Ever seen a ski jumper go HIGHER than the starting point? I’ve done unintentional ‘‘airs’’ at Sunset, that shot me close to, if not, thirty feet in the air!
TWICE the height of the wave. My ‘‘yardstick’’ for that claim, is that I’ve done dives in the 25/30 foot range from the cliffs in La Jolla. The energy to do that came from SOMEWHERE, and not from me. Where is the nearest source of energy, that can be drawn upon? Oh, look! A big wave, moving very fast toward shore, with water moving BRISKLY up the wave face. You know, I’ll just bet THAT’S WHERE that extra energy is coming from. You think?
Oh, look! A big wave, moving very fast toward shore, with water moving BRISKLY up the wave face. You know, I'll just bet THAT'S WHERE that extra energy is coming from. You think?
The water moving up the face is some of it, but you’re also using the momentum you gained (from gravity) on the drop down, and of course the force of the wave itself pushing you in the vertical direction as it wells up.
None of us are saying that the water moving back towards the wave should be ignored. We’re just really puzzled by why you all don’t acknowledge the role of gravity and the vertical lifting force of the wave itself.
You have no idea what causes boosting air on a skateboard! Have you ever skated a pool? Or anything? Boosted air on one, perhaps? Can you say “Theory?” BIG HINT? What do you suppose causes this kind of thing right here? http://www.youtube.com/watch?v=J_55qvPsyVQ&feature=related
And you come on with the obnoxious bit again like everyone not agreeing with you is a nincompoop? You have the world’s biggest theory going there and that’s it!
You say you accidentally boosted airs 30 feet over the top of the wave crest at Sunset? I have to laugh! That’s just funny. Do you know how tall that is? Better yet, how fast was the wave propagating toward shore? And thus how fast was the crest moving toward you, and how fast did it pass under you? Don’t know? Oh well! That’s about it for that theory.
You guys are the ones with the funny quantum thing going on, not us! Gravity is pretty damned basic, and yet you guys act like we’re blind as bats!! That is f’ing hilarious! You’re claiming to have this esoteric understanding of something other than the utterly obvious gravitational acceleration and planing deflection and the simplest phenomena of a wave rolling toward shore giving you the ability to ride down the line and turn up and down! It’s relative perception, boys, and you’re outsmarting yourselves! LOL! Renewing grade. Gravity. Simple. Prove otherwise. You have theory and opinions. I can watch video and see, as plain as day, gravitational acceleration. Proof. Provide! Otherwise, stand down, and admit the beautiful universal power of simple, pure gravity driving the ride. LOL
Thrailkill is right. I saw the tony Hawk junior high 101 physics video. Tony Hawk
did one small push in a huge halfpipe. His squat (as in what you know) to full stance pumping action allowed gravity to use his weight to make Tony go faster and higher with each timed pump. Of course the work involved in the final result was done by the human squat to stance pumping action.
Unfortunately to try to simplify surfing to static anything is eventually futile.
Maybe if you mental masturbators ever surfed a face over 40 feet you could understand what Thrailkill is saying. I love getting big air instead of the plain old kickout. I easily can believe the 30 ft story and even with a twist and flip.
Nobody gives a flying half turd what you say about anything, you know. You’re nobody and you’re nothing. Just some wanker who likes Surftechs, who shows up on the backyard-surfboard-building site for some reason every now and again… why? Nobody knows or cares. I would say you’re the masturbator but you don’t even have the entertainment value of a good wank.
No, not theory, hands on experience in waves you have no experience with, or understanding of. And yes, quite by accident, when I thought I was going to glide up and out of a saddle, on a 15’ wave at Sunset, I got shot into the air (due to the very high rate of speed) to a height I was quite familiar with, as a diver. The rest of the story, not mentioned, is that my board, on the same trajectory as me, glided in under me and I put my chin through four layers of 10 oz cloth on the rail, when I came down . The result of that was several hours of ‘‘lost time’’ amnesia. Don’t get your panties in such a wad, eh. You want a laugh, read your post about a ski jump. Yes, gravity is always there, but it is not the major force allowing a rider to surf ‘‘down the line’’. As to skateboards, yes, been there done that. Before it was fashionable, before clay wheels, before neoprene wheels, before manufactured boards. We made our own, with steel wheels. I lost interest in skateboards once I got a taste of quality surf. But I digress. Is this not a thread about forces on a SURFBOARD? Lets keep it there. You are making statements about a level of surfing that you have not experienced, and don’t understand. Be as smug as you want, but you are still wrong in your perception. Your hostility disappoints me. 32 feet pr sec/sec (gravity) is a contributor to board speed, no doubt, but it is NOT the only, or the most significant contributor. You need to experience dropping straight down a very large wave, accellerated by gravity, and not be able to reach the bottom, and get drawn up to the lip and pitched. Ooops, what happened? How can something like that be avoided? What force can you tap to enable you to make the same wave? I’ll leave it for you to speculate, I already know. The information is IN THIS THREAD, you need only tease it out.
