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View Full Version : Antoine Albeau burst of speed?


nonopr
20th July 2009, 01:12 AM
Why this guy can go past anyone at anytime? What does he do to get the burst of speed he get to pass people like they are standing still?
Can anyone explain?

Maximus
20th July 2009, 07:06 AM
Baked beans

nonopr
20th July 2009, 10:12 AM
Jajajaja, Funny. But not the answer looking for.

davide
20th July 2009, 01:37 PM
Jajajaja, Funny. But not the answer looking for.
I am not sure it can be explained ... many sports have athletes that dominate the field for a a few months, a season, or years. Think Eddy Mercks, nicknamed the cannibal, who dominated bicycling for more then a decade; or Bjorn Dunkerbeck that did the same in windsurfing for almost ten years, examples can be found in pretty much all sports. Strangely enough it seems to be almost the rule in solo sports: one person finds a magic balance and the rest of the field is just those few steps behind that are enough to lose a competition.

Screamer
20th July 2009, 03:32 PM
or Bjorn Dunkerbeck that did the same in windsurfing for almost ten years

Correction: Dunkerbeck won twelve overall pwa titles 1988-1999.

Unregistered
20th July 2009, 04:46 PM
Doesnt explain everything by along way at all but weight has a great deal to do with it .Its a prerequisite that all top sailors are super super skilled with (I suspect) little in technique between the very top...... But when you get a real powerful heavy bloke with equal (or probably superior) skill he(or she?) can exploit the physics in our sport.
If there`s enough power available to get heavier sailor well powered/over powered and the kit is stable etc the heavier sailor does have (relatively) less drag for the power he can put through board; hence he can get that extra speed. (Look at most speed records)

Lighter sailors will always have (???) better power to weight but heavier will better power to drag. (Assuming equal all else ;which is never the case ???)

Watching sailors this is sort of demonstrated. But there is so much going on the physics can end up playing a less than deciding rule. Lighter sailors plane up quicker;accelerate quicker but ultimately heavy sailor is going to get you !!!!

Watched Antoine last year; seemed to me he could muster up another 1k or so board speed (over others) whenever he wanted ??? He must have some good knees !!!!

Its my thoughts anyhow !!!

Deja Vu
20th July 2009, 10:04 PM
Jim Drake wrote an article about size and leverage a few years ago. Apparently as size increases so does drag (as you would think); however, leverage increases more than the drag (a 3:2 ratio if I remember correctly in favour of leverage). The bottom line is that size does matter - how much I suppose depends on skill level, equipment, tuning and obviously conditions. Robby Naish also wrote an interesting article about racing the big guys. He said that once the big guys were able to gybe really well he had more and more problems staying ahead. They had a substantial advantage close to the wind, but he could neutralize the "size advantage" by bearing off the wind onto a broad reach. Dave White claims size doesn't matter! Why does he weigh 300 lbs. then?

davide
20th July 2009, 11:33 PM
Doesnt explain everything by along way at all but weight has a great deal to do with it .

Not really: most PWA top slalom racers sailors are in excess of 200 pounds, I think to rememer that Bjorn is actually heavier then Antoine.

Unregistered
21st July 2009, 12:58 AM
Its an iteresting thread and obviuosly drag increases with an increase in weight but its not a proportional increase. In other words doubling the weight will not double the drag. If this were not the case wearing a weight jacket would not increase top speed.The extra weight has to be positioned to also increase the force available but wearing a 20k weight jacket would not increase force available by 20k. (Look at dynamics of weight and forces/vectors)

If heavier sailor did not have better weight/drag ratio how come all top records are held by "heavy" sailors.If Jims expanation re- leverage were only concept involved speed sailors would be tall and light ???
Its best explanation I`ve read but it was written around slalom water skiing and tow line forces for different weight skiers. Yes its different but priciples of drag would be same ???
I`ll Try and find it out again.

Load a dive Rib up with well over double weight of boat and it will reduce top speed but if drag had doubled top speed would be halved ?! Its not. ??? Probably irrelevant though ?? But I dont think drag has a direct correlation with load. ???!!!
Any Hydrodynamists ???

Deja Vu
21st July 2009, 01:21 AM
Not really: most PWA top slalom racers sailors are in excess of 200 pounds, I think to rememer that Bjorn is actually heavier then Antoine.

This may not explain why AA is so fast, vis a vis his competition, but the fact that most of the racers weigh in excess of 200 pounds is a pretty good indicator that if you want to compete at the top level you need to be big - in other words you need a lot of leverage! In AA's case I suspect he wants to win more than anyone else so he's willing to push his immense talent and size to the limit.

