Hope to maiden this over the weekend !

Here's my KF2 Delta. Specs are:

1. Span - 30 in.
2. Chord (root) - 18 in.
3. Chord ( tip) - 6 in.
4. Airfoil - 50% KF 2.
5. Elevons - 2 x 1 x 11.5 in - 2 pieces.
6. Weight as of now - 80 g (includes a teak wood beading for leading edge, yet to download the pics)
7. Wing area - 2.5 sft

Started with drawing the 'plan' on the floor to see how it would look.Had a few pieces of 12mm thermocol and put this together. The build itself is simple. Did a glide test after adding a AA cell to the nose for CG. The glide is flat and stable. Yet to see how the CG will shift after adding the gear and whether I'd be able to manage the CG within the delta, without adding an extended nose.

Hope you like the pics......

......and wish you all a fantastic year ahead !

-b

  pics....

The dimensions and ratios are quite similar to Sift Like KESL made by Sarad ('R C') and me. It should fly. Add Vert Fins at both  the wing tips if you need more stability.

what material is this.........

Quote from: kplkum on December 31, 2010, 12:33:22 PM
what material is this.........

Its normal thermocoal, he has teakwood beedings in the leading edge and carbonfibre for the span

Best of luck for the maiden

Quote from: foamybuilder on December 31, 2010, 08:24:50 PM
.... he has teakwood beedings in the leading edge and....

Sounds exotic!! any reason of choosing over CF rods ?

hi bmblb

I had a few questions,
1. why δ, δ gives good lateral (roll) stability but spanwise flow reduces lift, the rate of this reduction increases with α (I am sure you have a practical reason for it, could you share ?), δ planform traditionally has been a supersonic planform.
2. 2 deg dihedral/ high wing would give you necessary lateral stability.
3. straight wing with a slight washout will give you reduction in weight, longer glide due high Lift/Drag ratio and better stall characteristics.

δ, looks great, I am flying one, Roll rate ? awesome. δ is a killer   

all the best 

Guys.....sorry. Have been a bit tied up and hence have'nt been able to respond.

The material is 12 thermocol. Airfoil is KFm2

Using teakwood beading as its cheaper  And will add winglets at the tips + a larger Vert stab.

Havent been able to maiden, thanks to HK

Quote from: augustinev on January 01, 2011, 02:29:16 PM
hi bmblb

I had a few questions,
1. why δ, δ gives good lateral (roll) stability but spanwise flow reduces lift, the rate of this reduction increases with α (I am sure you have a practical reason for it, could you share ?), δ planform traditionally has been a supersonic planform.
2. 2 deg dihedral/ high wing would give you necessary lateral stability.
3. straight wing with a slight washout will give you reduction in weight, longer glide due high Lift/Drag ratio and better stall characteristics.

δ, looks great, I am flying one, Roll rate ? awesome. δ is a killer   

all the best 

augustinev

I had to read your post a couple of times to understand it. But I did learn a few things in the process.
Choice of Delta was largely because I needed a new build experience - AND, was hoping to learn the ropes of flying with elevons.

Agree with you on all counts there w.r.t roll rate,reduced lift etc. All my planes so far have been slow (and sedate and have helped me learn to fly). Thought I'd try out a more 'ambitious' project. Fact is I am completely blown by the KF aifoils' perfrmance and know that a conventional high/mid/low winger would work. I am curious to find out how a delta(or chevron, as I later learnt) behaves with KF2.....glide is encouraging.

BTW, the WL is likely to be in the range of 6-6.5oz/sft......not sure if this is ok......but lets find out.

see the forum a couple of them built Kline Fogelman m2, 3 i think? awesome, did a few spads with coro..mmm . Chevron's trailing edge sweep is same as leading edge, whereas δ has more or less straight trailing edge, chevron flexes easily and it the process it tip stall. Low speed behavior of a δ is unpredictable because it doesn't really stall. it losses speed rapidly due to sudden increase in drag, be sure to add some mid wing fence. don't count on that WL, it is going to go higher than expected (Practical experience), higher thrust motor won't hurt. Below the min drag speed, the drag will continue to increase and you will have to increase throttle to decrease speed (However paradoxical it may sound) see total drag curve image. all the best. You want a beast ?  you got it 

this is getting interesting.....

augustinev......could you share some pics of your delta?