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uk_exile

skiing acceleration, pull forces etc ?

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uk_exile

I'm always trying to explain to people just what a buzz a slalom ski gives. The power, acceleration & speed but it's difficult to give numbers that are real. They just think oh yeah, easy as standing there getting towed along and just leaning a bit. No comprehension of the physical forces involved. I'm expecting real acceleration numbers are quicker than the quickest sports cars or bikes.

Does anyone have any numbers for slalom runs?

Accelerate from 25kph to 100kph & slow to 25kph 6 times cycle in 16 seconds ?

Max pull is x times body weight ?

G force is xG ?

I like wakeboarding too but maybe this would once & for all explain which is 'harder' :lol: Fully expect wakeboard falls accelerate a lot faster than ski falls though Surprised.gif

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jgouveia3

my sister's new boyfriend came skiing with us for the first time this week. he said he had been "skiing" all his life. He watched us ski a couple passes through the course, then he tried. his only comment was that was the first time in his 40 years of skiing that he had ever seen real skiing, he always thought the point was to ski fast in circles!

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aneal000
I like wakeboarding too but maybe this would once & for all explain which is 'harder' :lol: Fully expect wakeboard falls accelerate a lot faster than ski falls though Surprised.gif

Ah geesssee... here we go again!

Dude, all the math in the world isin't going to explain a left turn and a right turn. It's obvious to the "non boater" that wakeboarding is the better sport.

Simple test: Allow a "non boater" to watch 5 minutes of a pro level slalom skier and a pro level wakeboarder - see which one holds their interest.

Answer: After 16 seconds of slalom the "non boater" gets the idea. After 5 minutes of wakeboarding the "non boater" has only seen a fraction of the grace, style, and bag of tricks the pro wakeboarder has to offer.

;)

edit: after rereading I noticed you did say harder not better. I'll give you the fact that getting up on a slalom ski is harder but reality is the skier only has to learn 2 things - how to turn left and how to turn right. The rest is rythum, timing, and practice. Wakeboaring has thousands of various inverts, grabs, spins, and combinations of all three. I'll also give you the fact that both take a certian level of dedication to master, most people just get bored to death with slalom that's why you have less pro skiers now that a "better" sport has come along. :)

Edited by aneal000

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I like wakeboarding too but maybe this would once & for all explain which is 'harder' :lol: Fully expect wakeboard falls accelerate a lot faster than ski falls though Surprised.gif

Ah geesssee... here we go again!

Dude, all the math in the world isin't going to explain a left turn and a right turn. It's obvious to the "non boater" that wakeboarding is the better sport.

Simple test: Allow a "non boater" to watch 5 minutes of a pro level slalom skier and a pro level wakeboarder - see which one holds their interest.

Answer: After 16 seconds of slalom the "non boater" gets the idea. After 5 minutes of wakeboarding the "non boater" has only seen a fraction of the grace, style, and bag of tricks the pro wakeboarder has to offer.

;)

edit: after rereading I noticed you did say harder not better. I'll give you the fact that getting up on a slalom ski is harder but reality is the skier only has to learn 2 things - how to turn left and how to turn right. The rest is rythum, timing, and practice. Wakeboaring has thousands of various inverts, grabs, spins, and combinations of all three. I'll also give you the fact that both take a certian level of dedication to master, most people just get bored to death with slalom that's why you have less pro skiers now that a "better" sport has come along. :)

Ok I'll bite and I know I shouldn't because I believe you are just yanking a chain to see what happens next.

Well, do you feel better about yourself after saying that? Slalom does only go left turn right turn, you got us slalom skiers there. But wait, boarders only go left and right too! Oh, boarders can jump and do some kind of spins or they can grab different things whil ein the air but, aren't those just details of how boaders go "left turn and right turn"? And isn't rythem and timing the details of how well a slalom skier can do just like the details of how a boarder can do a 1050 or whatever the lastest boarder thing is to determine how well they can do?

It's all in the details.

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I'm always trying to explain to people just what a buzz a slalom ski gives. The power, acceleration & speed but it's difficult to give numbers that are real. They just think oh yeah, easy as standing there getting towed along and just leaning a bit. No comprehension of the physical forces involved. I'm expecting real acceleration numbers are quicker than the quickest sports cars or bikes.

Does anyone have any numbers for slalom runs?

