Hobie Cat Forums

A small UK group of engineers http://www.c-fly.co.uk/team.html have researched, built and tested what they feel is the best hydrofoil technology for sailing in the open ocean where waves normally can cause the boat to pitchpole. They describe their technology on their website at http://www.c-fly.co.uk/concept_hydrofoil.html and now are considering what markets to go after including the dinghy http://www.c-fly.co.uk/story_future.html . See their latest experimental hydrofoil cat sailing at http://www.youtube.com/watch?v=MHhWQ64Uqt8. Or here http://www.youtube.com/watch?v=lEqYTrzaHsc&feature=related

What intrigued me was the fundamental stability built into the design without any complex controls or sensors as is normally used and the canard bowfoil to offset pitchpoling at high speed. So perhaps last year's April fools day "hydrofoil TI" photo may not be so far fetched any more.

Bob

Reminds me of the triangular foils used on Italian yachts 40-50 years ago.
The James Bond movie Thunderball had such a hydrofoil yacht as the main gadget.

bobco :
Pretty interesting concept, you can tell these guys have their thinking caps on.

The steering canards are brilliant, my thoughts are that their concept would be very good for cats because of their inherent low drag, short length and very tall sails.
Trying to get something like this to work on a TI would be a different story though (because it's a tri).
I wish them luck.

C-Fly gives credit to the Canadian hydrofoil project Bras d'Or which was a sea going 200 ton hydrofoil ship in the 60's and pictured here at http://www.foils.org/brasdorp.htm

An interesting photo history of mostly powered hydrofoils as depicted in popular magazines is at http://www.foils.org/popmags.htm

The C-Fly sailing hydrofoil cat also sails well in normal displacement mode but doubles its speed when the retractable foils are deployed. So perhaps a future hydrofoil TI might sail in light winds as a trimaran like now with mirage drive and rudder operational but as winds pick up and it deploys the foils it becomes a catamaran much like the Trifoiler except there would be no rudder foil for lift or steering since steering would be via the front foils of the cat.

Bob

seems like a great addition to the Hobie line but you might have noticed a few key differences...

1. the amas were much longer than the main hull
2. exetremely high rig strength, main hull supported by the akas
3. exetremely ridgid hulls, able to support the entire rig from just 4 points

so Hobie needs to step up and make the TI in carbon fiber...


look at their ocean rig, it's a tri

j

_________________
2011 Golden Papaya TI with a 250 square foot spinnaker!
also a more manageable 100 square foot spinny...
&
the TI3 rear ama mod

You're right, I hadn't noticed that but when you look at the 3D model of C-Fly Ocean here it is more apparent. http://www.c-fly.co.uk/vid_ocean.html

Of course this is not an add-on kit to the TI but rather an entirely redesigned boat. What is the real advantage of the TI is its versatility - to cover such a wide range of conditions all in one craft - trying to keep all that such as the mirage drive and low wind or no wind transportation yet also add the thrill of really fast sailing - that is the dream that may be possible someday.

The moth http://www.youtube.com/watch?v=NCY1EAp9FfY is a small hydrofoil sail boat but is quite difficult to sail. The C-Fly technology seems to take the high skill and instability out of hydrofoil sailing. They are thinking of doing a dinghy version but of course it will not have the mirage drive and the TI advantages.

Bob

Reasons why a TI is incompatible..
1) Sail area is way too small for the weight for foiling capabilities
2) Mast is unstayed, therefore sail control is not precise enough
3) Hull platform is no rigid enough to take the loads

I could go on, but the AI/TI is a totally different design for an entirely different market, and it is a perfect fit for its design aims. What you are suggesting is like making modifications to a sports car to make it competitive in Formula One

Hobie had a light weight trifoil a few years ago that was a real rocket.
But from what I gather, the foils were easily damaged. The few Youtube videos I saw were very impressive. Sort of owning a race-track qualified Ferrari. I guess there may be a few of them out there somewhere if you want to buy a foil.

Yes I looked at a Hobie Trifoiler for sale here in Virginia for about $9K but I was told that the it is complex so difficult to keep running well. But if possible to build a retractable foil system in a TI size boat then I believe there would be a good market.