Surfing has evolved with flight. The playing field has forever changed. In smaller waves, surfers take to the sky, performing high aerial tricks with successful water landings. In large waves, the skills required to land high aerials has transferred. Surfers are successfully landing free falls in big air drops, using very small boards. This has come with a price, as many injuries occur in flat landings. Improved landings can improve surfing and reduce injuries.
In flight, the flat bottom provides lift. The board becomes a wing, air pressure or lift under the board exceeds pressure from the rider's weight, providing flight (Bernoulli's Principle). The same principle applies when a surfboard planes on water. Speed on water generates lift on a flat surfaces. Speed and a flat surface are essential factors to planning on water, but; the factors can work against a surfboard with high nose rocker.
The nose area does not provide much lift in flight, due to the nose rocker bend and reduced surface area. Air spills around the rocker bend, therefore; the nose section can be modified to improve landing without affecting flight. The nose area may not generate much lift in the air, however; it can provide hydrodynamic resistance on water, especially on a hard fast nose landing.
The nose bend or nose rocker creates a bow area under the nose of the board. The bow is usually out of water when a surfboard is planning. When the bow enters the water, the surfboard is not planning at optimum speed. The bow moves water out of the board's path and the board decelerates. The bow becomes a landing pad in air drops, due to the angle of attack and gravity. With speed, high impact on the bent area of the nose can push the board back. Water does not move out of the way and lift is created by the flat surface and speed.
At high speed, water is not pushed out of the way fast enough. Water unable to move, becomes impenetrable by a flat surfboard surface. At the perfect angle of water impact with a flat bow, the board can abruptly stop. In a hard high speed landing, the flat bottom bow does not part water. It does what it is designed to do, which is to produce lift. A round or vee bow pushes water aside and cushions impact. This is a design used by most boats, canoes, kayaks and surfboards from the past.
Tom Curren former world champion, pioneered modern surfing. Together with Maurice Cole they introduce the reverse Vee or forward Vee, far ahead of their time. This board rode seamlessly through transitions, even when it got airborne. Forward Vee parts water and cushions impact, preventing surfer catapults. Watch Tom's seamless transitions in the next video.
An ending note: A nose or a tail landing differs, with weight directly over the landing end, because a surfer's weight parts water with gravity force on impact. The nose or tail sinks under the surfer's weight, water is pushed aside. Water is also successfully pushed aside by a flat bottom at lower speeds.