Accelerate from 25kph to 100kph & slow to 25kph 6 times cycle in 16 seconds ?

Max pull is x times body weight ?

G force is xG ?

I like wakeboarding too but maybe this would once & for all explain which is 'harder' :lol: Fully expect wakeboard falls accelerate a lot faster than ski falls though Surprised.gif

The pull on a skiers body is about 4g's IE we experience about 4 times our body weight for brief periods of time. The last measurements I saw for slalom skiers was that Wade and some other elite skiers would reach top speeds of 59mph.

Hope this helps....

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HOskier313

Aritcle taken from Waterski Magazine - 6/4/2003

"I feel the need for speed.” Long before Goose muttered that famous line in the blockbuster movie Top Gun, water skiers have felt the need. There’s nothing quite like the electrifying sensation of zipping across the wakes at what feels like Mach one, is there? But skiing has a love/hate relationship with speed. It can be your best friend or worst enemy -- just ask Goose.

That’s why we asked five of the world’s best skiers to give us insight on how they view the battle for speed. We also clocked their speed measurements with a hand-held sports radar gun to find out just how fast they’re really moving across course. For the complete story and incredible photos, pick up the July 2003 WaterSki magazine. Included here is commentary from pro skier Wade Cox, plus a streaming video of Wade powering through some high-speed action.

Wade Cox

Shortline equals fastline

What I find most interesting after looking at my recorded gate speeds into one ball is that between 15 off and 35 off I was traveling at almost exactly the same speed. However, as soon as we shortened the line from 35 off to 38 off, my gate speed increased nearly 4 mph (from 49.7 mph to 55.2 mph respectively). This big jump made in speed made me wonder if that’s why so many amateur skiers run 35, but rarely learn to master 38 off.

In a perfect slalom world, the skier would want to achieve a 180-degree arc on the boat from one buoy to another. The key to reaching this 180-degree arc on the boat is obviously speed. The only real way to keep up with the slalom rope shortenings is to travel faster.

So how can you travel faster as the line gets shorter? Gate tempo is the key. Your gates will allow you to create maximum speed, which in turn will allow you to ski the best possible arc. By relaxing your legs you'll be able to get into a more athletic stance. This lowered position will allow you to create maximum leverage, which in turn produces a release. The better you release, the more run time you have out to the buoy, increasing your chances of skiing closer to that 180-degree arc.

Wade's Speeds

15 off – 49.8 mph

28 off – 49.3 mph

35 off – 49.7 mph

38 off – 53.5 mph

39½ off – 54.6 mph

41 off – 55.2 mph

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aneal000
Ok I'll bite and I know I shouldn't because I believe you are just yanking a chain to see what happens next.

Do I hear 11 pages?

ROFL.gif

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Ok I'll bite and I know I shouldn't because I believe you are just yanking a chain to see what happens next.

Do I hear 11 pages?

ROFL.gif

If this goes 11 pages doesn't that prove that slalom isn't dead? I think so - COME ON SLALOM SKIERS!!!!!

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Malibudude

Ok I'll bite and I know I shouldn't because I believe you are just yanking a chain to see what happens next.

Do I hear 11 pages?

ROFL.gif

Nope, the attention span of boarders is too short. ROFL.gif

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BlastRlxi

There isn't really any point in going 11 pages. We have already proven that there is no way we are going to get everyone to agree that slalom is the better or harder sport. Some people are just too hard headed. :)

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VinRLX

Can't we all just get along? :lol:

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ibelieve

Wakeboarding is like riding a jetski ... anyone can sit their fat a__ on a jet ski. Why do you think jetskis and wakeboarding are so popular ... anybody can do it and have fun.

Now, for slalom of footin, it takes hard work to prefect these sports.

It all has to do with the "I want it now generation". Instant success and fun without having to work for it!

Just my 2 cents ... and a chance to stir things up, but a little off topic!

:-)

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aneal000
Wade's Speeds

15 off – 49.8 mph

28 off – 49.3 mph

35 off – 49.7 mph

38 off – 53.5 mph

39½ off – 54.6 mph

41 off – 55.2 mph

So at 28 off, a good - he's a decent skier - number the pro is only going 27% faster than the boat?

I'm guessing the recrecrational skier might be slightly less due to their form. So maybe 25% faster than the boat. Oh, and most recrecrational skiers are at 34mph right? So maybe you 28 off skiers are at 43mph?

