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Archive for May, 2019
Posted by Knoll53 | May 07, 2019 @ 10:16 AM | 1,110 Views
I fly exclusively slope. So the likihood that I ever start my Ka-8 Flair kit is low. That scale plane will turn with it's scale aileron, but will not be anywhere near maneuverable enough to be a fun slope ship at my local rotor filled, paraglider infested coastal flying site. I am a scratch designer/builder so making a few mods is a given. Here is my short list. I am not a scale purist.

Dihedral
­Maintain the stock dihedral. this will not hurt the roll rate enough and the plane just looks better with dihedral. Rudder only turns are possible.

Tow release
­Although I do not plan on aerotowing, install the nose hardware for a vintage loop and pin tow release.

Flaps
­Modify to be fully aerobatic with full span aileron by adding full flaps. Flaps can be used for landing. Possibly make flaps stop at 20% of the half span. this would provide a 80% long aileron and a plenty big landing flap which is not needed for landing since it has spoilers. I am assuming that the Quabec 15% thick, 3 % camber section and 5% camber at tip will be very slow.

Spar
­Beef up wing for high loading. Add carbon spar cap. Top spar cap double the bottom spar cap. schedule based on moment loads. shear webs based on shear loads. wrap joiner with kevlar.

Scale details
­Looks like the FS steel frame fuse is built from 1" tubing or smaller. Replace the kit longerons with hardwood dowels and use MGS epoxy fillets. Also the FS was a full space frame without the giant lite ply formers. Maybe use the kit's formers just as a jig for your hardwood dowels, then after fully braced, cut the formers out. the manufacturer says that the longerons are spruce and you can see from FS photos that they provide a sharp crease in the covering.
For the first flight, no exterior paint or scale detailing, such as instrument panel, seat.
­Paint the fuse framework with heavy sandable filler to fully fill the grain then glossy paint to resemble steel tube.
­Build the wheel and skid to scale and make sandproof.