New Trimaran Foilers

Update from Len Surtees from 25th November.

"After long discussion with my friend, structural yacht engineer he suggests be for modifying fwd foils, further testing needs to be done.
To minimize breaching of fwd foils I am thinking about a simple mechanism that can change rudder elevator pitch while out on windward float. Also a younger crew member can move their weight fwd quickly to help keep bows rising to help keep boat level.
At first opportunity I will again return to Wangi for further testing ."

 

Update from Len Surtees 27th November.
"Tried to get short foiling video on web site this afternoon, we ran out of time, problems with his computer copying my video on my computer as they are different formats, will try again this Friday morning.
Friday i buy material to build lightweight float bench seats 1.8mtrs long and weigh 5 kg each, they can be stowed in cockpit when trailering and clip onto outer floats so can comfortably sit and slide as need be to help balance foiling = easy.
Have attached short article on my forward foils that you can post on web, thanks.
I have two others that can be posted over the weekend, 1/ Why swing beams and 2/ long lasting beam pivot pins and bearings."
With separate article here:
"Why my two stage differential foils on my innovative STING 600 Foiling Trimaran are not twisted like a propeller.

I have been asked if they are similar but the short answer is no.

The propeller, whether in air or water has the same problems due to the hub rotating at a much lesser speed then the tip. To overcome this problem and maximise thrust the pitch is variable. The blade angle of attack at the hub is high and gradually twisting, reducing to a shallow angle of attack at the tip. This maintains a constant angle of pitch attack relative to the "rotating speed" and gives an even thrust.

My Two Stage Differential lifting foil wing has two distinct angles of attack. They are not twisted like a propeller. The outer wing (or tip ) is set at a different angle of attack ( to the root wing ) which doesn't change along the length of the wing tip. The design logic is the outer wing tip is designed to partly come out of the water after lifting boat clear which then reduces the overall angle of attack to allow the root wing lesser angle of attack to enhance forward speed. I have successfully lifted the STING 600 out of the water ( flying ) with no breakages and now making minor adjustments to improve overall performance.

The whole concept is to make foiling simpler, not having to muck about making continual adjustments to forward foils. The rudder elevator plays an important role in pitch trim coupled with forward foils but i am not going into detail at this moment.

The super fast, super light weight composite machines, super agile elite athletes , with super deep pockets do not need to worry about my KISS foiler, haha. The STING 600 is an entry, budget elementary simple foiler. This is not a racing foiling machine as it is too heavy for that but rather a chance for the average sailor to experience the absolute THRILL of FLYING. Every one who has sailed on my STING 600 have all been over 60 years old.

Looking forward to hearing about talented young sailors getting the best out of this Two in One design STING 600.

Len Surtees designer STING 600 sports/foiling trailer Trimaran. sting600.net"

 

A new Astus 22.5 foiling trimaran - not sure if anyone has noticed this:

Astus 22 https://www.astusboats.com/sailboat-astus-22.html

I went out on an Astus 20.5 a few weekends ago and it seemed a lot better made than the 16.5 I tested last year in France.

It will be interesting to see some video of this hopefully but Astus do appear to be pretty dreadful at getting any good marketing videos.

 

Unfortunately, the "Nautic 2020" exhibition in Paris has been cancelled (cause Covid), for which the new Astus 22 presentation was planned. The Federation of nautical industrials are trying to set up a substitute in March , the "Virtual Nautic". Astus not yet registrated, but one can suppose they will post pictures and videos for this (virtual) event.
Virtual Nautic - 12 et 13 mars 2021 https://www.fin.fr/virtual-nautic

 

For anyone interested, there is an update on the Sting 600 foiler project.

I've put these pics and further info on the Small trimarans under 20' thread.

Basically it will be in the UK for April hopefully and will then be getting some regular hard sailing to iron out the kinks and hopefully provide a huge amount of fun!

 

The Adventure 600 has finally arrived in the UK having suffered some damage in transit unfortunately, but nothing critical thankfully!

I'm just sorting some quick updates to the trailer and rigging so I can take it down to it's permanent boat park at Calshot and hopefully will be out on the water this weekend if things go to plan.

 

In the meantime, I'm not if everyone has come across this new Vortex Pod Racer:

Home Page - Vortex https://vortexpodracer.com