This post is written with monoplane/monohull configuration in mind although it generally applies to most other hull types.
A boat that travels on top of the plane of the water is known as a boat on plane. This is when a boat has the front lifted out of the water. Your speedboat will plane out only if it has a good prop driven by sufficient power (a good motor and sufficient battery power). Without sufficient power, the boat will travel with the front fully in the water trying hard to break through the waves at all time, which can be slow.
Picking a proper motor is one key success factor for a boat to plane out.
If you are using brushed motor, these are the general guidelines:
- For a direct drive boat that is not longer than 1ft – a 380/390 class motor would do fine.
- For a direct drive boat that is about 1.5ft long – a 540/550 class motor would be necessary.
- For a direct drive boat that is 2ft long – you must use a 750 class motor!
If you are using brushless motor, these are the general guidelines:
- For a direct drive boat that is not longer than 1.5ft – a 380 class BL motor would do fine.
- For a direct drive boat that is less than 2ft long – a 540 class BL motor would be good enough.
Another thing – generally, use a metal prop on a larger boat that is more powerful. For a smaller boat, plastic prop may just be fine.
550 motor, 3S, direct drive:
When a boat is “on plane”, it means it’s riding up on top of the water rather than pushing through it. At low speeds, a hull moves in displacement mode—the boat is basically plowing through the water, the bow is up, the stern is down, and you see a big rolling wake behind it. That’s slow and inefficient.
As speed builds, the hull shape and thrust work together to lift the boat. The bow drops down, the stern rises, and suddenly the boat is skimming across the surface instead of fighting against it. That’s planing—and it’s where RC speedboats really come alive.
On plane, you’ll notice a few things:
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The boat feels light and fast, carving across the water with much less drag.
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The wake sharpens into a clean V-shape instead of a big rolling wave.
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Acceleration and handling both improve dramatically because the hull isn’t buried.
Think of it like an airplane wing taking flight—the hull generates lift, reducing drag, and letting speed multiply. That’s why proper motor and prop sizing is so important; too little power and the boat never planes, too much prop and it might bog down before it can lift out.
When your RC boat is on plane, you’ll know it instantly. The nose levels out, the boat leaps forward, and you get that perfect, smooth rooster tail—proof that you’re not plowing water anymore, you’re dancing on top of it.