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Archive for October, 2012
Posted by FeiJi | Oct 18, 2012 @ 05:10 AM | 5,062 Views
I made a few rolls and loops with my 1 meter Bobtail Plank and edited at double speed so I wouldn't get bored rewatching videos of flying my planes.
Watching the plane at a faster speed makes flight characteristics and imperfections pretty apparent, gets me through the video faster and it is kind of beautiful in some weird way.

1 Meter EPP Bobtail Plank with Few Rolls and Loops at 200% Speed (0 min 0 sec)

Posted by FeiJi | Oct 13, 2012 @ 03:28 AM | 5,050 Views
After a number of false starts my wing is finally flying. I got a 10 minute flight on a 1500kv motor with 7*6 prop and 1100mah lipo. The front fuse is mostly a piece of bamboo plywood I cut from a clipboard. AUW is 600 grams. It's tough getting the cg to 10% which is only a few centimeters from the LE. Thanks to Averan for his help.

Added first video of few loops and rolls.
Second video was of first flights.
I like this plane so much that I am going to strengthen and steamline the fuse. Will use some graphite fishing pole sections inside few layers of 9mm epp foam, wrap with strapping tape, then wrapped with colored tape then laminated. Then affix wings with couple of bamboo chopsticks. Then make a wood motor mount and use a faster motor. Will also move forward a larger tail.

1 Meter Bobtail Plank A Few Rolls and Loops (0 min 0 sec)
BobTail Plank EPP Foam Wing (1 min 38 sec)
...Continue Reading
Posted by FeiJi | Oct 04, 2012 @ 07:08 AM | 5,525 Views
I wanted to make something besides a swept back wing so was looking at Bill Evans Scimitar wings and decided to try one. I can build a wing in 3 or 4 hours but the addition of a fuselage requires another 3 or 4 hours. I like the wings better because they are pretty crash proof but when this plane noses in, something is going to break.
Bobtail Scimitar EPP Plane (4 min 37 sec)

Mine is quite ugly, quite evolved or devolved and took a while for me to figure out why it wouldn't fly.
My first one was finless but had the rear fuselage angled up, not realizing that that would act just like up elevator and make the plane into an infinite looper. Then I cut that off and angled it down which of course had the opposite effect and it would try to fly but as soon as it got level it would make an instant dive. Also since I cut off most of the tail I had more vertical face in front of the CG so the plane would take off then promptly switch ends.
Finally I added a tail but was too tail heavy so it just wallowed around in the air.
I also cut the elevons shorter because someone told me they were too much. I think I will put them back full length now that it flies.
In the end I got enough weight into the nose that it flew and I like the way it flies and looks in the air so I am going to build another one that is lighter, with thinner wings, a higher kv motor and shorter tail. It should really scoot.

(Photo #1) My first attempt probably would have flown fine without the tail...Continue Reading