Trifoiler + Kite

A team of young Frenchmen managed to get a Trifoiler flying with an inflatable Kite wing.
Congratulation to Christophe BALLOIS and Christophe MARTIN.
http://www.flysurf.com/frontblocks/news/PaperView.asp?id_papers=2490&date_start=&date_stop=&gauche=reportdetail

TEAM web site: www.kiteboatspeed.com

HI all.
Have you seen the new vid of this two guys?

https://www.youtube.com/watch?v=TJWCevKdqik

Malric your remenber when you talk to me about the structure… Check that you was right.

This video proves that the concept works but it doen't look fast (25Kts max?)
I am sorry if I mis guided you about the forward beam calcs but I got a 500Kg maximum pulling load from Gilles Durand (0'Paf machine) for a 27m2 inflatabe wing.
The forward beam looks to flexible (up and down) to me and the fulling load appears to be too far back and it is lifting the stern quite a lot. I got the feeling that the trifoiler could pitch pole if a nasty wave catches the main hull nose.
what do you think about the video?

bonjour
je vais le faire en français dans le texte car je n'est pas le vocabulaire technique en anglais.
Il y a quelque chose de tres interessant dans cette video, on voit tres clairement que le foil au vent plonge plus que celui sous le vent. cela me conforte dans l'idée que le kite tire sur la derive opposée plus qu'il ne pousse sur le foil du meme bord. Ils faut donc revoir la conception en fonction de cette nouvelle donnée( profil, largeur du bras… C'est pourquoi en ce qui conserne Dared j'ai dû revoir le bateau qui resemble maintenant a un tripod( je t'enverrai les dessin).

gurval wrote:

HI all.
Have you seen the new vid of this two guys?

https://www.youtube.com/watch?v=TJWCevKdqik

Malric your remenber when you talk to me about the structure… Check that you was right.

You could do it that way.

I certainly don't like the way the beam looks. By discarding the masts, compression strut, and kingpost, they've allowed the beam to deform flat and removed all of its supporting structure. Looks like a waste of a perfectly good TriFoiler to me.

Jonathan

I talked to the pilot/skipper last month and he said that it is very promissing but you need a perfect work between the pilot and the kite man. They have been practicing kite boats together and kite machines for years.
In my discussion, I mentionned the cross beam and he said that they have no problem so far.
They sail between 25 and 30 knots without any problems and they feel that they can sail much faster but they want to practice, learn and sail a bit faster every time. They are also looking for a sponsorship to build a bigger Trifoiler.

The kite is moving in clean air and can in theory be very good. Kites are undergoing a huge developpment at the moment and they should be very efficient and safe in a few years.
I suppose that the kite should be attached directely to the foils to avoid any load on the 'weak' aluminum beam. It is alo very good to be attached very close to the centre of gravity. So it is all about compromise.