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FeiJi's blog
Posted by FeiJi | Mar 15, 2015 @ 03:04 AM | 3,252 Views
Here is a neat little poster I got here in china in a bookstore of the P51 B.
Unfortunately it is printed on brown paper so hard to read but I took some closeups for you aficionados.
Posted by FeiJi | Feb 19, 2015 @ 08:22 PM | 3,282 Views
Getting 15 minute+ flights from my 40" wing.
AUW is 750 grams but 120 of that is dead weight in the nose under the battery. So I could replace that with another 2200 3s lipo and get 30+ minute flights but that would tax my neck.
Motor I think is 1800kv, 40amp esc 7x5 prop.
Spars are fiberglass fishing pole sections, very light and strong.
Wing was then covered with laminate film. Very strong and flies very well.
Posted by FeiJi | Feb 05, 2015 @ 01:56 AM | 3,672 Views
Just some noodling around with my new BoneYard 6 40" EPP wing with big tube spars. No fins. No expo - I like my sticks touchy. Not a good place to fly, too many obstacles.
40 Inch EPP Wing with Big Tube Spars - Noodling Around the Sky (4 min 59 sec)

Posted by FeiJi | Jan 17, 2015 @ 08:29 PM | 3,315 Views
My first hatcam finally died, rip, and I bought another keychain camera (dont know which one) last year but the battery died very quickly.
So made it into a hat cam with external battery.
Just opened up the case, unsoldered the original battery leads, soldered in it's place a female JST plug , hotglued the wires to the circuit board so they won't pull out, and away we go.
I like the external battery because I can user bigger mAh lipo for long life between charges.
The battery is under the cap held in the liner by the spring clip.
Bolted and zip-tied camera to the hat.
I had to get rid of my MGB but kept the hat. Both have seen better days.
Posted by FeiJi | Jan 03, 2015 @ 12:26 AM | 1,759 Views
Wow, still tail heavy but I can tell it's got great glide. Add a little more nose weight, and clean up the end of the wings (one still has some extra length of tube spar sticking out) - guess I should be surprised it flew at all. Now 700 grams so will probably end up at 750 but that will handle wind well and it still will glide great
(Optimist.)
Update: 1/11/2015 - another 50 grams did the trick - it flies beautifully now. Just have to get my camerawoman back. Love flying finless.
There is so little sweep that it is basically just a flying plank. CG has to be spot on. I knew that.


BoneYard 6 EPP Flying Wing Maiden (0 min 34 sec)

Posted by FeiJi | Nov 17, 2014 @ 08:38 PM | 2,176 Views
AUW 615 grams. About 400 sq inches area. 1800 kv motor, 40amp ESC, 2200 3s lipo, Radio is inside wing. Just don't have camera anymore for maiden so will have to get someone to video or attach my camera to my tx somehow.

First flight didn't go well as too tail heavy. Same story with first one I built as it has low sweep and needs forward cg - almost as much as staightwing tailless plane.
I will add couple ounces and it should be fine. This size wing carries more weight easily and doesnt effect flight time much. I expect to hit 20 minute flights with this battery as my last wing of this configuration hit 18 minutes on an 1800mah lipo..
The truth is in the testing I guess.
Posted by FeiJi | Nov 12, 2014 @ 06:06 PM | 4,190 Views
Finished the airframe and ready to add controls and electronic stuff. Weighs 260 grams without any equipment. About 400 sq inches and should be final AUW of 600 grams. This is my BoneYard 6 wing. This will be finless like my other wings.
Posted by FeiJi | Nov 09, 2014 @ 04:57 AM | 2,607 Views
I gave away my last 40" wing when I moved and enjoyed flying it so much I had to build another. Reinforced this one with carbon fishing pole sections - so strong I can't bend the wing and I haven't even laminated it yet. With the big tubes (which add very little weight) and little flex, this feels more like a real airplane wing. This one should last a few years.
Posted by FeiJi | Oct 20, 2014 @ 07:10 PM | 2,147 Views
I needed to refurbish my year and half old wing center section and decided to use two sections of lightweight fiberglass fishing pole to shore up the center section. Wow, amazed at how strong it is with them hotglued in and I havent even laminated the center section yet. Do believe it would be plenty strong enough without the laminate. Pictures shows one rod where I left out foam so that I could sink my ESC and radio into the fuse, the other is further back under the foam. Much better than thin carbon fiber rods or flats or barbeque spits.
Posted by FeiJi | Sep 05, 2014 @ 03:35 AM | 3,122 Views
Well it's together. Tail is off by 1/8 inch, wing too far back by 3/16, got some wrinkles in the wing laminate because I dont have a heat gun. But it is very strong. Surprised it came out as well as it did with just a clothes iron.
Wish I had an ugly contest to enter it in.
AUW is 145 grams but may need a little ballast. Could easily have left out the carbon spars as the laminate makes the wing plenty strong enough. I glided in on my bed and swung it around by the peg. The vertical stab should hold up as I doubled the laminate there.
Just have to install servos.
Not too bad considering no instructions. I suppose I could do another one now that I know how it probably should be build.
I dont expect it to be an amazing flyer but hopefully it will get me a little further along learning how to fly dlgs. I expect it will fly better than my fake alula.
Probably wont get to maiden till nxt week so I can just anticipate good things happening.
Posted by FeiJi | Aug 30, 2014 @ 12:41 AM | 2,906 Views
I am in a temporary apartment and don't have any real tools or workspace but decided to start putting my glider together anyway seeing as how it's so cheap, I can afford to make some mistakes - and I did.

