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  1. #1
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    Duckdiving/'low pressure zones"

    So when I was a young feller I stumbled upon this diagram by Mike Stewart. He was basically talking about the impact zone and broke it down into primary/secondary/etc, and also how there were low pressure zones right before the impact areas. I believe these low pressure zones exist, and sometimes I find myself there and diving with absolutely no resistance. Most recent experience was in the initial zone just inside of the lip's initial impact. Thought I was gonna get crunched but I popped through like a shart from a huffer.

    Open up the image and look at the digram at the bottom(text not as important this was the only one I could find)...have you fellers ever found these zones? Discuss...

    MS duck.jpg

  2. #2
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    any chance at a more legible image?

  3. #3
    Yep. Too small.

  4. #4
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    Here is some of the article form another site:

    HOW TO SIT ON YOUR BOARD IN THE IMPACT ZONE!

    Low pressures, locating, and then using low pressures in the white water. They are formed by the way hollow waves break. This is how they work: As a hollow wave rushes towards the beach and the lip throws out, it has a lot of inertia, not only because it is hollow but the entire wave including the lip is moving inward. As the lip lands and impales the wave face it plows down and forward anything it comes in contact with; An occasional fish, a tourist, the unknowing bodyboarder and what's important for this article water. Inside the barrel, as the lip lands, a shockwave is created and directly behind the shockwave, closer to the lip, a trench is formed by the boring lip. On the outside of the tube, the lip plows the water forward and up. As it bounces up and over it creates a pocket of virtually unaffected water. A low pressure zone in the chaos of white-water. As you are paddling out and you watch a hollow wave break directly in front of you, you can watch the lip boring it's way through the surface and then exploding upward and outward towards you. The area in front of the landing lip is the low pressure zone. The size of the low pressure pocket is directly related to 1. Scale, or the size of the wave and 2. How hollow it is. The bigger the wave the bigger the explosion and the bigger the low pressure area. I can recall a bodysurfing session I had at maxed out pipe where one of the biggest hollowest waves I have ever encountered broke top to bottom about 15 meters in front of me. Like an ostrich I just stuck my head under and waited for the inevitable, not knowing if the low pressure theory applied to 15 foot closeouts. To my pleasant discovery the wave gouged out a deep column of ocean the size of an olympic swimming pool that was virtually undisturbed and I simply floated to the surface feeling guilty for my lack of punishment. Needless to say it was the biggest low pressure i have ever been in. The hollowness of the wave effects the trajectory of the exploding water and thus how far in front of where the lip lands the low pressure will occupy. The hollower the wave the more water and power the lip has, the further the lip pitches out, and the larger the low pressure. Hollowness also effects how well-defined the low pressure pocket is. Once in really cavernous shore-break surf, I watched a thick lip slam in front of me and I simply sat up on my board like I was waiting for a set. The lip exploded up and over my head creating a giant white water bubble, totally avoiding the impact and still seated on my board, I simply popped up like nothing happened. An easy way to understand how low pressures work is to visualize a bouncing ball. The harder you throw the ball the further it will bounce (the bigger the low pressure). Also the angle you throw the ball effects the area between bounces. Where the ball hits the ground is equivalent to the impact zones, where the ball bounces up are where the low pressure zones lie. And just as a ball bounces more than once so does the lip. It is possible to find, although not as easily, the secondary and third low pressures. Each low pressure becoming less defined and harder to find the further away from the initial impact it is. So now that you know they exist, with some practice, you to can sit on your board in the impact zone with the confidence of not getting annihilated (most of the time). (Copied and pasted from the 805bbr bodyboarding forum.)


    PS Little $ Tbagger that is how you copy and paste, you use a foot note douche boy.

  5. #5
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    Fark when I open it on this computer it's larger...how do you enlarge pics on posts?

  6. #6
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    I have found myself in a "void" zone in duckdives. It's like finding a nug you forgot about. Best feeling ever!

  7. #7
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    Quote Originally Posted by seldom seen View Post
    Fark when I open it on this computer it's larger...how do you enlarge pics on posts?
    You have to make the pic size bigger pefore posting but that will distort the image more.

  8. #8
    Quote Originally Posted by seldom seen View Post
    So when I was a young feller I stumbled upon this diagram by Mike Stewart. He was basically talking about the impact zone and broke it down into primary/secondary/etc, and also how there were low pressure zones right before the impact areas. I believe these low pressure zones exist, and sometimes I find myself there and diving with absolutely no resistance. Most recent experience was in the initial zone just inside of the lip's initial impact. Thought I was gonna get crunched but I popped through like a shart from a huffer.

    Open up the image and look at the digram at the bottom(text not as important this was the only one I could find)...have you fellers ever found these zones? Discuss...

    MS duck.jpg
    I see a bodyboard. That invalidates everything.

  9. #9
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    can you give us a link to the image? (or put it in your gallery and link to that)

  10. #10
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    This is where I pulled it from, started searching for it yesterday and ended up here, definitely a more readable size...

    http://jamboards.com/view_topic.php?id=14532&forum_id=1