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Showing posts with the label RC aircraft

Flipper - Plank flying wing SAL

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 This is a Plank flying wing for SAL or bungee The dimensions are  Span = 875mm, Root cord = 260mm, Tip cord = 160mm, sweep = 60mm. 20mm constant cord full length elevons The wing is hotwired out of EPP and then laminated with thin iron-on laminating film. The airfoil is PW51 7% thick at the root and PW51 7.5% thick at the tip. It has a 1.5 degree washout and a 45mm dihedral at the tips.  It has one 2mmCF spar glued to the bottom positioned at 40% cord. There is also a spar on the top surface biased to the rear to avoid elevon reversal. Two 9g servos are positioned vertically into slots cut on the top of the wing. The position of the servos are driven by the thickness of the wing at that part and distance from CG. The full length elevon is a tapered 3mm balsa with fiberglass lamination. ....Note I had to increase the elevon cord at the tips by 12mmto improve the control response (after the first flight trials) The fuselage is a 3mm CF rod glued onto the bottom of the wing...

Vacuum bagging

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 This is a build log of  vacuum bagging Here the vertical fins of a swept  flying wing are being vacuum bagged.. The same technique can be used for any part.. (just that this is the one I documented) Of the different methods, this one uses a thin PET sheet as the finishing surface. This is different from using a peel ply. materials:- thin PET sheet, mold release wax, vacuum bag/ polyethylene sheet, vacuum bag sealing tape, some plastic pipe, vacuum pump/ brake bleeding pump. The foam blanks are readied.. making sure that surface finish is good and smooth and the surfaces are cleaned .. it needs to be understood that ANY surface imperfections more than the thickness of the FG cloth will be visible after glassing.. therefore though this step may seem trivial, it is quite important The pet sheet is cut in the shape of the part to be glassed, one for each side. At this stage it is not important for it to be absolutely accurate, I keep  around 1cm excess all around......

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 ...

Canary

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A swept flying e-powered wing.. this is loosely based on the "Sparian" with changes to the wing and fuselage .. and with e-power. The dimensions : Wing area = 26.85 dm sq, 416 in sq AUW = 650 gms  CG @10% SM = at 148 mm  of RC from LE Wing loading at 650 gms AUW = 7.93 oz/sq ft, WCL = 4.66,  stall speed =  22.2 kmph The wing is hotwired out of XPS (Blucore) and skinned with 80gsm fiberglass (one layer). It has a 10mm wide CF built-up cap spar on top and bottom, across the whole span. It is reinforced with a 30mm wide CF built-up spar to upto 230 mm from root, both top and bottom Fuselage is a simple box made out of coro with bamboo skewers inserted into  the flutes at certain areas for strength.  The wing is mated to the fuselage by two 8mm nylon bolts and then the edges are hotglued. This makes secured seating and at the same time can be disassembled, in case required.  Also vortex generators have been added. 5 sets of VG,s 70mm apart, extending, in t...

Joker

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A 1m  Thermal flying wing - Plank Dimensions and details :-             Electronics       a.        Motor = 2206 200KV b.        Prop = 7x4 folding c.        Bty = 2S  750/1000 mah d.        ESC = 30A 8.        AUW = 310g,  Wing area = 220000 sq mm, Wing Loading - 4.65 oz/sq ft, Wing cubic loading - 3 The wing is hotwired from EPS (Thermocole). It has a built-up 10mm CF tow spar  and skinned with 32 gsm fiberglass at 45 degree  bias. the wing tips are EPP . The fuselage is only in the front portion to house the ESC, RX, Motor and battery.. The vertical tail is stuck on a 3 mm CF rod and glued to the wing TE. The elevon is 3mm balsa sanded to a thin TE. The elevon is bottom hinged In the final version, the servos were moved inwards and positioned at the...

Condor - Thermal - powered glider

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  A thermal plank with low wing loading and a low drag airfoil. It has elevons and an active rudder. Dimensions and details Wing Span panel 1 =695 mm, Wing Span panel  2 =298 mm, Total = 1986mm The Airfoil - HS 117. Cord panel 1 =250mm, Cord panel 2 (tip) =150mm Sweep panel 1 =0, Sweep panel 2 (tip) =30mm Dihedral panel 1 = 20mm, Dihedral panel 2 = 150mm The Airfoil is HS 117. Vertical Tail to wing TE distance = 410mm, Vertical Tail cord 100mm, Vertical tail span 230mm Control surfaces are elevons and rudder The wing is hotwired out of EPS and covered with fiber-glass (vacuum bagged). The central portion has a CF tow (5mm) running on top and bottom. The two outer panels of 298mm each are detachable for ease of carrying.  The elevon cord is 40 mm and it is across the whole length of the inner panel. It has a kevlar hinge built into a skin, and the underside gap sealed with mylar (BO_PET) strip Wing area in inches = 723.4 sq inch Electronics 2212 9...

Javelin - high performance flying wing

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 Javelin is a high aspect ratio swept flying wing. It is designed for high performance  and uses modern airfoil and construction techniques.  The planform of the wing is as above with inboard flaps and outboard elevons. It has a fuselage pod and wing tip vertical fins,  Span : 1700 mm Root and Tip cord : 175 mm Sweep : 22.5 degrees or 353mm Flaps : length 240 mm, cord 30 mm, starting 25 mm from root at the TE Elevon : length 340 mm, cord 30 mm, starting 3 mm from tip Airfoil : HS 522 standard thickness and camber. It is low drag , low Re airfoil . The details and the .dat file can be found here  https://www.aerodesign.de/english/profile/profile_s.htm#hs522 Twist : 4 degrees AUW : 840 gms  Electronics : 2212 1400kv motor, 30A esc, 9X4.8 prop, 4 x 9gm MG servos, 3s 2200mah bty. (the electronics used are more from what I have, rather than the most suited) Wing Area : 297500 sq mm, 461.13 Wing loading : 9.36 oz/sq ft, and Wing cubic loading : 5.2 CG ...

JANUS - Aerobatic powered glider 40"

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A saw the video of the RedBull aerobatic glider team doing some exquisite flying and decided to  build something in those lines The design had to have low sink rate, Low drag, 4 axis control & low wing loading. Span : 1015mm Root Cord : 155 mm Tip Cord : 100 mm Wing LE to Motor : 175 mm Wing TE to Tailplane : 320 mm Tailplane Span : 305 mm Tailplane TC : 115 mm Tailplane TC : 85 mm Vertical surface ht : 130, Base width 115 mm The wing is folded out of 3 mm depron. It is 3 mm depron top and bottom surface with a depron spar.. The thickness is 9%.. so the spar is is two 3 mm depron overlapped to 3/4 span, the outer part of the spar is just a single strip of 3 mm depron (3+3+3=9 mm.. which is 9% of 100 mm) . The top and bottom sheets were laminated with 45 micron laminating plastic film, the fold was grooved from the inner side and the the top part slowly folded over and glued onto the spar and in the TE. The aileron is just the top surface extended The tail feathe...