Hi Hernan, Yes, I do use the NACA0018 foil shape. I will be sailing Voyager 2.5 a bit more in the ocean to learn as much as I can. I need to apply what I learn to Voyage 3.0 to maximise its reliability before heading to the ocean.

Thank you Hernan. I'm using Self-Trimming Wing Sails. They are not good when running dead downwind. They present very little surface area when running downwind compared to other sails. I restrict the downwind sailing angles to approximately 20 degrees either side of dead-downwind. The trim tab on the self-trimming wing sail is controlled using a Bluetooth radio link to main controller computer in the equipment bay on the hull. I believe you have seen the main blog located here: thevoyagerseries.blogspot.com/

@@JohnSemmens1 Amazing... so you have 2 dead bands, upwind +/- 30 degrees, plus -/+ 20 degrees downwind, understood. How are you measuring the wind direction? are you using an ultrasonic windvane? I was not able to see any article on your blogpost, which btw is amazing.

Thanks Hernan, Yes, the max upwind and downwind angles are stored as configuration items. For the smaller boat I restrict its upwind sailing to +/-35 degrees to keep it moving well. I estimate the wind direction using the wing angle of the self-trimming wing sail. I then apply some approximate corrections to compensate for the trim tab, which causes the wing to have an angle of attack, I also apply an approximate correction for the apparent wind angle change due to boat speed. The wing angle angle is measured using magnetic sensor (mpu9250) and a magnetic disk. Its discussed here: thevoyagerseries.blogspot.com/2019/07/wingsail-angle-sensor.html . Although a bit out of date now.

Hi Peter, Sorry,I had not seen your comment. I originally studied your website a few years ago when I was researching self-trimming wingsails, and it was quite valuable to highlight what was possible. I originally started to design a 3D printed cam and lever type control system for my models. But my background is electronics, so I swapped to an electronic solution, using Bluetooth to communicate between the main controller computer and the wingsail servo.

@@JohnSemmens1 Thanks for answering - The beauty of these self trimming wingsails is that the boat goes well upwind and does not get blown backwards - because the L/D ratio of the wing is so good.

The company Saildrone has done a great job refining this type of sail... www.saildrone.com/

@@JohnSemmens1 I see your model testing. Are you planing a full size version?

@@robertpatterson4732 No, not planning a full size boat. This is a prototype at about 1.2 metres long. The next boat will be about 2 metres long intended for ocean voyages.

@@JohnSemmens1 Thanks again for taking the time to share what you are doing.

Chris Fredriksson I used the ABS/Acetone to glue the sections together. Something to seal the hull would be good, because it does slowly leak, but it doesn't affect short runs around the lake.

John Semmens Ah cool! Well I've been thinking of doing something similar myself, both earlier but even more so now when I saw your video, but I'm thinking of how to seal the hull. Perhaps some filler and then spraypaint and clear coat? Should fill in the small gaps in the 3D printed plastic, give color and then seal it, what do you think? Would love to see more of this boat or any other projects like this if you have any =)