Hound 34"- Build log

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A fast rc aircraft for flying for windy days (not a floater). Main design aspects, around 36" span, Plank Flying Wing, like funjet (not swept back and hence no twist), low drag, higher wing loading,  high power /wt, symmetrical airfoil.

Material blue foam / insulation board / XPS..  Airfoil NACA0009, thickness 9%. , hotwired
the final dimensions are
1. Span =  880mm / 34.6"
2. Root cord = 250mm / 9.8"
3. Tip Cord = 150mm / 5.9"
4. Sweep = 30mm / 1.2"
CG @ 15% = 44.5mm / 1.75"
Wing area = 17.52 sqdm / 271.6 sqinch / 1.88 sqft

The wing was hotwired out of blue xps.
The fuse is also blue xps, hollowed at some places , with some strengthening

Initially I was planning to have a CF sparred wing covered with monokote ..  hence, according to the earlier plan , the wing  has CF spars  and a CF tow, while the fuse has balsa and an aluminium channel embedded for strength.
Latter on, in midst of the construction, decided to cover the whole aircraft with fiberglass cloth.. and hence the whole wing and bottom fuse was covered with one layer of 100gsm fiber glass.. this was a hand layup.. because of having both the initial spars and AL channel + the fiberglass covering the thing is over-engineered for strength, and it could have been lighter by @ 50gms

motor Turnigy 2826-6-2200kv (though this is what is written on the motor, its dimensions are 2216) , 50A esc (that is what I have currently), 3S 1500mAH  bty, 2 X 9gm servos

AUW (all up weight)  comes to 670 gms / 23.6 oz  (this is coming out to be a bit too heavy for my liking... and could have been 75gms-100gms lighter if I had decided on the covering process and fuse construction right at the start.

Based on thumb rules the important parameters are
Metric Imperial
Wing Area 17.6 sq dm 1.8 sq ft
Weight 700.0 gms 24.7 oz
Wing loading 39.8 g/sq dm 13 oz/sq ft
Stall speed  14.8 mph
Wing cubic loading 9.8



The  hotwired wing, view of the tip profile




 The wing and the fuselage mated.. note the white plug, this will be used to form the fuse over
The underside.. This is still during the time when the covering was to be monokote.. ..hence the full length CF spar in the wing (the wider one is carbon unidirectional tow epoxied to the wing). Also the fuse has a aluminium U channel stuck on the underside..All these became redundant when it was decided to glass the wing and the fuselage underside

The top view which shows the carving/grooving for the motor wires, esc , rx, and battery








Below are some pic of the glassing of the wing











The  completed aircraft.. note the transparent cowling/cover of the front fuselage







... this is made out of a PET bottle heat formed (shrunk) around a plug, shown in white in the leading pic... This slips over the forward part of the fuselage and forms a housing as well as gives a streamlined shape and protects the underside.. the front portion of this cover is reinforced with a second cover made in the same manner and slipped one over other

She is great flyer . I get around 7 mins of flight time with a 3S 1500mah bty (mixed flying).. And she is fast.. as fast as radjet .. and with excellent flight characteristics .. my favorite aircraft for windy days

here is a pic of a inverted high speed low pass











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