This is my first attempt towards a light weight plane. Built it with 3mm depron. Have a combination of kf airfoil and conventional. Steps till 50% but has a symmetrical airfoil. Dint worry much about the canopy, wanted to keep as light as possible. All electronics are held by velcro. Have a battery in the back to adjust cg. Waiting for a motor from VK singh.
Airframe alone is 70grams. Rest all electronics 
Wingspan 25inch
AUW:150grams
Battery: 350mah 2cell
2x5g Hextronik servos, 1 mixer

looks good!!!

some more pics pls!!!!!!

all the best for maiden!!!!

No cuts and grooves on this one?

All the best for maiden.

When are you planning for maiden?

Quote from: rajathv8 on December 27, 2010, 02:17:17 PM
No cuts and grooves on this one?

No..have barely used any glue..

Quote from: R C on December 27, 2010, 02:27:29 PM
All the best for maiden.

When are you planning for maiden?

Thanks..Probably next week..

We had maiden today. The motor is too good. I changed the setup to three cells and I could do unlimited verticals. The video has not come properly as the plane has gone out of sight most of the time. Will post it next time.
And also I had to land this pretty early. With full throttle and with quite a good speed it flies very well. If I tried reducing the throttle to near zero, I would loose control as it went into spiral yaws!! Never seen this in any of the planes before. As i dint have rudder had to push the throttle and gain height and had to control it with elevens alone. Luckily I dint crash but had to stop flying until I could fix this issue 
Most of the times it happened during a turn or near zero throttle. Is this adverse yaw which is causing this or lack of winglets?

it is the spanwise flow, you can add a wing fence, advantage ? easy build, less tall fence would do. δ washes out due flexure add a little wash in if possible.

ah! thanks for 11 of'em kind of you

Thanks augustine. Any idea on where exactly the wing fence should be? My wingspan is around 25inch

spanwise flow doesn't start until 50% of the semi span from the fuselage, a fence at at about an inch towards the wing tip from your aileron servo line should be enough, fence should end an inch from the aileron, if you can keep the top end sharp, it will energize the aileron as well, all parts of the fence behind the CG line will additionally give you directional stability. esp at high angles of attack. Boundary layer is 1/20th of an inch to 1/2 inch thick depending on whether it is laminar or turbulent. a dot less than 1/2 inch high will do the trick i guess.

Waiting to see the modified flight 

ah one other thing, fence only on the top surface. 

Added wingfence and fuse. Ready for testflight

Added both wingfence and winglets. After adding winglets its more stable now, but the issue with spiral instability is not resolved yet 
I do a throttle cut off after gaining height and it just spins, no idea what is happening. I will upload the video shortly.

reducing the vertical stabilizer area will help

Quote from: royrahul on February 22, 2011, 11:48:58 AM
reducing the vertical stabilizer area will help

!! Decrease!
Add Fin half the size of the Rudder to both of the Wing Tips..

Your vertical stab is too close to the CG to be effective.

Have added the winglets recently and reduced the rudder size too. Last weekend it flew wonderfully at high speed. But was unable to do glide with throttle cut as it simply yaws continuously.
Somehow havent been able to take a video, will do that next time. Last attempt to fix this will be adding a rudder  

At last was able to take a video from my Sunglass Cam 


Video quality is bad, till now it used to be good in sunlight. It was very cloudy today.

My sunglass cam setup with wideangle lens 

Somehow need to work on correct inclination to get it focused

Hey foamy... Where did you get that Wideangle lens from ? I have this keychain cam too... its looks like a nice idea...

@dealextreme

Ashutosh was able to shoot a high quality video with his digicam finally 

  Its Gliding beautifully. I think it will make do without the middle vertical Stab in this case.

HI

That is a nice and simple build foamybuilder. Is you problem on throttle cut resolved. If yes what did you do? I think dutch oscillation might have been the culprit.

Regards
Ankur Kaul