​Bio - Eric L. Mihelbergel is an intermediate/advanced windsurfer, kiteboarder, and foiler living in the Great Lakes Region of New York State who enjoys sharing about windsports and fitness.

Difference Between Windfoiling and Windsurf Wave Foiling
(Written July 2023)
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Important: See the TEST below to know if you are windfoiling or windsurf wave foiling.

After more than three years of windsurf wave foiling (WWF) I have finally learned enough about the mechanics of the gear that I now understand why it is such a dramatically different sport than traditional windfoiling. (See TEST below to know if you are truly windsurf wave foiling or if you are just windfoiling). In the beginning I didn't realize there was any difference. I simply saw one group of people with a sail on a board with a foil underneath who were having no success and lots of frustration, and then I saw another group of people with a sail on a board with a foil underneath who were having good success and a ton of fun surfing waves. At first I thought it was differences in skill. That was partly true in a small way, but it certainly was not the major difference. Let's take a look at how vastly different the gear mechanics are between these two sports.

To begin, let me first describe how the gear of the two sports appears different from a simple visual inspection. I will use my perspective from when I was a beginner to illustrate the grandeur of my ignorance at the time. As I observed foil riders at the beach and on videos I noticed one obvious main difference. The traditional windfoil gear had the foil mast mounted right near the tail of the board while the WWF gear had the foil mast mounted about 12-14 inches from the tail of the board. At the time I did not understand the significance. I understood that the WWF boards were basically modified SUP foil boards, but I did not know why that made it such a dramatically different sport. I also noticed that the foils on the windfoil gear were much smaller, thinner, flatter, and higher aspect than the foils on the WWF gear. I understood that the larger foils provided more lift, but that was the extent of my understanding. These were the two differences that stood out to me at the time.

Now let us briefly discuss the objectives of each sport so we can later align those objectives with the gear and illustrate the mechanical gear differences between the two sports. The main objective of traditional windfoiling is to go fast in a straight line. It's pretty simple. There just isn't much else you can do with that gear. The main objective of WWF is to be maneuverable and surfy while travelling at a speed that is matched to the speed of the waves you are riding. Some waves are fast while other waves are slow, so the gear must be matched appropriately. A fast, small, high aspect foil will not maintain lift when you slow down to ride small slow waves, and a slow, large, low aspect foil will blow up when you try to ride fast, steep waves or blast on flatwater.

With the fundamental prerequisites laid out above we can now begin to discuss the gear differences in more detail. As with regular windsurfing the gear stems from the objectives. With the main objective of traditional windfoiling being to go fast in a straight line it makes sense that my early observation of small, high aspect foils would be necessary. Small, high aspect foils are faster and more efficient than larger low aspect foils. But in order to get these small high aspect foils to lift a board and rider out of the water, and maintain that lift, a relatively larger sail will be needed, compared to using large low aspect foils, as it will be necessary to have more power to increase the board speed to a speed that will initiate and maintain lift. With the objective of speed comes the necessity for stability. Greater pitch stability can be achieved by using a longer fuselage that puts the front foil wing farther in front of the foil mast when windfoiling compared to the setup used for WWF where the front foil wing is very close to the foil mast which allows it to be more maneuverable. 

All of this leads to the next feature which is the size of the rider compartment. The rider compartment is the distance from your stance (foot position or foot strap location) to the mast foot of the sail. Since larger sails are used for traditional windfoiling, as we noted above, the harness lines will be farther back which means the rider will be farther back which means that the rider compartment must be slightly larger to accommodate the greater space that the larger sail takes up. When I am on my WWF gear and sailing with windfoilers they are usually on a sail that is about 1-2 square meters larger than the sail I am on. That is a big difference. The larger sail is heavier, so the rider must be slightly farther back to compensate for the added nose weight from the sail (all other things being equal), thus contributing to a larger rider compartment. The smaller high aspect foil provides less lift, so the rider's feet must again be slightly farther back to compensate, thus contributing to a larger rider compartment. Everything is farther back with traditional windfoiling in a more regular windsurfing stance compared to WWF, and this requires a larger rider compartment. WWF is much more front footed and forward thus requiring a smaller rider compartment.

Now let's think about board volume. Suppose that we want to design a board for each sport that is 120 liters so that we have the same adequate float for slogging and uphauling with ease. Since the traditional windfoiling board will require a larger rider compartment than the WWF board it is easy to put volume in that middle area of the board where the rider compartment is located simply because there is already the need for length in the rider compartment. But the WWF board will have less length in the rider compartment, so that volume will have to go somewhere else if we want to arrive at the same 120 liters of desired float. If we put that volume in the length of the nose then we will have too much swing weight to achieve our objective of maneuverability. If we add that volume to the thickness of the board then we sacrifice total length of the board resulting in loss of glide that is important to get up on foil with the small maneuverable sails we want to use in order to keep our kit super turny and surfy. Hence the extra volume must go into a board tail that extends 12-14 inches behind the foil mast as observed near the beginning of this article. This location for volume does not affect swing weight and still gives us an extended surface to allow for glide needed to get up on foil. None of this was obvious to me when I first began observing the two sports.

The mechanics of the gear that we laid out above allow the WWF rider to be in a front footed surfy stance that is closer to the mast base for a super maneuverable experience similar to surfing, while the traditional windfoil rider assumes a more rearward back footed stance for a fast experience similar to regular windsurfing. The WWF rider can ride waves efficiently in a surf stance while the windfoiler can go faster and blast with more pitch stability. The larger, low aspect foils of the WWF gear make the sport much easier to learn and easier to ride even in flatwater. Because of this many windfoilers on traditional windfoiling gear are now choosing WWF gear for their flatwater riding. Yes, WWF gear works for a flatwater windfoiling experience. You go slower, but it's much easier. It's not optimal for speed and blasting, but it's still fun. And that leads us to a similar discussion about riding in the waves. Just because you ride WWF gear in the waves doesn't mean you are actually participating in the sport of WWF. Are you actually windsurf wave foiling or are you windfoiling in the waves with your WWF gear? They are two different things. How can you know if you are actually WWFing? Here is the test:

TEST:  If you can ride down a wave, flag the sail, completely let go of the boom with one hand, and comfortably maintain glide as a result of the push from the wave then you are experiencing the true essence of windsurf wave foiling.

If you recall from my previous article Windfoil Wave Technique, the sail is flagged out and the force of the wave is used for speed and power. Flagging of the sail is achieved by moving the hands up the boom directly next to the mast with one hand on each side of the boom. Then let go with one hand to know that the sail is completely flagged. If you are on the proper spot of the wave then you will continue to glide effortlessly. If you immediately start to slow down and come off foil then you know you were using the wind for power and speed and not the wave. It's a simple and easy test that always tells the truth. You will learn very quickly how to use the power of the wave instead of the power of the wind. It is a great learning tool. This is the essence of windsurf wave foiling as opposed to traditional windfoiling. The gear and setup provide us with the opportunity to surf instead of sail. It is a magical thing!