Introduction. FlapJack. Kit Contents. Materials Required. Building Instructions.

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FlapJack Building Instructions http://www.backyardflight.com Introduction Thank you for purchasing the EFlight Designs FlapJack backyard flyer kit.

1 FlapJack Building Instructions Introduction Thank you for purchasing the EFlight Designs FlapJack backyard flyer kit. Please read these instructions in their entirety before beginning construction of your kit. If you have any questions while constructing the model, or call us and we ll be happy to help. Our contact information is: Phone: (9am 6pm Eastern Time) Web: Mail: PO Box 128, Lincroft NJ, Kit Contents The following items are provided in the kit: mm Carbon Fiber (CF) Rod Elevon Leading Edge Reinforcement mm CF Pushrods mm CF Rod Elevon Balance Rods mm CF Rod Wing Trailing Edge Reinforcement mm CF Rod Wing Leading Edge Reinforcement 1 1/8 Blue Foam Wing 2 1/8 Blue Foam Elevons 1 1/8 Blue Foam Vertical Stabilizer 1 Balsa Motor Mount Pylon 1 2 x ¾ Balsa Motor Mount Plate 1 1 ½ x ¾ Balsa Battery Mount Plate 1 1 ½ x ¾ Balsa Receiver Mount Plate 1 ¼ x 3 Lite Ply Throwing Grip 1 Lump of Balancing Clay 1 Length of hinge string 1 MPR-2 QuickConnect Pushrod Kit (control horns and linkage) Check your kit carefully upon arrival to make sure all the parts are included and none are damaged. If you find any damaged or missing parts, please contact us immediately to arrange for replacements. Materials Required Foam Safe Glue odorless foam safe CA and kicker is recommended. Otherwise epoxy or aliphatic resin (white glue). Sewing Needle Grit Sandpaper KP-00 Geared Motor (M-20 LV motor geared 2.75:1 with U-80 propeller) RFFS-100 Receiver (or equivalent) Two magnetic actuators Transmitter with elevon mixing Pins Wax Paper or other non-stick material FlapJack Building Instructions Page 1

Acknowledgements A big thanks to Roy Walton for providing the photographs used in these instructions, and for giving valuable feedback on the construction process and the original instructions.

2 Acknowledgements A big thanks to Roy Walton for providing the photographs used in these instructions, and for giving valuable feedback on the construction process and the original instructions. Wing Place the wing on a flat table covered with non-stick material like wax paper. Note the marks at the center of the leading and trailing edges of the wing. Connect the marks with a ruler or straightedge and lightly mark a 3 centerline flush with the trailing edge on the top of the wing. Flip the wing over and mark a 3 centerline flush with the leading edge. These will be guide lines for installing the fin and throwing grip later in the construction. Lightly weigh the wing down so it sits perfectly flat. Take the 9 length of 0.5mm CF rod and glue it to the trailing edge in such that it is centered on the face of the trailing edge. Be sparing with the glue, and allow it to dry thoroughly before proceeding. Do not bend or bow the CF rod, or else it will warp the wing. Use pins to hold the rod up against the foam. When dry, take a 6 length of 0.5mm CF rod and trim the ends to match the edges of the leading edge, then glue it to the leading edge of the wing in the same manner. Allow it to dry before proceeding. 6 CF Rod CF Rod Wing Top View 9 CF Rod Edge View Remove the wing and lightly sand the CF rod with grit sandpaper to remove any excess glue and make a smooth surface. Leave the trailing edge square, but lightly round the leading edge of the wing. Elevons Place each elevon on a flat surface covered with a non-stick material (e.g., wax paper). Weigh down the elevons so they are perfectly flat. Take a 4.25 length of 0.5mm CF rod and glue it on the leading edge of each elevon such that it is centered on the face of the leading edge. Make sure the rod is not bent up or down, or else the elevon will have a bow. Be sparing with the glue. Use pins to hold the rod in place as shown in the picture below. CF Rod Elevon FlapJack Building Instructions Page 2

CF Rod Elevon (Side View) Measure ½ from the inboard edge of each elevon and make a mark on the top of the elevon.