To everyone, please try not to get personal, you will regret it when you re-read your comments in the archive in 6 months time.
Anyway… I don’t have a problem believing Bills claim (or theory). If you watch big wave surfers, particularly at Teahupoo, you will often see them catch a rail, and though gravity is still at play, they still get sucked right up the face and spat out, hell even jetski’s get sucked up the face.
No if a guy is on a board already heading up a face and the fins and rail catch the flow of such an almost pitching wave I can well believe that you can be pitched well beyond wave height.
It has happened to me in head high lumpy(onshore) days with a good shorebreak. One time I remember on a 6’2" Thruster I went to kick out and I unintentionally got launched and I kept going up, I distinctly remember thinking “ok I should be falling now, but I kept on going up, then thinking again definitely should be falling now” on that occasion i launched higher than the waves height"
Sorry no numbers, just intuition combined with being sympathetically in touch with experience.
You just have no grasp, concept, or understanding, of the speeds, or power involved in island size 15 foot surf. I know what occurred. It was not anticipated, and I wish it had not happened. It put me out of commission for several days, and it hurt. Things that you have not experienced, may be difficult for you to believe. I’m estimating the height, based on other experiences, and the long time it took to come down. I’ve gone off the high point at Waimea Falls. We all thought the high point was 75 feet. It later proved to be 55 feet. (measured by Diff) Point is, the distance to the water didn’t look any different, than looking down from that platform. I was a long way up in the air! Gravity didn’t put me up there, but it sure got me down.
BIll, the wave is not fixed in place. It is constantly moving towards that water that you picture as flowing out to sea. The net movement of that water you see as flowing towards sea is basically zero, and even worse, more towards land than to sea.
Everyone has felt, and agrees, that a little water gets sucked out towards sea by an incoming wave. However, there is also the wave itself pushing up from the bottom that must be considered if we’re talking about forces that push the surfer up above sea level.
The wave is coming in, its front begins to hit something shallower and be slowed down, the part of the wave behind this leading edge hits this slowing part of the wave and has no where to go but up. I say it is mainly this that lifts the surfer up above sea level. The surfer can position himself in various ways to take advantage of the gravity that wishes to return the surfer to sea level: he can drop down the face, or he can proceed at an angle where the lifting of the wave and gravity balance each other out and he will surf down the line in perfect trim since the wave is coming in at the exact same angle the surfer trims at (i.e. waves break down the line, not straight to shore, so there is no need to talk about “horizontal” surfing that is perpendicular to wave energy since the surfer is actually always keeping that energy behind him and being pushed/supported by it when he’s in trim). Refer to my yardstick example.
Am I correct in saying that you believe the surfer is lifted up by the force of water that is coming at him from shore out to sea? I see him being lifted up by the force of the wave coming towards shore which lifts a bunch of water basically straight up.
For the record: ‘‘I do not picture water flowing out to sea.’’ There IS a net zero movement of the water, ONLY IN AN UNBROKEN WAVE. Once the wave breaks, there is a net flow to the beach. That is the reason rip currents form, and FINALLY, you do get a flow out to sea. I’m sorry that you can’t, or won’t, connect the dots here. The information is all within this thread, with the full picture, a function of the information provided by several posters, you among them. You have part, but not all, of the pieces. But they’re there for you to grasp. (the pieces) I can’t help you see it, if you are blind to it. I’m not trying to be disrespectful to you in any way. I’m surprised that there is such a widely held misunderstanding of the interaction of board and wave, and how a surfboard functions, on a wave.
What you are riding is a slope. As you ride down the face of a 20 or 30 foot face, you are riding a slope that is progressing toward shore at 18 or 20 miles per hour or so, yes?
You accelerate down that face using gravitational rate of acceleration, yes? So you end up going a few mph faster even than the wave is moving toward shore…
So you get out ahead of the wave to the flats at what, 25 or 30 miles an hour?
You bleed off a few mph in making your bottom turn, and now you and your board are moving over the water at 25 mph or so, yes? Say 23 mph as you turn back toward the face…
So you turn back toward the face which is a ramp moving toward you at the same rate of speed as before, 18 or 20 mph, and now that combines with your over-water speed coming toward it to produce a relative speed of you moving toward the crest at 35 or 40 mph…
So you make the climb up this 20 or 25 foot tall curved ramp at 30 mph or so, and you’re surprised when you go airborne,
and you ascribe it to something other than the gravitational acceleration you built up on the way down
combining with the crest’s (ramp’s) speed toward you as a combined speed?
And you think we’re missing the forest for the trees?
