More stern lift, improved stability, handling and fuel efficiency sounds amazing right? It is, and outboard hydrofoils like Permatrim can deliver that on the right boat and motor set-up.
Hydrofoils are the plates that bolt on your outboard cavitation plate, which increase the surface area of the plate. They work by lifting the boat out of the water as the boat gathers speed, creating less drag. This helps to increase acceleration, giving you more power and reduced strain on the engine. The faster you go the more lift the hydrofoil gives.
A correctly fitted foil has numerous benefits like the ability to plane at lower speeds and increased trim control, which is especially important as sea conditions change. Plus, they can stop a boat porpoising – i.e. bouncing up and down at high speeds.
While they don’t look particularly impressive, they can have a big impact on boat performance.
So how do they work? This basically boils down to fluid dynamics - water moves faster over the top of the plate than the bottom creating a drop in pressure below the foil, which gives it lift.
To help determine if a hydrofoil will help, we’ll ask the following four questions:
If any of this applies to you, chances are a hydrofoil will significantly help. However, bear in mind that they affect every boat and motor differently and it’s not a one-size-fits-all fix. The only way to know for sure is to trial it. When sea-trialing always make sure you do this with the load and crew you’re likely to take the majority of the time as this can have an impact too.
Also, the smaller the boat the more significant the effect of the hydrofoil is.
They cost approximately $38-$200+ depending on the size and type. However, if you need them you’ll save money on fuel and wear and tear on the boat anyway. And it’s a small price to pay for more enjoyable boating.