What do you get when you combine a cheap RC boat from Walmart, foam board, a couple powerful motors, and some aluminum cans? Most people would just end up with a pile of garbage, but we’ve already established [Peter Sripol] is fairly far from “most people”. In his hands, this collection of scraps turns into an almost unbelievably nimble seaplane, despite looking like something out of a TailSpin and Mad Max crossover episode.
In his latest YouTube video, [Peter] takes viewers through the process of turning one of these rather lame RC boats into an impressive flying machine. His took inspiration from the Sikorsky S-38, an American amphibious aircraft introduced in 1928. The S-38 looked like a fairly traditional boat bolted to the bottom of a set of huge wings, so it’s little surprise that he patterned this build after it.
The construction of the seaplane is very simple, and boils down to cutting some big wings out of foam board, using some sticks to give it some rigid framing, and putting a tail on it. The biggest problem is that the boat’s hull lacks the “steps” that a seaplane would have, so it’s not an ideal shape to lift out of the water. But with enough thrust and a big enough control surface, it all works out in the end.
Which is in effect the principle by which the whole plane flies. There’s a large elevator cantilevered far astern to help leverage the boat out of the water, but otherwise all other control is provided by differential thrust between the two top mounted motors. The lack of a rudder does make its handling a bit sluggish in the water, but it obviously has no problem once it’s airborne.
If [Peter] and his foam board artistry seem familiar, it’s probably from the not one but two homemade aircraft he built with shockingly similar techniques to this current project.
Massive thrust and OK lifting surfaces? Amazing job! :)
“The biggest problem is that the boat’s hull lacks the “steps” that a seaplane would have, so it’s not an ideal shape to lift out of the water. But with enough thrust and a big enough control surface, it all works out in the end.”
Yup that was first thought, that it would be hard to unstick, but keeping most of the hull ahead of CG and stern near rotation point seems to have worked. Not too dissimilar from early flying boat styles until the need for step was understood.
The “step” is the back end of the boat and will work just fine as he has enough control surface throw plus excess power. Historically we’ve seen even Snoopy’s Doghouse fly when granted enough power and throw.
He certainly is good at the models!
The saying goes that anything with enough power is an aircraft.
Can anyone explain how it’s able to spin like that if it’s only got differential thrust and no control services on the wings? He did a couple rolls that seemed impossibly fast/tight. Unless it’s just the perspective throwing me off.
I don’t know squat about drone motors but these seem pretty high end in their world
https://www.lumenier.com/products/brushless-motors
4 of these motors (with propellers attached of course…) will throw an entire 1+pound quad around like nothing…said quad has 0 lifting and control surfaces…
If you have enough trust, aerodynamics are just a nuisance ;-)
This would be a flying boat, not a sea plane. A flying boat lands on the hull, a sea plane has pontoons instead of wheels.