The words "performance, information, beer, deer, moose, sheep" etc. are all collective nouns (meaning they are pronounced and spelled the same whether referring to one or several). There is no "s" added! "Beers" is so commonly used now that there's no point arguing about its usage and no doubt the other words set out above will go the same way. When "mooses" becomes a common word in the English language I'm jumping off a bridge.

davide
21st July 2009, 01:24 AM
Its an iteresting thread and obviuosly drag increases with an increase in weight but its not a proportional increase. In other words doubling the weight will not double the drag. If this were not the case wearing a weight jacket would not increase top speed.The extra weight has to be positioned to also increase the force available but wearing a 20k weight jacket would not increase force available by 20k. (Look at dynamics of weight and forces/vectors)

If heavier sailor did not have better weight/drag ratio how come all top records are held by "heavy" sailors.If Jims expanation re- leverage were only concept involved speed sailors would be tall and light ???

I think you are missing a big part of the equation: strength. Think how much strength it takes to go around a slalom course with a 8.0 sail in 25 knots, or with a 6.0 in 40 knots ...

And of course a 200-230 pound man is going to be way stronger than a 160-180 one, it is not simply a matter of weight, and that is why a weight jacket can only go so far (put 40 pounds on a 160 sailor and he would be dead on the water). It is instead a matter of sheer strength and having legs like trunks and torsos/arms that can keep everything nice and steady. Like in boxing: a middleweight cannot dream to compete with a heavyweight.

PS by the way: all top PWA slalom sailors are more then 200 pounds, Bjorn is actually heavier then Antoine.

Unregistered
21st July 2009, 02:10 AM
Found this

Components of planing hull drag

The planing hull equilibrium described above shows us that trim and lift are interrelated. Trim affects lift, and it also affects drag. In fact, trim determines drag, as we will see below.

(Note: This describes the drag on the hull only. A boat in service will have additional drags due to appendages, seas, and shallow water. It might also have devices such as trim tabs that will also affect drag. These are not treated here.)

Planing hull drag is made up of four principle components:

Pressure + Friction + Spray + Windage

Windage drag is the air resistance of the exposed hull that is driven through the air. It has the tendency to increase trim. More windage area means more drag and also more trim.

Spray drag, sometimes called whisker spray, is the drag of the hull driving through the mass of the spray that is produced ahead of the boat. Evaluating the effect of spray is complicated and is often neglected, as well-designed spray rails or strakes can be effective in moving the spray away from the hull rather than leaving it in front of the hull. Like windage drag, spray drag would contribute to greater drag and trim.

This leaves Pressure drag and Friction drag as the two parts of our planing drag analysis. The planing hull analysis that is used here is a modified version of the well-known Savitsky prediction method.

Savitsky prediction method

The Savitsky method poses the bare-hull planing drag as

Bare-hull drag = Pressure + Friction = L tan(τ) + CF ρ S V2 / cos(τ)

where,

L = lift on the planing bottom (nominally the boat weight)

τ = dynamic trim angle

CF = frictional drag coefficient across the wetted planing surface

ρ = mass density of the water

S = wetted planing surface area at the particular dynamic trim angle

V = mean water velocity across the wetted planing surface

The important bit being
Bare-hull drag = Pressure + Friction = L tan(τ) + CF ρ S V2 / cos(τ)


The drag is composed of 2 parts (They are sying Pressure + Friction)
The boat weight (Load L) is only involved in first part consequently increasing load (L) will NOT increase overall drag by same proprtion. (As long as planing is maintained)
I think !!!!

Unregistered
21st July 2009, 06:29 AM
moving swiftly on.......if the fastest sailor is doing 40knots to my 33 when the wind is Force x, will I be doing 40 when he is doing 50 in a Force 9 ?

Farlo
21st July 2009, 10:25 PM
Deja vu or anyone, the article from Jim Drake on windsurf physics referred in post #7 was very interesting. Unfortunately it seems to have disappeared from the site. Does anyone know where I could find it?

Deja Vu
22nd July 2009, 07:15 AM
If memory serves me correctly, the Jim Drake piece appeared in the U.S. magazine called Windsurfing about two, maybe three years ago, along with the Robby Naish article.

Unregistered
22nd July 2009, 01:28 PM
re: "Dave White says size doesn't matter; why is he 300lb then?"

Because he's a Fat Fu... I mean, because he ate ALL the pies!


(he's fu...in' fast, though!)

Unregistered
22nd July 2009, 06:43 PM
I have played with my weight for years..... I have been 120 kg and I have been 83 kg.
My personal conclusion is to be around 90 kg, but windsurfing in general I have most fun when I am between 80 kg an 90 kg. When you are lighter it is much easier to stay fit, the accleration is much better. I have been sailing since 1981 the equipment we have now is so much better... The advantage of beeing heavy was much bigger before!

