

It does when you consider all the factors involved in racing vs the
limited number of factors required to reach back and forth at the
recreational level.

Yes, but this has to do with the tremendous amount of apparent wind
a good racer can generate by heading very high upwind.
These same sails may not be a whole lot faster just reaching back and
forth like most recreational sailors seem to do.
If you have not raced, or been to a World Cup or National Championship
level race, you cannot conceive how high and how fast these guys can
go.
A good comparison would be to look at your local dirt track racers
in stock cars, and compare that to Formula 1/ Indy Cars/ or NASCAR
racers at Daytona. BIG difference.

On what point of sail? Were you pinching up higher than they were?
Or were you bearing off deeper than they were.
How flat did you have your sail rigged? Lots of dowhnaul, lots of
outhaul?
You can tune almost a full meter out of most modern sails by
using extreme amounts of downhaul and outhaul.
Perhaps you had your 8.4 tuned down to something like a 7.5.
This sounds far more consistent with sailing in 22 knots.
Are you using the correct mast so the sail twists off progressively
as it's supposed to, or some other mast that could be dumping the
entire top of the sail off, way too early, effectively reducing your
sail size significantly.
Are you a larger sailor?
This can be a huge factor in how much sail you can hang on to.

What is the accuracy of your wind measurement system?
Did you measure this 22 knots on the water, in exactly the area
you were sailing and at the same time you were sailing?
This can make a huge difference.

As was stated by all the top pros in the Peter Hart video about the
speed trials at Fuerteventura several years ago, "Comfortable is
Fast".
So, if you are comfortable on your 8.4 in 22 knots, they you have
the right size sail for you, in those conditions, with that board and
fin. If you are going faster than the others, then you must be
comfortable with your setup, even though you are going scary fast.
If everyone else is faster than you, maybe you need to do some tuning,
get a little larger rig, or work on your "fear factor'.
Hope this helps,
         Roger

--
sailquik US 7011
Sailworks/Starboard/F2/MPB/System B/True
Ames/Chinook/Kokatat/Da Kine

Sent via Deja.com http://www.deja.com/
Before you buy.

I think you misunderstood!

My point is not to say "Hey guys, have you seen what I can do?", but
rather
to understand the mechanics of sail sizing and tuning, and what is the
purpose
of flying a (too) big sail. I can't see any other way than
experimentation
for that purpose.

However it may be good to sail sometimes overpowered to check one's
limits
and enhance one's abilities.

By the way I also prefer riding my sinker and a 5.9 camless sail :-)

Christophe

Yes, when racing on courses involving upwind and downwind legs. To a
lesser degree also in slalom and competition wave sailing. But many of
them (personal experience with Eric Thieme, Josh Stone, Francisco Goya
and some more, all about my weight) use surprisingly / frustratingly
small gear when freeriding (i.e. not competing), still being quicker.

Right. But a sail which lets you drop off a plane or leaves you without
power in critical situations is way slower in a competition. Besides
that, the speed argument is most important for reaches, not
upwind/downwind. A bigger sail is also of some value for better
acceleration at the marks.

Yes. Big, with lots of twist and trimmed flat (or with adjustable
outhaul) is the best compromise for racing. But handling and such things
don't count there and the top boys ussually have their jibes wired on
anything.

--
Wolfgang

Christophe,

I couldn't resist the hats off rhyme, sorry.

I take your point, and stand chastened. I guess that in my part of the world
20+ winds are sufficiently rare for this weekend sailor with other demands
on his time (the snapper and the prawns) that I always look for maximum
immediate enjoyment so the idea of trying to use a giant sail when a smaller
one would work is incomprehensible.

IMO the difference between a 7 and 8.4 is not that great and other variables
such as downhaul, board, fin, rider-weight and skill are likely to outweigh
that difference. Pulling the sail flatter permits a higher top speed and
better pointing because the apparent wind can move further forward yet still
enter the foil smoothly. SO maybe the 7m guys are rigging fuller foils
because they need more grunt in the lulls from their smaller sail, but that
reduces their top speed in the gusts. That said, in a typical 22 wind a 7m
should still be planing in the lulls even if rigged flat. Maybe it was
gusting 22?

Regards

Tom

Christophe,

I'll back Roger up on that one. I went to a world cup event.... There was a
major swell running, several feet, the winds were very marginal, probably
about 12mph average, and these guys were absolutely flying. Giant rigs,
sails with no clew-tape and reduced batten-tape to reduce weight and
probably more importantly drag, expert pumping off the gybes, boards that
practically have to be tethered to stop them from floating up in the
air......Only the logos are the same as the kit we buy, but this kit would
not be appropriate for recreational sailors or for fun racing. There was a
dumping shorebreak that 95% of sailors would not handle, and these guys were
taking this *** kit out through it as if it wasn't there.

I'm not sure that any of this is relevant to your queries except to concur
that pro racers with giant rigs are not playing the same game as us.

Regards

Tom

Hi Roger,

Thanks a lot for your and the others answers.

Well, I was going for max speed on a broad (that about 100-120deg, isn't
it?) reach then rounding upwind to a beam (90 deg) reach when getting
out of control.
I was sort of working on my 'fear factor' :-)

max downhaul, but not completely outhauled (2cm more than low wind
conditions)

This was actually 22mph, not knots. This was an average measure, on the
beach.
It was recorded by the anemometer recording the wind speeds for phone
consulting. The wind was quite steady.

The mast is of the right IMCS, but only 60% of carbon which isn't that
much
on a full-on race sail.

I'm 84kg/1.88m

'comfortable' is not the word I would use. 'On te edge' would qualify
the situation. However my board is a Bic Vivace 299 (149liter/59cm),
which was
too big for the conditions, despite flat water. I found that it was
hitting
the chop quite hard: This may be due to my mast foot set almost at the
front
of the mast track.

Thanks for the infos

Christophe

I'll have to see that!
Videos do not give such an impressive view of race!