3 Allow glue to dry thoroughly. When dry, lightly sand the CF rod to remove any excess glue, and round the leading edge foam around the CF rod, such that the leading edge cross section looks like the diagram below. CF Rod Elevon (Side View) Measure ½ from the inboard edge of each elevon and make a mark on the top of the elevon. Glue a control horn at this location on each elevon, make sure the horn is perpendicular the leading edge, and that the hole in the control horn sits just in front of the CF rod. ½ Control Horn Finally, use a pin or small drill bit to drill a hole in the outboard edge of each elevon about ½ deep and at a 15 degree angle to the elevon edge. Glue a 1.25 piece of CF rod in each elevon as shown in the diagram. Don t try to just push the CF rod in, use a drill or a pin to make the hole first. CF Rod Drill Here FlapJack Building Instructions Page 3

Then measure ½ in from the inboard edge of each elevon and poke holes at this point on both the wing and the elevon. You should wind up with 8 holes total for 4 hinges.

4 Hinging Place the wing and each elevon on your worktable (with the control horns facing up) as shown in the diagram below. Measure ½ from each edge of the CF rod on the wing trailing edge and poke a small hole with a fine needle at this point just behind the CF rod on both the trailing edge of the wing and the. Then measure ½ in from the inboard edge of each elevon and poke holes at this point on both the wing and the elevon. You should wind up with 8 holes total for 4 hinges. Holes Next, you will hinge the elevons using sewn figure-8 hinges. Follow the steps below for each hinge: 1. Thread about 12 of the enclosed hinging string into your needle (or tack glue to a short piece of CF rod if you don t have a needle). Starting from the outboard side of the elevon, thread the needle from the top down through the hole in the elevon. Leave a couple of inches of string hanging loose on the elevon. Use a very small drop of glue to attach the loose end of the string to the top of the elevon about ¼ behind the hole, and allow to dry (foam-safe CA with kicker is best Wing Elevon for this). 2. Thread the needle up through the gap between the elevon and trailing edge of the wing and then down through the hole in the trailing edge of the wing. 3. Thread the needle up through the gap between the elevon and trailing edge of the wing (do not cross over the existing thread) then down through the hole in the elevon. Leave the remaining string dangling. Repeat this procedure for the inboard elevon hinge. We find that it goes quicker if you perform the first step (threading down through the elevon hole and gluing the loose string down) on all of the hinges and allow the glue to dry, then sew all four of the hinges in place at the same time. To secure the hinges permanently, pull the loose string on the bottom of the elevon to remove any slack. Make sure that the string is up tight against the CF rod. If not, give a slight tug to cut through the foam and pull out any slack that is created. Don t pull so hard that you bend or bow the foam, but pull it as tight as you can otherwise. Use your thumb to hold the loose FlapJack Building Instructions Page 4

string down on the bottom surface of the elevon, and apply a drop of glue about ¼ back from the hole and allow to dry. Then repeat for the three remaining hinges.

5 string down on the bottom surface of the elevon, and apply a drop of glue about ¼ back from the hole and allow to dry. Then repeat for the three remaining hinges. Cut off any extra dangling string, and you re done. Each elevon should flap freely with no binding whatsoever, and the gap between the elevons and trailing edge of the wing should be constant (about 1/32 ) across the whole elevon. If you don t get it right the first time, simply cut the string and try again, or carefully lift one of the glued-down string edges and pull it taut, then re-glue it. Elevon Balancing To get the maximum effectiveness from the actuators, the elevons should be mass balanced. Hold the wing level and let the elevons dangle freely. Add small bits of clay to the end of the balance rods until each elevon balances perfectly level, or with a small amount of up deflection. Each elevon should have same amount of deflection (none, or a slight up deflection). Add a small drop of glue to the end of the balance rods to secure the clay. Note that this will add a bit of extra weight, so you may have to remove a tiny bit of clay once the glue dries. Clay Weight Actuators Mount the actuators about 3 ½ up from trailing edge of wing (not the trailing edge of the elevons, but of the main wing). Line them up with the control horns so the pushrod run is straight. Mount small magnets near the actuators to provide a magnetic centering force such that the actuators will return to center by themselves when no power is applied. While the glue is drying, assemble the pushrods. First, tape down a piece of non-stick material (e.g., wax paper) on a flat surface. Then position a short brass Z-bend piece next to the end of the CF pushrod rod making sure they overlap by at least ½, and are lined up parallel to each other. Put a drop of CA glue on the pieces, check again that they are parallel and laying flat, and that the glue has spread across the entire bonding area, then spray with a bit of CA kicker. Repeat for the second pushrod. Once the glue has dried, temporarily install the actuator-end Z-bends in the actuator output arms, and the pushrods in the control horns. Measure and cut the pushrods such that they will overlap with the actuator end Z-bends by at least ¾ Next, remove the pushrods and Z-bend wires. Slip a piece of heat shrink tubing over the actuator end of the pushrods, then insert the Z-bend wires. Lay the assembled pushrods on a flat surface with the actuator-end Z-bends oriented they way they will be when installed on the model. Then use a heat gun to shrink the heat-shrink tubing until it is tight. Be careful with the heat-gun, the CF rod may soften and bend under high heat, so make sure there is no stress on the CF rod while shrinking. FlapJack Building Instructions Page 5

