
Designed by Paul Gentile This lightweight flying wing is an awesome fun flyer Free plans from Fall 2008 Park Pilot.
The idea for the RaeZA (pronounced ray-zuh) was born after I read about the U.S. Department of Defense’s DARPA program to develop Micro Air Vehicles (MAV). There are numerous MAV versions, all designed to be small and operable in the field. I figured that if the government could spend $35 million to develop MAV’s, I could spend at least a few bucks to develop an MAV of my own for RC. In true government form, I had to have a code name for the project. My eldest son settled the matter with RaeZA (Remote aircraft enjoyment-Zeta Alpha). Without access to government suppliers, the RaeZA does not carry GPS, cameras and autonomous computers. Instead, Du-Bro Products, E-flite, Midwest Products and Spektrum RC helped me outfit my model. The RaeZA uses an E-flite 180 brushless motor and 10-amp ESC, a 350mAh Thunder Power LiPo battery, Spektrum AR6100 DSM2 receiver and a pair of lightweight E-flite S-60 sub-micro servos. The RaeZA is a quick build and should only take an hour or two to construct. If you’ve never built from plans before, this is a great way to get started. There are only a handful of components, and this project is suitable for builders at any skill level. You’ll need a hobby knife and #11 hobby blades, a hot glue gun, E-flite Foam Safe CA and Activator, small pliers, a ruler and a fine-tip marker. Cut the parts from 3mm Cellfoam 88 from Midwest Products, which comes in packs of two. One 11.5 by 47-inch sheet is enough, so consider building a second RaeZA for a friend. You also need a roll of Du-Bro Electric Flyer Hinge Tape, one Du-Bro Micro Aileron System and Hook & Loop Material, a 22-inch length of Midwest 3mm carbon fiber tube and two straight pins. Make several copies of the full-size plan at the right on letter-size paper. If you have access to a copier that can make mirror copies, make one regular copy for the left side and a mirror copy for the right. Otherwise, make two regular copies, flip one over and trace the lines on the back of the page for the mirror. Tape the two pieces of paper together on the centerline, and that will be the center of the RaeZA.

The RaeZA can be built with basic hobby tools, Du-Bro Hinge Tape and E-flite Foam Safe CA.

Before taping the plan to the foam for cutting, cut out the servo placement area of the plan. This allows the transfer of markings from the plan to the foam instead of having to measure later on.

Once all the model’s components are cut from Midwest Products Cellfoam 88, transfer the servo placement, centerline, center of gravity and spar marks. Be sure to label each winglet and elevon left or right.

Lay out and adjust all your radio components before mounting to the wing.
Cut out the servo placement areas, leaving the outlines so you can use the openings in the paper to transfer the CG line to the foam. Use Du-Bro tape to hold the plan over the Cellfoam, making sure that both sides line up true and square. Check it with a straightedge across the center of gravity line. Cut out the wing as one large piece, and then cut the two elevons, two winglets and the motor mount. Cut the slots for the mount slightly narrower than 3mm for a snug fit. When all your components are cut, do not move them. Just remove the excess paper, leaving the parts and the plan where they are. Transfer the CG and spar lines to the foam. Extend the lines from the paper to the surrounding foam, then remove the paper and use the ruler to connect the dots. Trace the servo locations, and mark the two elevons and winglets for left and right. Remove the plan and the excess foam, turn the elevons over and cut a 45-degree bevel in the leading edges. Hinge the elevons to the wing with one piece of Du-Bro tape along the whole length of the hinge. Trim the elevon corners to prevent them from contacting the winglets in flight. If you fly outdoors and want a little more strength, run two pieces of tape from front to back on either side of the cutout for the motor mount, and one more piece along each of the wing’s leading edges. Start with half of the tape on top, then carefully fold it around to the bottom of the edge. Cut the carbon fiber spar to length and attach it with Foam Safe CA. Use the Du-Bro Micro Aileron System to activate the elevons, and secure the horns with Foam Safe CA. Use pieces of scrap foam to set the linkage. You will need to add roughly 6mm of reflex. Use hot glue to hold the servos and receiver; CA can wick into the equipment and do damage. Your transmitter will need to support a delta wing configuration or allow elevon mixing, the combined equivalent of elevator and aileron. This is what makes flying wings cool, like something out of a sci-fi movie. Attach the motor mount and the winglets with hot glue. The winglets attach along the dotted line and extend roughly 3mm below the wing. Create a glue fillet on the top and bottom where the winglets meet the wing, and be sure the winglets and the mount are square to the wing. Attach the aluminum E-flite motor mount with two pieces of Du-Bro hinge tape on each side and two straight pins. Tape the mount, then push the pins through the screw holes into the wing. Map pins with round ball heads work great. The ESC is held by taping the wires down, and a few thin strips of Du-Bro Hook & Loop can hold the battery. Cellfoam 88 is very versatile. You can go with the foamie look and leave it unfinished, or color it with markers or paint. I use an airbrush with water-based paint from the craft store for my camouflage theme. The top of the model is gray with random spots of khaki, and the bottom is light blue with a little white showing through.

Instead of trying to measure with a ruler, scrap pieces of foam ensure equal measurements of reflex and control horn height. Until setup is complete, use only light tape to hold servos in place.

Du-Bro Hinge Tape is very handy for holding down the ESC and the motor wires.

The author’s son, Paul Martin Gentile and his friend Matt Dobromilsky prepare to launch the RaeZA for the first time. Paul Martin wonders if this is going to actually fly.

At full throttle, the RaeZA moves along at a good clip, but well within Park Pilot guidelines.
Try a few test glides to get the balance and reflex set correctly. Toss the RaeZA into the wind with the nose level. The model should glide forward and level while losing altitude. If it pitches up or noses down, adjust the battery position or the reflex. If it turns to one side, you’ll have to adjust the elevons. When the balance and setup are right, it’s ready to fly. A word of caution here — the propeller may be small, but it can hurt you. Make sure that you can safely use an overhand or underhand launch before you try one with the motor running. The RaeZA flies just as well at the local gym as it does outdoors in light wind conditions. Choose an open area at least the size of a baseball diamond for flying outdoors. The RaeZA is loads of fun to fly, climbing to altitude, pointing the nose into the wind and cutting the engine back to just hang in the light breeze. It drops out after awhile, and recovers easily by adding a little throttle. She handles steady wind well, but she can change altitude very fast in gusty conditions. On my second day of trimming, I was making a low pass when a big gust of wind smacked her right down to the deck. There was no damage, but I was a very surprised pilot. My next outing was in zero wind, and everyone clamored for a turn on the sticks. We had a blast doing rolls and loops only a few feet off the ground. The E-flite 180 motor moves the RaeZA fast at full throttle, and most of the time we found ourselves flying at half throttle or less. The RaeZA’s small size makes it look like it’s moving along at a really brisk pace, but if you pull back and look at the bigger picture, it really isn’t fast at all. I guess it’s like doing 20 M.P.H. in a go-kart and 20 M.P.H. in a bus; the smaller size makes you feel like you are moving much faster. The RaeZA exceeds all my expectations, and my wife thinks it’s cute. The model has already made several road trips without any questions about why I am taking an airplane along. For me, that’s success. If you’re interested in flying wings or micro flight, the RaeZA is a great entry point for any intermediate pilot. It transports easily for lunch-hour fun, or those too-long road trips when you need something cool to fly.

Click here to download your free RaeZA Build It Plans.
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