Flying Wing -KF-40"

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This is a 40" span KF flying wing

Airfoil is KF2, 50% top and 7.5%
Root Cord - 25cm, Tip Cord - 25cm , sweep distance -25cm
CG -17.5 cm from wing leading edge
It has one CF spaning the whole wing.. Latter version had 2 X 3mm spars
Bty- 1000mah 3S
2228, 1400kv
7X5 prop
AUW with cam - 465gms






I did not quite believe in the advantages of a KF airfoil .. but this aircraft flies (glide ratio, and sink rate)  much better than a flat plate wing... and the difference is quite noticeable ..

She is a great flyer.. good climb, good glide.. very stable, once trimmed can fly in a thermal with  minimal inputs. Stalls are predictable

A video from a on-board cam
https://www.youtube.com/watch?v=3VPjojkbF04

The first aircraft broke apart in mid flight when trying to pull up after a high speed pass..  as the design was very good was tempted , and built a second aircraft  on the same lines .. more strengthened (with 2 X 3mm CF  spars in the wing.. the earlier plane had 1 cf spar)

A picture of the new wing .. the smaller Orange one




A flight video is here
https://www.youtube.com/watch?v=E-fVJkKyCvY



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