Foiling Trailer sailer

Short answer is yes but not thru the wind range and angles that americas cup or Flying Nikta can do ie mostly beam reaching and below .
Long answer since I do not have access to Gomboc i have done some linear calculations of lift ,righting moment at various speeds with certain assumptions
Primary lifting foil is 144 cm in span 29 cm chord in centre 60 cm with 42 cm tapers to 17 cm chord at the tip
effective area is 3800 cm2
section is a modified Fk131/33 flapped section Hydro balance actuated by a wand
between Reynolds’s 800,000 and 3 million This section has a max CoL greater than 1.5 plus 0.9 for a 33% flap
low drag bucket 0.008 to 1.25 with flap range +/- of 12.5 degrees
aspect ratio of 5.4 so degrades max CoL to 78% ie .97
CoD 0:008 to 0.005 lift to drag ratio 75 to 150 over this range of Reynolds’s numbers 5 to 20 knots
Sailing displacement 1100 kg with 115 kg of crew hiking or on trapezes
lifting foil acts 1.1 m off centreline nominal CoG
So using a CoL of 0.8
6knots. Lift 148 kg Rm in kgm 752
7. 204. 780
8. 267. 810
10. 333. 842
12. 601. 970
14. 819. 1075
16. 1071. 1196
unlike a conventional yacht righting moment increases substantially with speed with associated reduction in displacement and wave making . Moreover LD improves as velocity and Reynolds’s number rise . I am being conservative with my assumed CoL for a flapped foil so lift off will probably occur at 12 knots not 16 which is obviously way above hull speed but entirely inline with a melges 24 power reaching . I expect many years playing with foils both section and size . You will also note that I have not included the rudder T foil contribution of 15 to 20 % nor possible differential rudder AoA
Flying to windward may be possible particularly with a reefed main but sea state will likely intrude .No bets on Best Vmg
 
Productive day we drove 500 km round trip to pickup my carbon Forte 112x 69 mm 9.7 m long 19 kg mast from Spokane . All went well I borrowed my neighbours Martin 242 trailer . I am very pleased with the mast at $4890 US but will need to put a 13 mm harken track on it as well as spreaders sheave boxes gooseneck and headbox . Lots of fiddle carbon bits to make. But such a relief to have it at home. I was considering using the antal/ hall track and reached out to IanA who referred me on to Johnny at hall spars. Unfortunately the base of the section is 45 mm wide which will not fit on my oval mast.
Painting the hull is finished far from perfect but it will do and finished in my weather window .Antiskid will be rolled on later when all the fittings are positioned .
Back to foils and now spars much better than sanding

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Though a little indolent toward the end of summer with 65 th birthday and all I have done a little work. That really means a lot of sanding and painting whilst the weather window is open .
I have removed the 2 top halves of the main foil out of the mould . Thank goodness for poly vinyl alcohol transforms mould release. Also discovered need for 25 gm fibreglass veil to stop air pockets in the weave surface showing .
3 full length and width 400 gm uni carbon then 7 more layers in step down length 100 mm wide 400 gm uni at 90 degrees 3 layers of 100 gm biaxial carbon 1 layer of 200 gm carbon cloth. 100 gm and 25 gm fibreglass cloth .
bottom halves to come then shearweb foam and making a Kevlar hinge in flexible epoxy to fit in the rebate in the lower mould see tape at 33 % chord from trailing edge . Plus spreaders . I did get titanium rod and tube from china for masthead axles and spreader compression tubes which will double as tangs for the dynema rigging not as nice as Julian’s but should do .

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