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

Really like the aft sections of the vaka shown by the picture of the upturned hull for painting.
Keep discovering interesting thinking you've built into these boats.
Kudos.

 

WOLF --- Thank you, Tom! I hope that I will be able to get the boat built. This little model is intended to show what a smaller "sport boat" version of the Fire Arrow would look like and serves as a convenient way to work out the details of the Wolf design.

 

Fire Arrow Foil System---there are now FOUR trimarans using the basic Fire Arrow Foil System which was conceived of right here.
It's an exciting time for trimaran design with multimillion dollar Teams investing in a Foil Configuration remarkably similar to the Original Fire Arrow system tested and proved on July 24th, 2014 and further proved by the fantastic work of Guillaume Verdier on Maserati and his current masterpiece Gitana 15. And just recently it became apparent that the new Banque Populaire is adopting the same basic system and will launch soon.
Here are all the boats in order of their development:

#1--Fire Arrow-designed and developed on boatdesign.net-the first trimaran in history to use the unique foil system which consists of a lifting foil on the daggerboard capable of downforce as well, two UptiP ama foils-used because of their automatic altitude control and a rudder t-foil:


#2--Maserati-a mod 70 converted to use the same basic Foil System as Fire Arrow completely independently by Guillaume Verdier-the first time the system was used on a fullsize boat:



#3-- Gitana 17--the first fullsize trimaran in history designed and built from scratch to use the basic Fire Arrow Foil System, this version designed by Guillaume Verdier and his Team and one of the most spectacular trimarans to ever hit the water-and the largest sailing foiler in history:


#4--Banque Populaire soon to be launched and featuring all the basic elements of the Fire Arrow Foil System including UptiP ama foils, lifting foil on the daggerboard and rudder t-foil(s). Design by VPLP:

 

Spectacular picture of Gitana 17 followed by Fire Arrow:

 

WOLF daughter of fire arrow: more pictures of the parts partially assembled----

mast,boom and all foils:







Look closely for cockpit drain:


UptiP ama foil:

 

Dumb guy here without the time to go through 2000 replies. I'm just having a hard time understanding the scale. It would be good if you had a human scaled figurine or something of known scale in your pictures. Very hard to get a grasp of the size of the model. Very interesting work I must say. Is it 1:16 or 1:10 or ?

 

The Fire Arrow Test Model uses 3.375"=1' scale. The WOLF concept model uses 1.5"=1'. The Fire Arrow is a nearly exact scale model of a 19.5' sport foiler. The WOLF concept model is an exact scale model of a 15.5' version of Fire Arrow.
I'd be glad to answer any questions.......
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The Fire Arrow Test Model is about 66" long almost 7' wide and 9 ft, tall.
The WOLF concept model is 23'' long and 28" wide.
I repeated a lot of info every few pages so people could more easily find details.
WOLF works with the same foil configuration as Fire Arrow &WOLF, Maserati, Gitana 17 and Banque Populaire are using the exact same principle and nearly the same foil configuration as Fire Arrow.

 

So, is there room for a person on the 19' vessel? Or maybe two? Any payload? Thanks for the great pictures of foils.

 

The design sailing weight of the fullsize Fire Arrow includes three 180lb people and 80lb of gear. The Test Model reflects this weight exactly. Two or three people could comfortably sail the boat and take off in a 5 knot breeze.
WOLF is a smaller version of Fire Arrow and is designed as a singlehander with the capacity to take a second person. Singlehanded she'll take off in a 5 knot breeze-with two people she'll takeoff in 6-7 knots of wind.

 

After so many posts maybe the question is a little out of place but I am going to ask it, why do you say that these are self-righting trimarans?
Another quote, when you talk about taking off at 5, 6 or 7 knots of wind, do you mean the apparent wind?
Thank you very much in advance for your attention.

 

TANSL, when I started this thread in December 2010 I had intended that the boat be a self-righting trimaran. But when I realized how significant the Foil System might be I put that on the back burner.
Another factor is that the model turned out too heavy to allow the ballast that would have been required. The initial target weight was 16.8lb and it is about 21.3lb. The extra weight is ok for testing because it reflects the actual sailing weight.
I'm not good at building one off's very light but I could do the tooling and build a version of the boat from the tooling that would weigh about 12lb leaving plenty of room for "crew" and self-righting ballast.
A self-righting trimaran foiler is definitely possible and the design with high dihedral crossarms and the Two Stage Amas are major elements of reducing the likelihood of capsize as well as facilitating self-righting with the proper ballast.
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NOTE- the stage two portion("curved piece") of the ama is there to support Stage One (ama planing hull) but mainly there to provide buoyancy in a knockdown making it very difficult to capsize the boat.

 

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No, the true wind speed.

 

I understand as self-righting a boat that recovers by itself the initial equilibrium position when, by any means, it is heeled to an angle of 180 degrees. According to that, I do not understand how the ballast could get it in your catamarans.

But, according to the direction of the true wind those figures may be totally insufficient for the takeoff of the trimaran.
Excuse me if my ignorance of any point makes me ask questions with too obvious answers.

 

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The Fire Arrow would automatically right from 90 degrees. The buoyancy in the twostage amas and the oversquare beam should prevent it from going past 90 degrees. Ballast is primarily required for righting from a pitchpole. The Test Model has automatically recovered from a 45 degree pitchpole with no ballast.
The Test Model flew in 5 knots of breeze and I fully expect the fullsize version to do the same thing. A number of foilers have been designed to takeoff in very light air including the Quant 23 foiling keelboat and the Whisper cat among others. It is important so that the customer has the full wind range available to them . Many older foilers would not foil until the true wind was 10-15 knots-modern boats have changed that.

 

Sailing boats, even monohulls, usually have a GZ>0 for heel angles greater than 90 degrees, and even some, for a heel angle of 180 degrees. A boat that did not regain its equilibrium position after a 45-degree list would be totally inadmissible, imo.
I'm sorry but I find it hard to think that a boat, girding with a real wind of 5 knots, will be able to take off. But, of course, you have made calculations and tests that I have not done.
Thank you for your answers.