What you are riding is a slope. As you ride down the face of a 20 or 30 foot face, you are riding a slope that is progressing toward shore at 18 or 20 miles per hour or so, yes?
You accelerate down that face using gravitational rate of acceleration, yes? So you end up going a few mph faster even than the wave is moving toward shore…
So you get out ahead of the wave to the flats at what, 25 or 30 miles an hour?
You bleed off a few mph in making your bottom turn, and now you and your board are moving over the water at 25 mph or so, yes? Say 23 mph as you turn back toward the face…
So you turn back toward the face which is a ramp moving toward you at the same rate of speed as before, 18 or 20 mph, and now that combines with your over-water speed coming toward it to produce a relative speed of you moving toward the crest at 35 or 40 mph…
So you make the climb up this 20 or 25 foot tall curved ramp at 30 mph or so, and you’re surprised when you go airborne,
and you ascribe it to something other than the gravitational acceleration you built up on the way down
combining with the crest’s (ramp’s) speed toward you as a combined speed?
And you think we’re missing the forest for the trees?
I don’t see how the water moving up the wave face could be traveling slower than the waves forward progression toward shore.
The water is moving up the wave face because the wave is moving toward shore. The water speed is a function of the wave speed.
You are right that the surfer gains velocity from moving down the slope (gravity), and the surfer gains velocity from the wave moving toward shore, but the surfer also gains velocity, especially when projecting out of a bottom turn and placing the maximum fin and bottom area in the direction of the flow, from the movement of the water up the wave.
The wave is coming in, its front begins to hit something shallower and be slowed down, the part of the wave behind this leading edge hits this slowing part of the wave and has no where to go but up. I say it is mainly this that lifts the surfer up above sea level. The surfer can position himself in various ways to take advantage of the gravity that wishes to return the surfer to sea level: he can drop down the face, or he can proceed at an angle where the lifting of the wave and gravity balance each other out and he will surf down the line in perfect trim since the wave is coming in at the exact same angle the surfer trims at (i.e. waves break down the line, not straight to shore, so there is no need to talk about “horizontal” surfing that is perpendicular to wave energy since the surfer is actually always keeping that energy behind him and being pushed/supported by it when he’s in trim).
I think that this is a good description of what is happening.
Don’t overlook the deceleration due to gravity, as soon as the rider turns up the wave. Axiom: ‘‘What gravity giveth, gravity taketh away.’’ So, where does the ‘‘extra’’ speed come from? Don’t forget, the shoaling of the base of the wave, accelerates the water up the face of the wave. The water movement at the base of the wave, is slower that the water movement near the crest. It’s a relative thing. In effect, the ‘‘ramp’’ is slowing down. At least the bottom is. A point to consider, is that a board accelerates through, and out of the first turn, after the drop. On cutbacks you’ll bleed off speed.
I didn’t say it was moving slower, but if it’s the same speed, the grade is the thing.
If the upward movement of the water is just a function of the crest moving forward, that’s not a “flow” that is separate from the ramp moving forward, which is what some are starting to come clean about alleging, with some of the comments about current.
The crest is moving forward and the water is moving upward as the wave pulse passes through the water. Riding the surface of this big bump is just that, just as a carpet would pass over a roller.
If the throwing lip or the lip jacking forward over vert as a function of shoaling is what Bill is talking about, that’s a different thing than the overall thing we had been talking about too.
In all cases, if you turn toward the crest, you are combining your forward planing speed with the wave’s propagation speed toward shore. This combination of velocities is what’s giving the illusion of this “flow” (edit: and the upward gain of the slope) contributing all this lift. It’s hard to believe that the combined velocities of your planing speed and the crest’s toward shore could be ignored, and the forward-moving ramp aspect, but it is and has been, if you read the comments.
BTW if anyone wants to review the “dynamic flow” of the posts on this thread, you will all note that the snideness and ridicule and sarcasm started with … well, not Rich and I. In my experience, the first instance of ridicule or sarcasm usually flows from the ones with the weakest argument. Almost always. This is something I have much firsthand experience and much eyewitness experience of here. To borrow a phrase, The evidence is in this thead–all you have to do is read it carefully. Spot the hippity-hop arguments from this to that part of the act of surfing, the assertions of private knowledge that you must drink this or that KoolAid to grasp, and the assertions of “you can’t possibly understand” this fundamental physical dynamic of surfing, because you’ve never surfed in Hawaii…
If the upward movement of the water is just a function of the crest moving forward, that’s not a “flow” that is separate from the ramp moving forward, which is what some are starting to come clean about alleging, with some of the comments about current.
The crest is moving forward and the water is moving upward as the wave pulse passes through the water. Riding the surface of this big bump is just that, just as a carpet would pass over a roller.
It is flow relative to the surfboard. The water is moving relative to the surfboard.