I have no instructions but with a little thinking about it, the parts just kind of put themselves together. The fuselage was a no brainer and the pieces fit great.

I have no jig but the wing went together pretty easily though I messed up the LE and decided to remedy it with a piece of balsa I had to cut to add to the LE, and then to leave off the wing sheeting on the LE. The wing will still be very strong because I put in a carbon fiber slat wingspar and I am going to be using laminating film to cover.
Just need to do some sanding.

Have all major components assembled and comes out to about 110 grams without electronics.

Now if they had only sent me the other wing.
Posted by FeiJi | Aug 28, 2014 @ 12:56 AM | 3,841 Views
(Please note that I am working in china so do not know if or how this may be available in US.)
I got this 160rmb dlg balsa kit in china on taobao.com with no instructions.
Think I have figured out where all the parts go from looking at the picture. Just not sure how far the fiberglass boom goes inside the fuselage. i can figure out the cg. Will use copy shop laminate to cover I think. Can hardly go wrong for the price.
Pretty complete kit, even a couple magnets for the hatch.

Have started building the fuselage, going together nicely.
Posted by FeiJi | Jul 26, 2014 @ 07:30 AM | 3,513 Views
Ha ha. Not really. Black epp looks like asphalt though.
I'm in china and got this Alula like plane kit for 80rmb ($13) from www.taobao.com.
I have been flying about 4 years but never done a glider and I moved to a new part of china and didnt have anything with me except my transmitter and a receiver. So ordered this kit, a couple servos and lipo batteries and stuck this glider together with some shoe glue and hot glue. Made hinges out of vinyl notebook. I used shoe contact cement to glue in spars as it stays flexible but holds well and will not shatter when flexing or hit. I have doinked this glider on its nose many times and it just bounces. The spars in the fuse are definitely necessary and functional

Went together in about 3 hours. Didnt even cover the wing or fuse. Mounted the rx upside down to protect the wires and had to put some coins under the battery for counterweight.
Boy what a kick this glider is. I maidened it yesterday. Went to the football field here and after a couple of glide tests, sidearmed it up. Beautiful.
I can only throw it about 15 meters high but spent another hour today and I was sweated out and sore. What a thrill this flatland gliding thing is.
Don't know what it weighs but feels like nothing. 6 gram servos, no covering. Put single spars in top of wing and the balsa elevons are doing great.
Yesterday the grass was wet and the epp was soaking up the water so plane got heavier but still flew.
Did some catches which is surprisingly easy.

Always something new to learn in the rc world.
Posted by FeiJi | Jun 05, 2014 @ 07:22 PM | 3,813 Views
I was flying my P51 when one of the landing gear fell off into the woods never to be found. So bent a bike spoke , added a spoked wheel and now have a beautiful replacement. Actually have two right wheels now.
Posted by FeiJi | Apr 21, 2014 @ 03:38 AM | 3,815 Views
Just flew 16 minutes and 45 seconds on an 1800mah battery in my 40 inch epp wing. Not even a new battery. That is with 2 ounces of steel ballast. Also passed 60 hours total air time. Not much time to show for 3 years of flying but I have lots of video and it has been memorable. Happy Easter (day after).
Posted by FeiJi | Mar 29, 2014 @ 08:28 PM | 4,316 Views
Got my 40" BoneYard 5 finless epp wing out today and ran 4 batteries through it. Great fun. Got 10 to 12 minute flights on each 1800 mah lipo in 10 mph wind. Flying about 50% throttle most of the time but pretty much unlimited loops and rolls, just used altitude to do them. This wing is pretty interesting to fly as it flies straight when at speed but waggles like a kite when you do a hammerhead or slow turn up wind. I kind of like that because it remains controllable but has a touch of unpredictability at times - something most fliers don't like but it keeps this wing interesting to fly. I suppose I could put fins on it but then I would get bored with it.
Wing is about 400sqin, AUW 695 grams, (24.5 ounces), 1800kv motor, 1800mah lipo, 40amp esc, 7*5 prop. I did get a 15.5 minute flight one time on a new battery.
It has a couple ounce metal plate in the nose that I could get rid of with a 2200mah lipo and then I might get some real airtime. But Im too cheap to buy them.

Going to get my Ugly Plank out next and take the wing extensions off it cause I like the way it rolls with shorter wings. Plan to build a new Ugly Plank soon.
Posted by FeiJi | Dec 24, 2013 @ 09:27 PM | 4,258 Views
My first little trainer had only a single axis of movement, I guess yaw. So I decided to add another axis so now it has pitch movement. It isn't totally realistic as the higher it gets, the less power it takes to fly so you have to back off the throttle or it will just peg the lever to the stop. It really needs a way to control the counterweight so that the weight on the rear of the lever decreases a bit as the motor side of the lever rises. But that is too much work for me. It is kind of fun now in that it takes a really light touch and you have to jockey both sticks to get it to fly level.
The only improvement I think I will make is to put the motor on a little gimbal so that the prop and motor stay level.
RC Flight Trainer II - Two Axis Movement (2 min 51 sec)

Posted by FeiJi | Nov 22, 2013 @ 01:47 AM | 4,310 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 @ 03:31 AM | 4,587 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 @ 12:35 AM | 5,707 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)