New GPS Team challenge category

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FormulaNova said..

I need to dream up a category I could win. What about for the person that talks the most on Seabreeze?

I think Mark Australia has a good head start there!

How about another category -

the Snake Move

Instead of being bored and crossing the 500m distance and gybing - start to improvise, and instead of straight cut through a chop cut a nice regular semi turns using, as a guidance, incoming chop waves.

I think such style could be easy developed into quite fascinating Olympic competition

GPS could measure the total number of snakes

Hey Macro,can't resist bringing up my idea for the 7th category of speed I have brought up before- Knots/kg

www.seabreeze.com.au/forums/Windsurfing/Gps/7th-measurement-category-for-GPSTC-knotskg/?page=1

It'll be hard to get approval to fiddle with what's been a brilliant idea Macro. My past idea, which fell flat, was a category for "latitude racing". Best time between the even minutes of latitude. A nautical mile if you can go directly north south, a bit longer if the breeze is not quite right. I thought it should appeal to the mathematically inclined geek because of its cartographical elegance. Not completely original borrows, a bit from that other GPS challenge

www.confluence.org/

Maybe we could include the confluences over ocean, the ones currently excluded from this competition?

Maybe suggest having a demonstration category each year, like the Olympics. If there's uproar about losing it at the end of a year, keep it in?

(I think I recall that a couple of blokes on Wallys were first to bag the confluence in one of the Great Lakes)
(edit again, no looks like they've now excluded inland waters www.confluence.org/country.php?id=3&showmap=true )

It's a fascinating site, I've just revisited it, ocean confluences within view of land are included. Here's one not yet bagged, the last one in NSW!
www.confluence.org/confluence.php?lat=-37&lon=150

Your statement about power to weight ratio favoring lighter windsurfers is completely contrary to the overwhelming evidence when it comes to speed sailing. Come to think of it, it is even more contrary to the World Cup Slalom results where tall, heavy (and very skilled and fit) guys dominate.

In the absence of the really strong winds at Luderitz this year during the Pro weeks, the taller, heavier guys still dominated.

In fact, there was a certain sub-6ft, sub 80 KG young French lad that comprehensively out-sped a lot of much larger guys on the very windiest day while I was there. I might add on a day when I was very hesitant to make runs during the peak of the wind! (Gusting 50-60Kts)

www.gps-speedsurfing.com/default.aspx?mnu=user&val=135649&uid=5203

That suggests that the smaller guys with lots of skill, confidence and experience (and extremely well tuned gear for their size) can do relatively better in the very strongest winds!

BTW. I calculate my speed to weight ratio after Luderitz is now 0.623. Gautier is on 0.642!!!

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Macroscien said..

sailquik said..

Your statement about power to weight ratio favoring lighter windsurfers is completely contrary to the overwhelming evidence when it comes to speed sailing.

I hope you had exciting and successful trip, congratulation.
But for convenience of speed sailing we are not going to re-write physics law here.
Doesn't matter - windsurfer, motor bike, drag car, jet plane or rocket ...

if the engine is stronger and mass smaller your ratio increase

what you do with this power and if you are able to control/ handle it that completely different story

now you could post as many red fingers again as you want

... I could propose next competition measuring G forces in windsurfing ( acceleration ratio) ... but that is already more that anybody here could handle...
bye

Thanks! I had an absolute ball!! (Between brief moments of wide-eyed terror! )

I think you are missing the point as it applies to windsurfers: Taller and heavier actually means more power to weight ratio! The reason is because of leverage. The laws of physics are quite clear on that. BTW, this does not seem to apply at all in Kitesurfing speed where there is no leverage advantage and some of the very fastest guys are quite average in height and weight.

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sailquik said..

Taller and heavier actually means more power to weight ratio! The reason is because of leverage. The laws of physics are quite clear on that.

This is actually quite interesting/ intriguing topic that could be resolved in the cold , civilized manner .

Power ratio of smaller guy vs. heavier windsurfer (?)

But obviously not for me to participate Doesn't matter if I could come with right mathematical formula or false , both will be spitted in red...

ha, its alright macro, i wouldn't take any of the forums to heart, its just a website thread,,,,in my experience, your wrong about weight, there is no advantage being lighter in any wind strength in regards to slalom sailing/speed sailing, sure there is plenty of great lighter sailors, but they would be better, faster, if they were heavier. It is weird how upset or offended people get by suggesting a new category. the hr and alpha category are great, there is definitely merit for a weight ratio handicap, personally, i could enjoy another alpha category, one where you can bear off, carve, and then bear off again on the exit run, basically not needing to get within 50m of starting point, since the 500m is the offical distance, it would make sense to have that category, the gpstc fundamentally is only concerned with speed, performance, so maybe a more recreational based category would be good for some. The format as it is, is fine, challenging, if anything was to change, it wouldn't really matter, people will adapt to the new challenges, and focus on them as they do the current challenges. Ha, i dont agree with macros ideas, but good on ya for sharing man, you seem very enthusiastic about your sailing, good luck

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Macroscien said..

sailquik said..

Taller and heavier actually means more power to weight ratio! The reason is because of leverage. The laws of physics are quite clear on that.