6 When cool, remove the actuator-end Z-bend from the heat shrink. You may have to twist it a little to loosen it up. Grasp the CF rod with flat-jawed pliers if necessary while twisting and pulling the Z-bend out. Finally, install the the pushrods in the control horns, and the Z-bends in the actuators, then carefully push the Z-bends back into the heat-shrink tubing. Set the length such that each elevon has about ¼ of up travel when the actuator is neutral. You will make final adjustments later in the construction after the receiver has been installed. When everything is assembled, you should be able to deflect the control surfaces manually, and have them return to center by themselves, with no binding. If there is binding, and a control surface gets stuck at deflection, the most likely cause is that the pushrods are not at right angles to the actuator output arms or control horns. Carefully use pliers or tweezers to make slight adjustments to the brass wires until the surface moves freely with no binding. Motor Glue the motor mount pylon to the front center of the motor mount plate. The pylon should extend in front of the plate as shown in the diagram. Pylon Top View Mount Plate Side View When dry, glue the motor mount plate to the leading edge of the wing, making sure the motor pylon is centered on the wing. Allow glue to dry before proceeding. Glue the motor to the top of the pylon, being very careful not to get glue on the motor shaft or inside the gearbox. Use a thick glue that will not run, and if using CA, spray it with kicker quickly before the glue has a chance to migrate into the gearbox. The motor should have 2-3 degrees of right thrust, and 8-10 degrees of upthrust. Note that we recommend the KP-00 motor and gearbox for this plane, and not the one shown in the picture. Final Assembly Glue the vertical stabilizer on the top of the wing along the center line you marked at the beginning of the construction. Make sure the stabilizer is 90 degrees square to the wing, and straight along the center line. Glue the throwing grip along the center line on the bottom of the fuselage. The front of the throwing grip should be flush with the front of the wing. You will get a stronger joint if you first cut a 1/32 slit along the center line and push the grip into the slit. Do not cut any deeper than 1/32, and be careful when pushing the grip into the slit so you don t split the wing. FlapJack Building Instructions Page 6

If it doesn t, move the battery forward or aft until the plane balances. Mark the locations, and permanently glue the balsa battery and receiver mounting plates in these locations.

