Pics: Oli Lane-Peirce
Hydrofoils (foils) come in all shapes and sizes and fit many types of flight discipline. Some cover all the bases whilst others are targeted towards specific styles of foiling. It can appear confusing to those getting involved for the first time, with many combos of different length fuselages, foil masts, stabiliser wing sizes and types and front wings. As you get more into foiling you’ll probably start looking at all the techy bits and start experimenting with the component parts. For this article, and the beginning of your foiling journey, it’s the front wing we’ll be focusing on.
Low aspect foils
When starting to fly you’ll be wanting two main things: early take off and stable flight. Both elements will see you progress rapidly. To achieve both, however, the best course of action is to choose a low aspect winged foil. These are the wings that appear most shovel-like. They’ll be wide (span) with a fairly long chord (nose to tail). And they’re usually quite thick at the leading edge.
Low aspect foil wings are often referred to as surf wings. That’s because they’re a tad slower than higher aspect, designed to stay in contact with the wave (rather than outrun it) when surf foiling. They also provide tons of power and lift resulting in as early take off as poss. In addition, low aspect wings are often quite carvey, designed to swoop and turn as you would when surfing conventionally.
For wing surfing purposes low aspect foils are a good choice. Wings are low power ‘engines’ without the efficiency of a rigid power source like a windsurf sail for instance. As such using your wing in partnership with a low aspect foil will result in airborne fun quicker than if using a high aspect foil – at least during those initial steps. The rail to rail stability of low aspect foil wings also allows riders to get comfortable once at altitude and hopefully progress to nailing those first gybes. Also, if you actually want to progress your winging to surfing, where you use the wing to tow into swells, flagging the wing behind you once on a wave, then a low aspect foil will be the best choice.
High aspect foils
Generally, high aspect foils are the exact opposite of low types. They’re much thinner, have a thinner chord, are a bit more unstable, need more power to lift and are faster. As such any wing foiler‘s technique needs to be much more dialled in. But, once flying on a high aspect foil the stock factor can be through the roof, such is the speed you get vs the actual true wind strength.
Any winger switching from low aspect to high will struggle to go back, such are the benefits. Foil brands have been beavering away at the design table trying to get high aspect foils as user friendly as possible – and it’s getting there. You can still use a high aspect foil for things like surfing, but you’ll need a bit more experience to get the most out of it. Where this type of foil really comes into its own is if you’re planning to jump. You can, of course, boost a low aspect, but the additional speed of a high aspect foil will usually see wingers getting much more sky time.
As much as you can split foil types into high and low aspect you can also split these categories down further by describing some hybrid designs as mi-aspect.
Mid-aspect foils aim for the best of both worlds. It’s not quite as cut and dry as that but for the purposes of this article, we’ll keep things simple. Some mid-aspect foil wings err to the lower end of the spectrum whilst some vice versa. Ultimately, whatever type of foil you’re looking at you should have an idea where its strengths lie and what you’re likely to find when using it.
Research is key with any new purchase (whether watersports equipment related or not). Look up details online, scan the web for reviews (although don’t put 100% of your faith in these as sometimes reviews can be biased one way or the other). Talk to your retailer who should also be clued up. Ultimately get as much knowledge about foils and foiling as you can if you intend taking the leap and getting involved.
We’ve talked a lot about hydrofoils in this series but we appreciate that those of you reading may yet have the knowledge regarding foils, types of foil and their differences. Whilst McConks doesn’t supply foils (yet) for this part of the windSUP/windsurf/wing surf/wing foil guide we thought it a good idea to shine a spotlight on them.
Hydrofoils are made up of five component parts: foil head (the bit that attaches to your board – either deep Tuttle or US Box track mount); foil mast (the upright strut); fuselage (the long strut which the foil mast attaches to and has front and rear wings attached); front wing and stabiliser (the foil‘s rear wing).
A lot of companies manufacture their foils in modular fashion. Differing fuse lengths, mast lengths, front and stab wing sizes are all interchangeable meaning riders can mix ‘n’ match and find a set up that best suits their style or styles of riding.
Modular foil components and hydrofoil sizing
For wing foiling mast lengths usually between 70cm and 90cm long is best. The longer foil mast gives more leeway in terms of overfoiling (or cavitation) when flying along. SUP foilers, meanwhile, will tend to opt for 60cm-70cm foil masts as they’ll be riding in shallower water. Shorter masts can also be a bit zippier for tighter turns.
Longer fuselages will help with earlier take offs and give better stability with shorter being better for manoeuvrability.
Front wings is where you find the majority lift from hydrofoils although rear stabiliser wings also provide this. With some rear stabs you can alter the angle of attack to induce earlier lift or more control. And depending on where you place the foil mast along the fuselage will also affect lift as well as overall feel of the foil. Being able to move the foil wing forward or back will allow riders to find the perfect balance. Centre of lift should ideally be between front and back legs but as you get better you may want a slight front foot bias. Modular foil products allow all of this tuning – you as the end user just need to tweak until you discover best fit.
Low aspect vs high aspect
In general you get two types of hydrofoil wing: low aspect and high aspect (you can also get medium aspect wings but these tend to lean towards either high or low aspect designs depending on the brand). Low aspect wings (generally) give earlier lift but are slightly slower (slow speed being relative in the grand scheme of foiling). They’re usually easier to manoeuvre and offer better rail to rail stability. Low aspect wings have a wider chord (nose to tail) and resemble shovels.
Higher aspect foil wings, in contrast, are thinner and narrower. They can still have considerable span – especially the types designed for super light wind or uber small wave performance – but are generally faster.
Most foil wings are manufactured in pre-preg carbon although some brands do offer alternative construction materials such as G-10. Carbon is generally seen as the highest performance material. A full carbon hydrofoil set up will offer the least amount of torsional flex so is arguably more efficient.
It’s not uncommon to find foils with a mix of aluminium and carbon. The foil mast and fuse are made from alloy whilst the wings remain carbon. Some companies also use steel. Full carbon foils are the most expensive whilst alloy/carbon are cheaper. For the everyday foiler carbon/alloy, from a reputable brand, will be more than adequate – in fact, you may never need to change to a full carbon set up. If you get into the high performance end of foiling, such as tricks and moves (where air time is a thing), then you do run the risk of breaking/bending foil parts. That said, plenty of riders do this kind of thing on non-carbon foils without issue.
Foils for winging
If you’re looking at wingfoiling, and wondering what foil to stump up for, then consider that winging is a low power discipline. Therefore a foil set up with a larger front wing surface area is a better call for average weight riders (80-90kg) looking to wing in moderate breeze (15-20 knots) and achieve the earliest amount of lift. Smaller stature wingers will get away with smaller wings.
As you progress, and your skills improve, it’ll be possible to drop the front foil wing size and increase elements like speed and/or manoeuvrability. But, keeping hold of your bigger foil wing will always be worthwhile if you plan on tackling super light breezes around 10-12 knots.
There are now lots of brands that produce hydrofoils for all kinds of flying. It’s a bit of a quagmire when you’re first starting out as you can’t demo kit if you can’t actually foil. There is, however, lots of advice available online, and here at McConks we have access to reputable knowledge so could point you in the right direction. We’d also suggest getting a lesson a good idea. Wing foiling, SUP foiling and foiling in general is super fun. Gear has got a lot more user friendly so there’s no better time to learn. Hit us up with questions you might have about hydrofoil, wings or windSUP/windsurfing.