The right set up regardig fins and mast stiffnes and size on board and sail is way more important!

Look at Karin Jaggi doing over 40 knots with the right set up at 63 kg.....

Deja Vu
23rd July 2009, 01:00 AM
Where are all the light guys in the top professional ranks? Twenty-five years ago the light guys dominated (Robby Naish, Alex Aguera*, and Alan Cadiz). Where are the 170 pound guys now? Along with weight comes strength and the ability to hold down larger sails. Fifteen years ago Dave White weighed a fraction of what he does today and he wore a weight jacket when he competed with little success in speed contests. Today he doesn't need a weight jacket and at 300 pounds he holds production speed records. Robby Naish was able to do 43 knots, but this is a long ways away from AA's 49+. Weight doesn't matter? I've lost nearly 25 pounds and I know it does matter!

* He wrote one of the best articles on "speed technique" I've read, which was published in the April 1988 issue of WindRider magazine, and is still very relevant today.

michelb
23rd July 2009, 03:11 AM
But also in marginal winds with this 11 kg less is more easy to take off.
But agree that when you have 25 knots in 10 sqm sail, is better to have it.

Farlo
23rd July 2009, 11:58 PM
Hello Deja Vu, I remember a very informative article of Jim Drake on the Starboard web site. It might be the same than the one published in US Windsurfing magazine. It was also a few years ago (may be a bit more than three but not much). Since it has been removed I was not able to locate it again. Has anyone kept a copy?

Floyd
24th July 2009, 02:27 AM
Weight does have a great deal to do with it. Definitely.
Sort of agree with earlier poster re-heavier sailor having relatively less drag but not quite for same reasons.
Imagine heavier sailor is matching lighter counter part at say 30knots. Heavier sailor will need proportionally more under hull area to support extra mass; but drag is a function of area (for friction) and trailing edge lenght.(which is constant) A gust occurs; heavier sailor is able to take advantage (with his extra power) and his board accelerates. The extra speed will reduce surface area required to support his mass; so he will accelerate until drag and power are balanced again.He does have equal drag now to the lighter sailor but is travelling slightly quicker. (ie his weight only increases frictional water drag and not trailing edge drag;or aerodynamic drag which no one has mentioned !)

Heavier sailors definitely have relatively less aerodynamic drag which must play a part. (Its why down hill skiers also tend to be heavy; they have faster terminal speed !)

To my mind Antoine is heavier than equally skilled and more skillfull than equally heavy. (or heavier)

Bjorn is heavier than Antoine but not sure he should be ! In his "heyday" he was 95k !
I suspect Antoine has better body mass index. (At moment) ie suspect Antoine is the stronger !!!

Has Bjorn put weight on to go faster ????

Unregistered
25th July 2009, 12:28 AM
you guys forgot the factor of a good setup of the board and sail
and these np race sails are really fast this year!
:-) chris

Unregistered
25th July 2009, 12:53 AM
We could all get that and not catch any of them let alkone Antoine !!!

Deja Vu
25th July 2009, 01:48 AM
you guys forgot the factor of a good setup of the board and sail
and these np race sails are really fast this year!
:-) chris

It'll be interesting to see if any of the other sail manufacturers copy the NP sails or if some racers not on NP sails move over to NP. That's what will give us, at least, some indication about just how good the new NP race sails are. I'd love to know what some of the top racers thought of their competitors' equipment.

Ken
25th July 2009, 03:08 AM
There are several great slalom boards and sails, it's the "driver". Slalom depends so much on a good start (sailor skill) and managing the demanding conditions (sailor skill and board?) that the PWA has been racing in this year. To be the best in slalom, you must be consistent, sometimes getting blown away by a faster sailor that hit everything exactly right, but it's finishing at or near the top in the majority of the races that determines who's the best. That's skill, not equipment.

Sails have little to do with Antoine's success and I doub't that anyone will copy NP race sails. Too many other sails that are just as good or better. Antoine would win on any of them.

The top sailors are sponsored by sail manufacturers and don't usually have the option of choosing another brand. If they are in the top three of the PWA, they probably could go to the company of their choice and possibly get sponsored ($ and equipment), assuming the company hadn't spent their budget. If you are in the top 20, you probably could get any sail you want, but the $ (pay) may be a different story. All of this is just speculation, but I bet I am not far off.

Unregistered
25th July 2009, 03:29 AM
Wasn`t original question asking why Antoine is faster !!???
He`sbigger and better than others !!!!

