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Showing posts with the label Foam aircraft

Hoi-Choi - Biplane

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 Always wanted to build a biplane.. and here is one.. It flies beautifully.. awesome slow speed characteristics, amazing roll rate... it parachutes down with power off Dimensions A simple rectangular wing, box fuselage made out of 5mm XPS sheet/depron makes it very easy to build, and it can be built very quickly. The research on CG of a biplane led to quite a range of literature, from simple to some very detailed ones (incl CLs of the airfoils)... finally KISS prevailed (keep it simple and straight).. The wing cord was taken as distance from the LE of the wing positioned ahead to the TE of the aft wing.. and it worked Another aspect which went through a similar approach was .."whether to have ailerons in top and bottom wing or only one (bottom) wing"... here again, went with having the ailerons ONLY on the bottom wing.. and it works. Electronics Motor - 2212, 1200kv (even 980kv will do, used this as that is what I could spare). Prop 9x4.7, Servos - 4 x 9 gms , battery - 1500 ...

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 w...

F-18 GROWLER

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This is a F-18 with 30" span and with a 2826 2000Kv motor It is based on a scale F18 Growler with some changes in the dimensions.. refer to the picture below for the dimensions It has ailerons, elevator and rudder as controls and one CF spar in the wing Has a wire skid fixed undercarriage, and can do a rolling takeoff from a decently flat surface.. A good  flyer, and with the heavier parts (motor, bty) close to the CG was quite maneuverable  .. The finished but unpainted version.. the picture gives a feel of the size The canopy can be removed to access the battery compartment It has flown many sorties.. and has been retired and parts recycles (like many of my planes.. storage is a challenge) Here is a flight video  https://www.youtube.com/watch?v=YPAsXsSOFqg&t=8s

Flying wing 54"-- with vortex generators

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This is a build log for a 54" flying wing with a blended fuselage  Made out of Styrofoam and hotwired Wing Span -  54" Airfoil - MH 64 Root chord - 14" Tip chord - 7" The wings were hotwired out of styrofoam based on a MH 64 airfoil. The spar was a strip of 1X3 carbon fiber glued in a shallow groove on the top and bottom surface of the wing. The two strips of CF act like a I beam with the foam in between, and being very strong in tension, makes a very rigid wing. There was a central section 6.5" wide fuselage, which was blended with the wings. This would help by having more space for power train & electronics  The CFs extended into the central section , which gave more rigidity and strength and intregrated the wings and fuselage better The LE was covered with very thin fiber glass to reinforce it against dents A view of the wings and fuselage joined together.. note the space being cut for electronics and battery.. . this would lat...