But how fast do wakeboarders fall out of the sky? Maybe not as fast as one would think!

We all know that 9.8 meters/second(squared) is the rate of accelleration due to gravity; or 21.936mph/second if you prefer. But lets convert that to something we can grasp.

If we were to fall for 1 second we would of started at 0mph and ended up at 21.936 so we must figure the average speed over 1 second is really 10.968mph. 10.968mph also equals 57,911.04 feet/hour and their are 3600 seconds/hour so we can easily divide the two to get the average feet/second during the first second - or 16.0864feet/second.

But do wakeboarders get 16 feet in the air or high enough to actually free fall for 1 second? Probably not. But doubleups, trippleups, and the wake of the new 247 could allow riders to get close! Let's say 10' is reslistic and I truly believe it is. So since acceleration is for the most part linear we can calculate 21.936/16x10= 13.71mph at impact from 10 feet.

I ride at 23.7mph and can reasonably assume I can achieve an additional 25% (propably around 40 on some tricks - I can rationalize this number if you would like) but lets keep it safe and say I can hit 29.625 (23.7x1.25). This is the speed in direction A or the speed the slalom skiers can achieve. But wakeboarders also have gravity which creates additional speed in direction B. Add both together and you get roughly 43.33 mph total speed upon impact. Humm... interesting number huh?

That proves it they are equal! Tongue.gif

Edited by aneal000

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SunriseH2OSkier

Man, has this been a slow summer on the board or what? Between the wakeboarders vs. slalom skiers and the 2.5 months to Hawaii and back topics, I'd swear we were in the middle of February around here.

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mrothwell

Wade's Speeds

15 off – 49.8 mph

28 off – 49.3 mph

35 off – 49.7 mph

38 off – 53.5 mph

39½ off – 54.6 mph

41 off – 55.2 mph

So at 28 off, a good - he's a decent skier - number the pro is only going 27% faster than the boat?

I'm guessing the recrecrational skier might be slightly less due to their form. So maybe 25% faster than the boat. Oh, and most recrecrational skiers are at 34mph right? So maybe you 28 off skiers are at 43mph?

But how fast do wakeboarders fall out of the sky? Maybe not as fast as one would think!

We all know that 9.8 meters/second(squared) is the rate of accelleration due to gravity; or 21.936mph/second if you prefer. But lets convert that to something we can grasp.

If we were to fall for 1 second we would of started at 0mph and ended up at 21.936 so we must figure the average speed over 1 second is really 10.968mph. 10.968mph also equals 57,911.04 feet/hour and their are 3600 seconds/hour so we can easily divide the two to get the average feet/second during the first second - or 16.0864feet/second.

But do wakeboarders get 16 feet in the air or high enough to actually free fall for 1 second? Probably not. But doubleups, trippleups, and the wake of the new 247 could allow riders to get close! Let's say 10' is reslistic and I truly believe it is. So since acceleration is for the most part linear we can calculate 21.936/16x10= 13.71mph at impact from 10 feet.

I ride at 23.7mph and can reasonably assume I can achieve an additional 25% (propably around 40 on some tricks - I can rationalize this number if you would like) but lets keep it safe and say I can hit 29.625 (23.7x1.25). This is the speed in direction A or the speed the slalom skiers can achieve. But wakeboarders also have gravity which creates additional speed in direction B. Add both together and you get roughly 43.33 mph total speed upon impact. Humm... interesting number huh?

That proves it they are equal! Tongue.gif

OK Tony, I know you know better, but since you are misleading, I'll dispel your math.

Since direction A and direction B are perpendicular to each other, you cant just add them together. In this case, it's the square root of A squared + B squared:

SQR(29.625*29.625 + 13.71*13.71) = 32.64mph OR slower than a rec skier just following the boat. Tongue.gifTongue.gifTongue.gif

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JustinOSU

Wade's Speeds

15 off – 49.8 mph

28 off – 49.3 mph

35 off – 49.7 mph

38 off – 53.5 mph

39½ off – 54.6 mph

41 off – 55.2 mph

So at 28 off, a good - he's a decent skier - number the pro is only going 27% faster than the boat?

I'm guessing the recrecrational skier might be slightly less due to their form. So maybe 25% faster than the boat. Oh, and most recrecrational skiers are at 34mph right? So maybe you 28 off skiers are at 43mph?