Heavier sailors must have less drag (relatively).

Your top speed is when drag and power are equal ???? (but opposed)

If not why else are heavier sailors (generally) faster ????

Unregistered
25th July 2009, 11:01 AM
well changing board sponsers has made no difference to his speed.

Unregistered
25th July 2009, 11:07 AM
I modified my 6.2m race sail by reducing the clew(like the NP EVO11) by about 20cm and it has definelty made a big difference in the handling of the sail it's extra ability to exhaust the ultra strong gusts while maintaining easy handling.Didn;t lose no low end power and jbing has become a dream.Thumbs up for compact clew!

Unregistered
25th July 2009, 08:08 PM
I modified my 6.2m race sail by reducing the clew(like the NP EVO11) by about 20cm and it has definelty made a big difference in the handling of the sail

Can you open a new thread with some photos ?
There is also peterman.dk with something similar.

Deja Vu
25th July 2009, 09:54 PM
well changing board sponsers has made no difference to his speed.

That's debatable. He seems to be winning more decisively than ever now. There are obviously three or four board brands that are very competitive. I wonder how his results will affect JP sales - it sure won't hurt! It won't hurt JP's test results either since knowing its a winning board will make some positive impression on the testers (which may have been the case previously with SB). Why else pay someone "big" money to sail your equipment unless it translates into better sales? AA certainly seems to be earning his keep.

Unregistered
26th July 2009, 08:49 AM
Can you open a new thread with some photos ?
There is also peterman.dk with something similar.

sorry can't post pics here:

Deja Vu
29th July 2009, 05:37 AM
According to the most recent slalom news BD is back with F2??? If not, then we know how much proof reading the reporters do - none!

Unregistered
29th July 2009, 06:03 PM
antoine, dunky, josh, kevin & co in fuerte:

-> http://www.youtube.com/watch?v=6L2K_cEqsTc&feature=player_embedded

:-) chris

WindSurfingMag
30th July 2009, 10:11 AM
I'll dig up that article from Jim Drake, as well as the one from 1988. The one from '88 I'll only be able to scan, but hopefully I can get a PDF of the Drake article. Can't remember if that was '06 or '07... shouldn't be too hard to find.

And WOW, I couldn't believe Antoine pouring on the speed in that video of Heat 10 from two days ago. Jeez-o-man, that was awesome.

Deja Vu
31st July 2009, 12:46 AM
The article I referred to in the April 1988 issue of Windrider Magazine was actually written by Greg Aguera (Alex's brother) and not Alex Aguera! Definitely worth a read.

I've watched the PWA videos of the last few slalom races and all I can say is Wow! What an incredible battle out there on the water - these guys are awesome!

WindSurfingMag
31st July 2009, 03:14 AM
Here are the two articles, as well one additional article from Jim Drake that I ran across while looking for the first.

The first five links are the Greg Aguera article.

2nd two Jim's "Size matters" article

Last one a cool article on concept boards Jim has worked on.

http://www.windsurfingmag.com/article.jsp?ID=1000075027


Cheers,

JS

Kelvin
31st July 2009, 11:38 AM
The reason for NP racing success is simple . The NP sail luff is very very high tensioned - that's why the mast break so easily . The sail is very light . I suspect that they change ALL the battern to full carbon battern . So the sail is very fast .
But please don't think about buying one unless you are sponsored by NP and can have them
free . Otherwise you have to prepare to pay a lot of money on equipment breakage

Kelvin
31st July 2009, 03:56 PM
Forget to mention the super super high pressure of the cam on the mast that promise to cut a deep groove on the mast progressively until it break at the weakened site !

Deja Vu
31st July 2009, 09:50 PM
Here are the two articles, as well one additional article from Jim Drake that I ran across while looking for the first.

The first five links are the Greg Aguera article.

2nd two Jim's "Size matters" article

Last one a cool article on concept boards Jim has worked on.

http://www.windsurfingmag.com/article.jsp?ID=1000075027


Cheers,

JS

Thanks for this - great read! Nice to see the Robby Naish interview included alongside the JD article.

Deja Vu
3rd August 2009, 12:25 AM
Check out the JP website (slalom boards). AA and JP are rubbing a little salt into Starboard's open wound - not very neighbourly!

Unregistered
12th August 2009, 02:06 AM
Hey, most of sailors are on waist harnesses, BD, Finian, KP, Micah, but Antoine uses a seat harness! So he is the fastest, easy!

Deja Vu
15th August 2009, 10:45 PM
The big guys seem to be dominating right now - AA, FM & BD. With all other things being equal it seems to me that size and strength do matter a lot.