High Performance MPX Foil/Self-righting Trimaran-The Test Model

Fire Arrow Foiling System Testing and Development

Above the original post describing the new adjustable wands I'm using now.
Pictures below:

 

Fire Arrow Foiling System Testing and Development

Fire Arrow:

 

Fire Arrow Foiling System Testing and Development

Fire Arrow foiling in a 5 mph breeze:

 

Its a bird, its a.........

Pelican on the very peak of the roof on the dock in front of my place. First time in 9 years I ever got a shot like this! Get a couple other birds-Heron often, seagull now and then but never a Pelican on the peak of the roof-they usually stand to the side like the one in the second shot. To get some perspective on this roof see the background in Fire Arrow post 2192:





And a friend:

 

Fire Arrow Foiling System Testing and Development

This video was exactly two weeks before her first 100% full foiling video in 2014-very light air:
https://www.youtube.com/watch?v=FF7cy8AoFnU

 

Happy Thanksgiving, Doug. That is a great pelican photo.

 

Happy Thanksgiving to you too, Hoyt! That was a special Pelican-had a need to be at the apex of the roof.
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And to everyone else: Happy Thanksgiving!

 

I have temporarily given up on wand-controlled T foils for now and reverted to V foils

Action from Sunday is here

https://www.youtube.com/watch?v=JMR-xlewhgg

We have a couple of new ideas, mainly centred on how to vary the angle of V foils whilst the boat is sailing

Meanwhile I need to make a smaller rig . . . .

 

RC Foilers

Breathtaking offwind speed! Looks like maybe not enough RM upwind?
Were you using the movable foils in this video?
https://www.youtube.com/watch?v=JMR-xlewhgg

 

Both trimarans had fixed V foils on, as seen at the start and end of the video. Still pondering on how to adjust the foils at speed. Have added winglets to the Firedragon foils this week so will test these next weekend, along with a shorter rig to improve the righting moment. Another decent breeze forecast

 

RC Foilers

Have you considered a linear servo? At the beginning of the vid I didn't see any views of the top of the foils but under sail I thought I saw something that allowed foil rake adjustment-hard to tell.
Good luck-it'll be interesting to see what you come up with....
PS- Do you want to get the windward foil to go negative for downforce?
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A guy on a the aero-hydro forum here who has a tri with "V" foils said he had considered trying to get downforce but that it probably wouldn't work: since "V" foils are surface piercing foils and ,as such, reduce their immersed area when at a positive AOI, but when that is changed to negative the exact opposite happens. Assuming relatively steady speed there is nothing stopping a surface piercing foil from rapidly increasing area and therefore downforce even starting with a very small negative AOI-in other words it becomes unstable. I'll try to find it and post a link.

Here is Doug Halsey's post with the part I was talking about in red:
(The thread this is in is here: http://www.boatdesign.net/forums/hy...itation-lower-speeds-than-expected-53927.html )

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Dougs foiler "Broomstick":

 

RC Foilers

==========================================
Ian, have you ever considered using movable ballast (like Hydroptere does)?

 

Some decent wind this weekend:

Saturday is here


https://youtu.be/sqyOmN86xZw
You will see on the rear port cross beam there is some yellow tape. This is holding 300gms of ballast. Helped on the reaches

And Sunday is here

https://youtu.be/m25y85KXm38


I seem to max out at 22km/hr! Probably need slimmer and thinner foil sections

Both boats now have winglets on the tips of their foils and this definitely helps with directional stability. Am not skidding sideways as much now

 

RC Foilers

Great stuff, Ian!!

22km/hr=13.67 mph

 

Action from Saturday is here

https://youtu.be/ZN8mcWJgtZg

We are getting the Mini40 to stay up on its foils for longer now
The second part of the video shows our One Metre back on the water, and it was performing better than before. Its all a question of putting up the right rig for the wind strength.