But how fast do wakeboarders fall out of the sky? Maybe not as fast as one would think!

We all know that 9.8 meters/second(squared) is the rate of accelleration due to gravity; or 21.936mph/second if you prefer. But lets convert that to something we can grasp.

If we were to fall for 1 second we would of started at 0mph and ended up at 21.936 so we must figure the average speed over 1 second is really 10.968mph. 10.968mph also equals 57,911.04 feet/hour and their are 3600 seconds/hour so we can easily divide the two to get the average feet/second during the first second - or 16.0864feet/second.

But do wakeboarders get 16 feet in the air or high enough to actually free fall for 1 second? Probably not. But doubleups, trippleups, and the wake of the new 247 could allow riders to get close! Let's say 10' is reslistic and I truly believe it is. So since acceleration is for the most part linear we can calculate 21.936/16x10= 13.71mph at impact from 10 feet.

I ride at 23.7mph and can reasonably assume I can achieve an additional 25% (propably around 40 on some tricks - I can rationalize this number if you would like) but lets keep it safe and say I can hit 29.625 (23.7x1.25). This is the speed in direction A or the speed the slalom skiers can achieve. But wakeboarders also have gravity which creates additional speed in direction B. Add both together and you get roughly 43.33 mph total speed upon impact. Humm... interesting number huh?

That proves it they are equal! Tongue.gif

OK Tony, I know you know better, but since you are misleading, I'll dispel your math.

Since direction A and direction B are perpendicular to each other, you cant just add them together. In this case, it's the square root of A squared + B squared:

SQR(29.625*29.625 + 13.71*13.71) = 32.64mph OR slower than a rec skier just following the boat. Tongue.gifTongue.gifTongue.gif

BORING!!! Lazy.gif

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aneal000
OK Tony, I know you know better, but since you are misleading, I'll dispel your math.

Since direction A and direction B are perpendicular to each other, you cant just add them together. In this case, it's the square root of A squared + B squared:

I'm surprised that is the only error you found... Tongue.gif

Edited by aneal000

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BillFooter

You're both a bunch of sissies. Us footers go 44-45 in a straight line!! How fast do you think we are going around a corner? Tongue.gif

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smooth as glass

Tony, there was some 'embellishment', there. The quote missing from Wades article was " Slalom is like driving an F1 racing car.!".... Now that's something to aspire to! I ski to live and live to ski. I must say however I love to watch my son do Sbends and whirlys. We have a respect for each others discipline, and ride together every chance we get.

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aneal000
Tony, there was some 'embellishment', there.

Yeah, you're right. I really shouldn't of used Wade Cox's numbers to represent all skiers... Tongue.gif

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gonorth
You're both a bunch of sissies. Us footers go 44-45 in a straight line!! How fast do you think we are going around a corner? Tongue.gif

And, you didn't use 6 pages of math formulas to make that point. Well stated! You win.

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mrothwell

OK Tony, I know you know better, but since you are misleading, I'll dispel your math.

Since direction A and direction B are perpendicular to each other, you cant just add them together. In this case, it's the square root of A squared + B squared:

I'm surprised that is the only error you found... Tongue.gif

It's not, just the most glaring.

You're both a bunch of sissies. Us footers go 44-45 in a straight line!! How fast do you think we are going around a corner? Tongue.gif

And, you didn't use 6 pages of math formulas to make that point. Well stated! You win.

Agreed

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aneal000

OK Tony, I know you know better, but since you are misleading, I'll dispel your math.

Since direction A and direction B are perpendicular to each other, you cant just add them together. In this case, it's the square root of A squared + B squared:

I'm surprised that is the only error you found... Tongue.gif

It's not, just the most glaring.

Ouch. Crazy.gif

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mrothwell

OK Tony, I know you know better, but since you are misleading, I'll dispel your math.

Since direction A and direction B are perpendicular to each other, you cant just add them together. In this case, it's the square root of A squared + B squared:

I'm surprised that is the only error you found... Tongue.gif

It's not, just the most glaring.

Ouch. Crazy.gif

Sorry, I forgot the: Tease2.gif

You did have a neato math problem. ROFL.gif

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aneal000
You did have a neato math problem. ROFL.gif

Well that makes it all worth while then. :blush:

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