7 Balancing Temporarily tape a battery and your receiver in place in one of the locations shown below using low-tack double-sided sticky tape. Hold the plane upside-down by the throwing grip and check the center of gravity (CG). The plane should balance at 2.5 from the leading edge of the wing. If it doesn t, move the battery forward or aft until the plane balances. Mark the locations, and permanently glue the balsa battery and receiver mounting plates in these locations. Motor Motor Receiver Battery OR Receiver Battery Actuators Actuators Fin Fin The CG range for this plane is 2.25 to 2.75 back from leading edge of wing. We suggest first flights are with the CG in the middle or forward part of the range until you get the feel for the plane. The CG can then be moved back by shifting the battery to get more sprightly aerboatic performance. Radio Setup And First Flights Connect the motor and actuators to your receiver. Attach the antenna to the receiver and route it to the top of the vertical stabilizer, securing with a bit of tape. Turn on your transmitter, and make sure elevon mixing is enabled, and that the throttle is all the way down. If using an RFFS-100 receiver, and if your transmitter has Adjustable Travel Volume (ATV) or Endpoint Adjustment (EPA), set it to 120% for both the aileron and elevator channels. Connect the battery to the receiver and test the actuators. The elevons should both go up when you pull back on the elevator stick, and both go down when you push forward. If they don t, either reverse the actuator connection at the receiver, or reverse the channel in the transmitter for the offending elevon. When you stick left, the left elevon should go up and the right elevon should go down, and vise-versa when you stick right. At full deflection, the actuators should stop chirping, indicating that full power is being delivered to the actuators. If the chirping does not stop, increase your ATV or EPA adjustments to the maximum. Make any final adjustments to the pushrod lengths such that the elevons have approximately ¼ to 3/8 of reflex (up travel) measured from the bottom of the elevon when the stick is at neutral. Also, make sure both elevons have the same amount of reflex at neutral. When you are happy with the pushrod lengths, use a very small drop of medium FlapJack Building Instructions Page 7

8 or thick CA glue on either side of the heat-shrink tubing to secure everything. Spray some kicker on the CA to prevent it from wicking too far into the heat-shrink tubing (use foam safe CA and kicker if working with a foam model). Adjustments can be made later by softening the CA with some debonder or acetone (again careful around foam!) and using pliers to make small adjustments to the pushrod length. We like to flight test first before applying the glue. At the forces involved with small models, the friction alone is normally enough to hold everything in place. If you have dual-rate switches on your transmitter, we recommend selecting 60% low rate and 75% high rate on both aileron and elevator, and that you start your first flights on low rates until you get the feel for the airplane. As you get accustomed to the aircraft, increase the high rates until you are satisfied with the aerobatics. We also recommend a healthy amount of negative exponential to reduce the sensitivity of the stick around neutral, as it makes it easier to do gradual maneuvers when on high rates. Don t forget to test the motor and make sure the prop blast is felt behind the propeller and not in front of it! Reverse the connections if needed. Launching To hand launch, hold the plane by the throwing grip near the CG using your left hand (if righthanded), raise the throttle to 100%, and with your other hand on the aileron/elevator stick give the plane a gentle toss into the wind. Don t throw it hard, just give a gentle push forward. Be ready to give some up elevator if it starts to go down (correct this with up elevator trim, or by moving the CG rearward). An alternate launch method is to hold it by the side with your palm underneath the plane and launch it sidearm-style. Don t try to throw it like a Frisbee just a gentle push forward to get it started. With a KP-00 at full throttle, the plane will climb easily and gain speed quickly from a dead stop. Landing To land, reduce power, and begin to feed in up elevator to raise the nose and increase the angleof-attack of the wing. The wing will fly slowly at high angles of attack and remain stable as long as there is some power applied. When you are a few inches from the ground, cut all power and pull back the elevator for a dead-stop full-stall landing. Flight Characteristics If you find the plane tends to go down, increase the reflex in the elevons by adjusting the pushrods, or adding up-trim. Alternately, move the CG back a little bit by shifting the battery aft. As the CG is shifted rearward, the loop and roll rates will increase dramatically. Be ready for it! Enter inverted flight from a half-inside loop. You will need significant down-elevator to maintain inverted flight. Best not to try it too low to the ground until you are accustomed to the feel of the airplane. The nose tends to drop in a roll, leading to a split-s instead of completing the roll, especially with a forward CG. Practice at a safe altitude, and be ready to apply downelevator when the plane is inverted. Copyright 2003, EFlight Designs, LLC. All Rights Reserved. FlapJack Building Instructions Page 8

I n s t r u c t i o n M a n u a l. Instruction Manual SPECIFICATION

I n s t r u c t i o n M a n u a l Instruction Manual SPECIFICATION - Wingspan: 3200mm (125,9 in) - Length: 1650mm (64,9 in) - Flying weight: 3000gr 3200gr - Wing area: 64.5 dm2 - Wing loading: 46g/dm2