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Archive for November, 2013
Posted by FeiJi | Nov 22, 2013 @ 02:47 AM | 6,182 Views
I found that adding large diameter rods to the leading edge makes a significant difference in flying behavior, more stable, seemingly faster and definitely stronger. Also added a little cover for the electronics as I will be landing in the snow for a while now.
Posted by FeiJi | Nov 20, 2013 @ 04:31 AM | 6,427 Views
Here are a couple of more flights with my open close canard wing. Both resulted in hard landings but I did transition from open wing to close wing and flew around a bit. Also figured out why I am hard landing. When I play with the pot on my radio to open the wing back up I accidentally shut the throttle off. Oh, well, it works and when I get better weather I will learn to fly it more smoothly. This wing is pretty fast as only doing 60% throttle with 1800kv motor and a fat 7*5 prop. Imagine it will really scram with a 2600kv. Not bad for a flat plate. Added a couple of fishing pole supports to leading edges which added another ounce and thought it would hurt performance but I think it flies faster and smoother than when the body was flexing without them.
Swing Wing Flight 2 (3 min 44 sec)

Posted by FeiJi | Nov 16, 2013 @ 01:35 AM | 7,742 Views
I have been working on this delta with a movable forewing or canard. I have had successful flights with it rotated out and rotated in but only one time did I rotate it out and in during flight successfully. The final rotate in led to spiral into ground. I think I have figured out what leads to the spiral when I rotate the wing in and when I rebuild the wing will try out my theories. The cg shifts a little bit after rotation but easily corrected with a little bit of elevon up or down. With wing out it is a little high alpha and with wing in a little low alfpha.

The video shows take-off with wing out, then I did rotate it in successfully but it is impossible to see in the video,then rotated it out again then when I rotated it in the second time it led to death spiral.

Plane does land softer with canard out and comes in pretty hot when it is rotated in.

My final flight yesterday ended up in tree and I had to buy a fishing pole to get it down.

My thinking about the transition behavior is this: when I slowly transition the wing in or out with the radio pot, it seems to work ok but if I use a radio switch to transition - it leads to some serious flight instability. So will use my radio pot to gradually transition the wing when I get it flying again. Also, perhaps if I go a little high alpha before transitioning the wing in, perhaps that will prevent the spiral in. Also, noted in the video that I throttled back during transition - maybe some problem there.

Anyway, kind of interesting. Will post another video when I get it sorted out which may be a while since we are getting lots of snow now.
Swing Wing Canard Foam Delta (1 min 9 sec)

Posted by FeiJi | Nov 01, 2013 @ 08:13 AM | 5,966 Views
Just doing some flying around. Finally resolved why takeoffs and slow flying would stall. I had rounded the leading edge of the forward half of the wing with wooden dowls but left the rear halfs flat - this is a 9mm epp flatplate. On takeoff the delta would roll left then right terribly until I got some speed up. So I rounded the rear half leading edges with dowls and problem went away. Now this is a really fun and easy to fly flatplate.
Also I cut the elevons down in an attempt to solve the problem but it wasn't due to too large elevons and now wish I hadn't cut them down.
I plan to make a slightly larger X45 like this but with an airfoil.

X45 EPP Scratchbuilt Delta Wing flight (3 min 29 sec)