Scent of Perfection

The Perfect Surfboard

The perfect surfboard is one matched or built for a specific rider, who optimizes performance on a particular wave. Surfboard perfection is like a beautiful fragrant flower blossom and is equally fragile. It wilts under the wrong conditions and blossoms under ideal conditions. Pros will carry a multitude of surfboards to the beach, choosing the one that best matches the current conditions with their preferences. Surfboards vary in length, width, thickness and shape. Most surfboard bottom shapes are flat, with board bottoms looking like bent lumber. A crude comparison for a flower, but after all, a surfboard is a board. Flatness defines a planning hull, because it defies water penetration with speed. A modern surfer's quiver will not include a semi-displacement shape. Semi-displacement shapes have possibilities for the future. A semi-displacement surfboard may improve performance. It may be a perfect flower in disguise.

Today more than ever before, gifted surfers are landing airborne maneuvers. This includes free fall drops, as well as flights launched off wave tops. Surfers have become skilled in flight. Landing success is more skill than luck. Weighted landing such as a tail first landing, have more opportunity for success. The reason being, the tail penetrates water with the riders weight. A weighted nose first landing is also a successful aerial maneuver. The rider moves his weight to the nose in flight. His weight breaks the water's surface on impact as he spins around in a reverse or forward flip.

The most difficult landing to complete is the hard forward flat landing or an unweighted nose landing. A surfboard suddenly stops with impact in these landings. The surfer is pitched forward or catapulted and continues through the air with his momentum or kinetic energy. His kinetic energy may be used instead, to drive a board with a different design. More on this follows later.

Movement suddenly stops when hydrodynamic pressure, or lift on the surfboard's flat bottom, blocks water penetration on high impact. This is Bernoulli's Principle. Water bonding force makes it impermeable creating a force or pressure that exceeds the force of the falling surfboard and rider. The board cannot penetrate water. Water will not part and the surfboard stops. This force is hydrodynamic lift. The same force that makes surfing possible, can stop a surfer. Water needs time to move out of the way of moving objects; known as transition time. When an object initially moves through water, it moves by moving water out of it's way, this is called displacement. At lower speed, water moves around moving objects and objects take water's former place. The dynamics change at high speed.

When you dive into water from low heights, water cushions your fall. Your body pushes water and your speed decelerates. The higher the dive, the higher your speed. When you high dive from two hundred feet you will move faster and hit water with more force. Water will not have time to move or transition. On impact, you make a little splash. This will not displace enough water to cushion your fall. Instead water blocks you and supports your body, so it momentarily stops on the surface. This happens a second before you decelerate and sink. Your body, not water, will absorb the impact causing you great pain, especially if you land flat. A flat surfboard in a flat landing or one landing on the nose rocker bend stops on the surface. The abrupt stop is identical to your painful body slam. The impact is tremendous. This is due again, to hydrodynamic force. Water bonds together and will not part for speeding objects. Water resists parting with speed due to intermolecular bonding of hydrogen atoms. In the following video Garrett McNamara hits water so hard he shatters his arm. The injury ends his big wave career.

Hydrodynamic lift that supports surfers on the water's surface is attained in stages. Initially a surfer starts a ride in the displacement stage, pushing water out of his way, as he paddles furiously for a wave. He generates both a forward and trailing wake. He pushes less and less water with speed. He transitions by gradually rising in the water and accelerating as the forward wake dissipates. A surfer begins planning like a speed boat with its nose up. The forward wake or forward drag disappears, when the surfer is completely supported hydrodynamically. Water supports him, as it cannot move out from under him due to speed. Aerial maneuvers have disrupted this sequence. Flying surfers go from planning phase to displacement phase without transition time. In a hard flat landing where water cannot move, a surfer needs to use weighted force or alternative bottom shapes to transition. Flat bottoms prevent penetration by maximizing lift. It also optimizes braking or stopping on high impact.

Abrupt stops and catapults can be reduced. Transition can succeed by using a semi-displacement hull shape in the nose underside. This is a Vee or round shaped bow which pushes water aside and out of the surfer's path. It also cushions landing by absorbing impact. This allows surfboards in a shallow dive to continue moving after high water impact, reducing catapults. Another way to reduce sudden deceleration, is to factor weight with rocker. A flat bottom will push water forward before directing it around the surfboard. This takes time and consumes energy and power known as gravity force. Weight and speed are factors of gravity force and can be calculated with an equation (Sp x Wt = GF). Speed is a variable and gravity force calculations therefore fluctuate. A heavier surfer using moderate nose rocker may ride out of a shallow nose poke at planning speed. This is because he can move more water out of the way with power generated by his weight and speed. A lighter surfer on a surfboard with the same nose rocker may be catapulted in a similar situation. The reverse, with success to the light surfer, can occur. Success depends on nose rocker and angle of attack. The solution is to balance rocker with weight.

A surfer must consider board weight, nose rocker and wave conditions to reduce wipe outs. A combination of reduced rocker and displacement shapes may optimize performance. All options have trade offs which may compromise performance, but; prevent a wipeout. There is a point of NO- recovery, which is attained when the nose plunges deep and vertically. Too much weight, too much speed, and too much rocker will cause disaster. Brazil's success in competition may reflect its attention to balancing weight to rocker.

John John breaks his fins free and drops weightlessly to the bottom.

He keeps the nose up and lands flat.

His surfboard stops moving, stuck after high impact with the wave botom.

The abrupt stop causes John John to fall forward.

A semi-displacement board is a dual function surfboard. It is both a displacing and planning board. Its nose pushes water out of the way at lower speeds. It planes on its aft half like a planning surfboard. Blake, Duke, Simmons, Kelvin and Quigg were the pioneers of Displacement surfboards. By the early sixties nearly all surfboards were shaped with belly. Belly disappeared with nose riding popularity. Concaves and flat bottom bottoms evolved on surfboards with wide points forward of center. These surfboards trimmed when weighted and ridden forward, supporting weight on the nose by maximizing lift. Over the years nose rocker increased and nose bottoms remained flat. High nose rocker and flat bottoms work, only if the bottom does not impact water at high speed. When a surfer loses control or free falls nose first, high impact on the nose rocker bend with flat under side, generates lift or resistance. This may push the surfboard backwards and catapult the rider.

Niccolo almost completes this ride in the following video. The flat bottom just catches slightly and launches him. He might have made this wave using a board with less nose rocker or on a displacing shaped nose underside. The perfect surfboard is elusive with hidden dangers built into designs. There is hope that perfection, like a beautiful fragrant flower, will blossom in the future.