This is actually quite interesting/ intriguing topic that could be resolved in the cold , civilized manner .

Power ratio of smaller guy vs. heavier windsurfer (?)

But obviously not for me to participate Doesn't matter if I could come with right mathematical formula or false , both will be spitted in red...

Don't worry about red thumbs Macro, non-thinkers don't understand thinkers. (Maybe seabreeze should have a red thumb trading scheme, you get allocated 50 when you sign up and unless you collect them you run out?)

I disagree Sailquick, the physics is not clear. Sail design being similar across sizes we must first assume that for a given wind there's an optimum sheeting angle for best sail lift to drag. ie. the lift generated by the optimally sized sail, in the hands of a skillful rider, is proportional to the sail size. ( this may not be true, but it's a good place to start)

The drag of a hull though the water should, at first estimate, be proportional to the weight it's carrying.

If you look at the righting moment of the sail vs. the righting moment of a rider you find that as the rider's weight and height go up the relative sized sail that can be counter balanced falls behind. This is because the sail size increases with the square of dimension. So as sail size increases the centre of effort goes up with the square root of sail size. Total righting moment of the sail goes up with the sail area to power of 1.5

This must be balanced by the increased righting moment of the heavier rider. But his dimensions only go up with the cube root of weight.

So total righting moment of the rider is going up with his weight to the power of only 1.33.

It's pretty clear by the physics that for a given wind strength, sail size cannot increase linearly with rider mass. This is pretty clear on the water, you can often find someone half your weight sailing a 4.0 when your maxed out on a 6.0.

So what's going on? Do lighter sailors not sheet in efficiently? Are boards not constant with their drag vs. weight carried? Are sails not constant lift to drag through the sizes?

One thing that does clearly favour heavier riders is the parasitic drag of their bodies. Cross sectional area only going up with mass to the power of 2/3. Heavier sailors can also smash though chop without getting bounced around as much.

Not simple, but the leverage factor weighs against heavier sailors due to the fact that a double weight sailor can't hold down a double sized sail.

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Macroscien said..

..................

If the same proposal come Kato or Brad you will be screaming in the joy of pleasure.

....

Mmmm, let me think ...... mmmmm ..... nope.

If anyone (let alone Kato or Brad) suggested counting the number of gybes made is measured with a GPS I would assume they had recently hit the sand at 40 knots without a helmet

ha, if your gunna get crazy about it, well, you could just simply have outhaul, downhaul automated, and fin, all three constantly changing depending on force being measured by sail, and board deck, you could even have a sliding weight within in the board that moves up or down the board to help with accleration, ha, adjusting outhaul makes a good difference while sailing, i guess you could have that now done with a motor and you just press up, down button on boom to inch it mechanically,,,, or just go sailing and keep working on taking ownership of the many subtle factors that separate sailors ability, overall the sport is simple, to windsurf is simple, but to be a great sailor, well that is the result of years of mastering and building on many subtle factors, ha, the better i get at gyping, the more subtles just keep on appearing, im working through about twenty different little things that have been developed over time on the water, to do what is a simple move, the gype, ha, windsurfing is awesome, personally, i hope it just sorta stays the way it is, ha, ive got about another million things to figure out yet, good luck all

When will the magical 53.99 knots (100 km/h) be broken. Maybe next year& A A. Will probably break it.

I thick height & weight is only useful if you know how to use it.look at showboat (chris) hes one of the fastest sailors in the world pound for pound lets face it hes not exactly A.A. but lthink hes got the technique happening

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KevinD002 said..


How does one measure this speed to weight ratio?

Your top speed in knots divided by your weight in kg
eg. I have done 37.35 knots and I weigh 64kg
so 37.35 divided by 64 =0.583

The higher the number the better your skill

The holy grail of speedsurfing would be a 1.0 - 1 knot for every 1kg

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sailquik said..


BTW. I calculate my speed to weight ratio after Luderitz is now 0.623. Gautier is on 0.642!!!

So I would have to beat 39.8 knots to be a better sailor than you.

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Macroscien said..

KA360 said..

KevinD002 said..


How does one measure this speed to weight ratio?

Your top speed in knots divided by your weight in kg
eg. I have done 37.35 knots and I weigh 64kg
so 37.35 divided by 64 =0.583

The higher the number the better your skill

The holy grail of speedsurfing would be a 1.0 - 1 knot for every 1kg

sailquik said..


BTW. I calculate my speed to weight ratio after Luderitz is now 0.623. Gautier is on 0.642!!!

So I would have to beat 39.8 knots to be a better sailor than you.

Holly **** !! If that mean I need to hit 85 ktn ?? With my score 0.36 I have a lot of room for improvement
Even if that technically possible one may needs a lot of gutts to do so...

If speed riders have special harness lines to disconnect in the case of accident ? I can't imagine catapult at 50 ktn

For me the words of Everybody's Free (to Wear Sunscreen) apply to the idea of a speed per weight rating:
"Sometimes you're ahead, sometimes you're behind
The race is long and in the end, it's only with yourself"

Read more: Baz Luhrmann - Everybody's Free (to Wear Sunscreen) Lyrics | MetroLyrics