The final plan for PLAIN SAILOR is below. Right click to save it. Flying the prototype revealed a weak point at the fin to fuselage joint. This is because the main strength at that point comes from one side of the fuselage, that is, 5mm of 1/16" balsa!
So, I cut the fuselage at the stab and trimmed the fin down, as it was too big. After re-attaching the tail feathers, the glider was much better behaved. I guess the moment arm of the prototype was too long. Compared to the prototype, the overall length (not including ballast) of Plain Sailor is 18".
Unfortunately, I do not have an indoor venue to fly in, but outdoors in the calm evening air I was getting flights of 25 to 30s. I'm sure that could be improved on with more work on the launch and transition trimming. However, this model was not designed purely for duration, but also for the other "tasks" that make up the one-sheet indoor competition, including longest glide and spot landings.
I used a small pea of blu tack on the left wing and a teeny bit of left rudder to get it flying conventional right - left. Take those trims off and it will go straight and level, since there is no stab tilt.
To make it suitable for outdoor, I would suggest gluing a thread on the LE with CA, increasing the dihedral to 2" under each tip and finishing it with 2 coats of sanding sealer with very fine sandpaper in between them. With its light wing loading it could easily fly away in thermal lift. Higher launches would require a decalage setting closer to 0-0, but as has been discussed before, that can introduce inconsistency in way the glider recovers at the top of the launch.
If you build this simple glider, please let me know how you get on.
1 comment:
umm i have a question. have you ever done a sort of sling shot balsa wood glider? i really need help or tips or anything that may help. please. thanks
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