Rahul's RC Aircraft and other designs

Building a high flight time RC aircraft, which is easy to carry and fly, made out of easily available materials (foam), and reusing my existing electronics After deliberations, decided on a  simple dihedral (rudder and elevator) tractor of 40" span..  Wing chord was kept at 7" (below that airflow disruption due to low Re number)  It would be flying at low Reynolds numbers (around 80000),accordingly a thin and slightly  under-cambered (4 degree) plate airfoil section was chosen. The dimensions / parameters were calculated based on the design requirements and based on RC aircraft parameters. This aircraft regularly flies + 45 minutes flights on a 1000 mah bty..and is super easy to fly . Many a times after reaching a good altitude & trimming the aircraft I have taken a short break. She can hold bearing even in windy conditions. Just by pointing her into a decent wind and with very minimal ground speed (zero or sometimes negative)she can gain altitude. DIMEN...

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 e...

Pictures and build highlights of a SU 35 The plan printed on a A4 paper. The whole design was based around a 9"  space for prop (mid mounted). With that as the base, the conversion ratio was 1cm on plan was 5.88 cm actual. The total span was 95.1 cm or 37" and the length was 114.6 cm or 45" The above dimensions were drawn on a scrap newspaper and templates cut out or traced directly on 5mm foamboard.  Note the Increased dimensions of the wing and tailplane.  few pictures of the construction The front fuse was made out of 5mm foamboard sides with a eps turtledeck The nose was shaped  out of  eps foam. Below is picture of the elevator mount. The elevator was full moving elevator. It hinges on a 3.5mm CF rotating on a 2.5" al tube. The CF was wrapped around with clear tape to mage a snug fit The wing had a leading edge droop which was reinforced with two chordwise stakes in each wing Note the beveling of th...

This is a forward swept design built in 2015.... l Wanted to explore characteristic of forward swept design for manoeuvrability The design flew marginally. though tip stalls were reduced, it had adverse yaw (probably which could have been due to the increased aileron  width at tips.. a constant cord ailerons might have reduced it). Also there was a lot of drag due to the lower part of the fuse Note the size of the control surfaces I quite liked the paint scheme Flying and being followed by a real Kite

This is profile Mig 15 which I had built quite some time back Wing span 28". It is a tractor and has a profile fuse. The wings are KMF2. The  dimensions were based on the plan, but modified with increase in chord and tailplane area. She flies fast , and is quite responsive to controls. Because of the size orientation is difficult at a distance.