I don't think that inline would work, as the 'downwash' (if that's the right word) from the first fin would affect the fin behind.

Twinsers or trifins would be the way to do things, sort of like how a biplane or triplane works -- lots of surface area for not much span.

If you look to cars for inspiration, sometimes they use a thing called a gurney flap. This increases the lift, and is useful when you're restricted in span. A longer span is more efficient, but since we're chasing flat water... Gurney flaps look horribly inefficient though.

I think that the best solution would be a fin with lots of chord and not much depth, similar to some formula fins that are designed for shallow water.

Little weedies, but very iffy sailing in that kinda shallow water

Dartboy said...

Sure beats someone having to wipe your arse for you for the rest of your life

I thought thats what kiting is all about.





On topic I once rode a Bonzer board with a bunch of little fins in series. Probably not the fastest of boards but you could sail in very shallow water.

Ah yes..... the old Mistral Take off!
Twin folding fins..
Guaranteed to entertain when you reached 20 knots..

Thanks for the input.
PeteClifford, I think you are on to something there! Brilliant.
Regarding the thruster fin configuration: I have an old tri fin wave board. Its as slow as! I have been told its because of the fins. If the fins were more of a speed fin shape rather than a wave fin shape would that help (assuming they were on a slalom type board)? ie could you have a fast board with 3 small fins? If yes, why hasn't anyone done it? There must be heaps of flat water just waiting to be blasted across, aside from the fact its only 6 inches deep!!

PeteClifford said...

Here's what I've been working on recently. It's an alloy fin that fits both US box and Tuttle and will kick back if impacted with the sea bottom, reef etc.
The fin is held into the head by sideways pressured applied from the forward bolt.

Hmmm.... what about a folding fin so if you hit the bottom it just retracts upwards and back? I could think of a few places and times I would have liked to have had one here at the PiT!

Hey Pete is that my fin I want it for Green and for West Aus next year, I'm going crab hunting

elmo said...

firiebob said...

PeteClifford said...

Here's what I've been working on recently. It's an alloy fin that fits both US box and Tuttle and will kick back if impacted with the sea bottom, reef etc.
The fin is held into the head by sideways pressured applied from the forward bolt.

Hmmm.... what about a folding fin so if you hit the bottom it just retracts upwards and back? I could think of a few places and times I would have liked to have had one here at the PiT!

Hey Pete is that my fin I want it for Green and for West Aus next year, I'm going crab hunting

Ssswwwweeeeeeeeeetttttt

PeteClifford said...

Yeah Bob, I've got a few fins for you to try and your next PB is not far away. I had my first try at anodising yesterday and the fin was suppose to be firetruck red. Not a bad shade of pink anyway.