Seattle based powered hydrofoil concept project. who’s interested?

Discussion in 'Projects & Proposals' started by Jonathan hintzman, Jun 15, 2018.

  1. Jonathan hintzman
    Joined: Apr 2018
    Posts: 6
    Likes: 0, Points: 1
    Location: Seattle

    Jonathan hintzman Junior Member

    hello everyone and welcome to my new thread. This will be my first hydrofoil project and I am very excited for it. First let’s start with the hull design. My ideal design is a 20’ multi hull, Based on a racing kayak or one of the many foil cats hull shapes but with short forward out Riggers. Imagine if you took a small trimaran but the outriggers were only 3 or 4 feet long . For the Proto type I would like to machine the hull as one piece out of rigid foam and fiberglass over the foam. This is a monocoque design meant to have one continuous layer of fiberglass Throughout. Similar to some cheap sit on top plastic kayaks the cockpit will be built in to the hull as one continuous piece. The forward foils will be mounted aft Of the outriggers. the rear hydrofoil will be mounted on the transom to an adjustable height engine mount along with the outboard. The forward foils will hopefully, possibly, have two options for driving first and foremost they will have a mechanical linkage to self writing feelers mounted in front, secondly a cable system mounted to hand controls for high speed left and right control of the foils as well as angle of attack. This is to control the angle of the boat in high-speed turns from port to starboard. the rear foil will have an adjustable angle of attack as well as turning capability. With this system the boat should fly a bit like a plane from the controls. Honestly I am too embarrassed to upload my crude sketch of my design but I probably will anyways. I am ordering Ray Vellinga book hydrofoils, design, build, fly and will read it but I am worried that the info might be ( no offense ray) a little outdated. But I am sure that I will gain a ton of knowledge from his work no matter what.
    My knowledge of hydrofoils is this, foil creates lift and as per Bernoulli‘s principle the lift is equal to the weight of the vessel the drag of the foils and the speed of the boat. So at some point you reach maximum speed dictated by your foils ventilating. So if you want to go faster you need smaller foils with less area and less lift. I’m starting this project with a small motor for financial reasons But would like to be able to increase the motor size and the speed when I can afford to Without changing my foils but if I have to then no big deal. I’m Leaning towards using T foil design but if anybody thinks that I would be better off with L or Jay foils let me know and tell me why. if you could supply me with any sort of information on the mechanics of controlling the foil system it would be appreciated.
    If anybody in the greater Seattle region or anywhere in the world would like to collaborate on foil design and mechanics I would greatly appreciate the help and if you can make it here you can take her for a spin anytime you like we could even build a second boat for you Provided you supply the materials and probably labor or compensation for labor. Ok I did it here is my crappy drawing. I’m downloading shapr3d and learning though I’m sure I’ll be done with this project before I can draw a 3D smiley face. Me and my dad are going to build this boat in his shop in mukilteo. It’s our father son hot rod project. In the future I would like to build some more for money. I think it’s an awesome design with some cool features. I am almost worried that I shouldn’t post this much detail to the internet for fear that someone will patent it and run away with it or try to sue me out of production but there are plenty of small foils out there for people to rip off. I hope we can build up some collaboration on this. This forum is a great tool for designers and inventors and I appreciate the participation of so many enthusiasts.

    Attached Files:

  2. Nickmac
    Joined: Jul 2018
    Posts: 2
    Likes: 0, Points: 1
    Location: New Zealand

    Nickmac New Member

    Hi Jonathon. I have been contemplated a trimaran design hydra foil for some time now so look forward to any information you receive.
    My idea was a t foil forward of the central hull with L foils on the outriggers as the can be self adjusting for ride height as used in America's cup catermarans. Also this configuration allows for the foils to be lifted for beach and trailering. I have seen carbon Fibre t foils for wind surfers which I believe could be adapted. My biggest problem is I require help with what hull form would be be best for the intend use. Let's hope we can get some positive advice.
  3. BlueBell
    Joined: May 2017
    Posts: 2,002
    Likes: 597, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . . .

    Ray's book is not outdated but it is somewhat pedestrian. I have a copy.
    I'd ditch the twin outboards, one prop is more efficient, lighter, and way cheaper.
    I'd use a 20' surf-ski and add your amas.
    Structurally, you'd be better off with your forward struts under the crossbar, lighter too.
    J-foils up front would be preferred but a centre T-foil would be better but would require some R/C stabilization servos to control ailerons for roll stability.
    Involving flaps would give better all-round performance, lower take-off speeds and higher top end speeds.
    How much do you weigh?
  4. Nickmac
    Joined: Jul 2018
    Posts: 2
    Likes: 0, Points: 1
    Location: New Zealand

    Nickmac New Member

    Completely agree re one outboat far more efficient with less drag and a better power to weight ratio.

  5. Doug Lord
    Joined: May 2009
    Posts: 16,679
    Likes: 346, Points: 93, Legacy Rep: 1362
    Location: Cocoa, Florida

    Doug Lord Flight Ready

    "J" foils* are called "uptip" foils by their inventors and have automatic altitude control based on leeway coupling. Using them on a powerboat and expecting automatic altitude control is wishful thinking...unless the foil is designed as a "V" foil with a side strut. Uptip foils are also called "L" foils and several other names invented by the masses(!).
    *Unless they are the original "J" foils on the Hobie trifoiler!

    PS- Ray Vellinga's book is excellent!
    Last edited: Jul 18, 2018
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.