Rahul's RC Aircraft and other designs

DESIGN This design explores the region between a plank and a swept wing flying wing, and to try and get the best of both worlds to whatever extent possible.... The major balancing acts were being efficient across a large speed range, good C l /C d , less twist, and maintaining good flight characteristics. PLAN & DIMENSIONS A span of 1200mm was chosen to keep it a one-piece plane.  - Sweep is a very moderate 13 degrees measured at LE, and even lesser when measured at 1/4 AC line. - - Aspect ratio =- 6.3... (adequate wing loading with the set span of 1200mm span) - Taper ratio= 0.65 and Twist - (-)1 degree..... (close to elliptical lift distribution, less induced drag, while maintaining decent Re and flow characteristics at the tips, good stall characteristics) - Airfoil is PW51.. (good cl/cd, adequate +ve cm, and minimum trim losses).  - A central tailfin is chosen over wing tip fins.... (due the the less moment arm and the issues arising out of a badly designed wing tip ta...

 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...

 A slightly swept plank design.. a bow (something I was itching for a long time) .>The idea was to keep the planform as a plank (wider speed range) but with very moderate sweep to move the MAC a bit behind while avoiding some of the cons of a swept planform.  >Wanted to keep the TE straight, and the elevons not upto the edges to avoid unwanted separations.  >The thinning out of the airfoil thickness, rounding of the wing tips, and the very slight washout (1.5 deg) for a efficient span wise lift distribution and reducing induced drag. ( Peter Wick's Plank design was a big help). >The fuselage has been kept to a minimum with just a small pod in the front to house the electronics and boom at the back with the vertical fin Dimensions The wing is hotwired out of EPS.. Airfoil :  Root- phoenix 110% / P1 tip- phoenix 100% / Tip- phoenix 70%... There is a -1.5 degree washout between the P2 root and the tip The wing has a built-up CF tow cap spar at 35% ..it does ...

 This is a 1600mm high performance powered glider... composite construction Dimensions The wing is hotwired from EPS with airfoils as  AG34 : AG35 : AG36 The wings, tailplane and vertical plane are foam , fiberglass, carbon fibre composites which are vacuum bagged.  The wing is one piece with full length built up CF tow spar. and live fiberglass hinge for flaps and ailerons. It also has LE and TE CF tow reinforcements and also CF cloth reinforcement where the servos are mounted. The horizontal and vertical tail surfaces also have full length built up CF tow spar and well as LE and TE reinforcements. The fuselage is pod and boom. The pod is balsa, fiberglass composite with carbon fifer reinforcements at certain places. The boom is tapered CF tube.   The wing is mated to the fuselage with 2 x 10mm nylon bolts and nut. It can taken out for transportation and storage.  Electronics  2217 1000kv motor, 30A esc, 6 x 9gm micro servos, 2200 mah 3S bty AUW - 815...

 This is a 920mm span composite combat wing  The wings are hotwired out of EPS.. It has a built up a carbon tow top and bottom cap strip acting as the spar. The bottom hinged elevons have a live fiberglass hinge.  There is a LE carbon fiber cap strip and also a thin CF tow strip along the TE to prevent chipping. The whole thing is glassed with 30 gsm fiberglass .The winglets are fiberglass, carbon fibre & balsa composite The canopy is taped foam Dimensions      Root Cord = 30.5 cm      Tip Cord = 14.5 cm      Sweep = 30 degrees      Span = 92 cm     CG @10% SM = 15 cm from LE Electronics      2307 2550kv motor, 30A esc, 2 x 9gm micro servos, 1500mah 3S bty Dry weight = 325 gms, AUW = 480 gms With the CG at 7% , there is about 2mm up elevator required Excellent flyer... tracks like on rails..snappy in loops and rolls.. and good glide ratio too

This is a 1200mm plane built with a stick fuselage  The plan pic is below The wing has a Jedelsky airfoil, with the leading 30% cord made of 5mm balsa and the rest 70% cord made of 5mm depron. These two are spliced together and further stiffened with ribs. The ribs are also designed to induce a washout from root to tip.The planform design, specially near the tips also helps in reducing the camber near the tips.... All this is done to reduce tip stalling. It also has ailerons. There is a CF spar glued to the balsa. The Root rib is much thicker and reinforced. The dihedral is achieved but gluing together the root ribs .. they have quite some area in contact with the wing and between themselves.  Here is a pic of the same ..  The tailplane planform is also designed to handle high AoA without stalling. The tailplane is made of 10 x 5mm balsa frame and 5mm depron. This method adds a lot of stiffness without wt or requiring CF.  It has tape hinges.  The tail arm is lo...

 Here are the details of a SAL 1m plank wing glider The airfoil is PW1211. The wing is hotwired out of high density EPS. It has a 1mm CF rod epoxied to the underside , and a 5mm  wide CF tow lamination on the LE underside.. these act as spars. The TE has a 2 mm balsa 30mm wide, part of which is also the elevons, and balsa wing tips Fuselage is a 3 mm CF rod .. with some scrap balsa glued onto it to in front to act as the place to attach the RX and the battery.. the front part of the fuse is covered by a PET sleeve The wings are but joined with the 3mm CF rod sandwiched in between  and have two additional balsa joiners glued from top The whole wing and elevons are finished and coated with water based PU sealer mixed with light weight crack seal.  The rudder is glued onto the 3mm CF rod sticking out behind the TE It has two 4.5 gms servos controlling the elevons , and the 1s 350 mah bty directly plugs into the Rx. Dimensions Root Cord - 230mm (220 mm foam) Tip Cord - 1...

 This is a meter span flying wing designed for fast and aerobatic flying.. and it lives up to it The wing is hotwired out of high density EPS. The airfoil is PW51 at the root and PW51 at 120% thickness at the tip. There is no washout incorporated in the wing tip while cutting .. though there is a overall washout in the tip which we talk about latter The dimensions for foam cutting are It has one full length CF spar (4x1 mm) embedded on the top surface. The two halfs are but joined and the joint area has a 3 inch wide FG reinforcement. The motor mount is a ply and balsa embedded into the foam The elevons are 3 mm balsa. Cord 10mm near the root and 40mm at tip. This gives a natural washout at the tips The wing is covered with monokote .. (new technique) The pod top cover is made out  Electronics : 2 x 9 gm servos, 2207 2300kv motor (quad), 5x5x3 prop, 30A esc. I fly it on 3S Molicell Li-ion CG is at 190mm from LE apex She is FAAAAST .. very agile .. great flyer Flight video...

 Based on Loki.. and offsprings are bigger and better 😀 It is hotwired EPS foam vacuum bagged with fiberglass, CF .. It has a 16mm UD CF tape laid on top and bottom surface acting as a built-up spar. Dimensions   Airfoil :- TL16 110% thickness Initial CG (@7% SM) is at 20cm from LE apex Highlights 1. It has a 3x1mm CF strip slotted and epoxied into the LE...  prevent dinks 2. The bottom hinged elevons also have a top mylar gap seal ...  reduce drag  3. The servos, servo horn and push rods are embedded and completely enclosed within the wing. The  push rods run through tunnels with the wing, and come out just near the TE ..... reduce drag. 4. The battery and electronics are aligned longitudinally in the center of the fuselage top. It is just a 5cm strip.... keeping maximum surface of the wing clean for lift .. and reduces drag. 5. The vertical fins are 2mm balsa , carbon fiber, fiber glass composite . They are strong/rigid, light, and thin...... less d...