assembly and flight manual - ep.yimg.comep.yimg.com/ty/cdn/unicornwings/manual.pdf · a new product...

Copyright © 2002-2004 Unicorn Ventures Ltd. Patent pending

~ The finest radio-controlled electric powered flying wing in its class ~

Assembly and Flight Manual

Unicorn Ventures LLC P.O. Box 65167 Shoreline, WA 98155

Email: [email protected] Phone: (206) 440-5843

WWW.UNICORNWINGS.NET

The Unicorn Assembly and Flight Manual

of 48 Copyright © 2002-2004 Unicorn Ventures Ltd. Patent Pending. All rights reserved

INTRODUCTION ..................................................................................................................................................................3 SPECIFICATIONS ....................................................................................................................................................................3 HOW DOES IT WORK?.............................................................................................................................................................4 FEATURES AND BENEFITS......................................................................................................................................................5 KIT CONTENTS.......................................................................................................................................................................6 ADDITIONAL MATERIAL NEEDED...........................................................................................................................................7 SUGGESTED TOOLS................................................................................................................................................................8

ASSEMBLY CONSIDERATIONS .......................................................................................................................................8 PRECAUTIONARY NOTES........................................................................................................................................................8 CUSTOM MODIFICATIONS ......................................................................................................................................................8

ASSEMBLY PROCEDURE ..................................................................................................................................................9 PREPARE THE WINGS .............................................................................................................................................................9 INSTALL THE MOTOR TUBE ..................................................................................................................................................10 GLUE THE CARBON SPARS ...................................................................................................................................................11 ELECTRONICS SETUP AND TEST ...........................................................................................................................................12 BATTERY BAY MODIFICATIONS ...........................................................................................................................................14 RECEIVER CUTOUT AND ANTENNA SLOT..............................................................................................................................14 ROUTE THE ANTENNA WIRE.................................................................................................................................................14 SERVO CUTOUTS..................................................................................................................................................................15 INSTALL SERVOS .................................................................................................................................................................16 SECURE THE MOTOR IN THE TUBE........................................................................................................................................16 COVERING PREPARATION ....................................................................................................................................................16 FILAMENT TAPING AND COVERING ......................................................................................................................................17 PROCEDURE; FILAMENT TAPING ..........................................................................................................................................17 PROCEDURE; COVERING......................................................................................................................................................20 SAND AND TRIM THE ELEVONS ............................................................................................................................................22 CUT, TRIM AND SAND THE WINGLETS ..................................................................................................................................23 TAPING THE ELEVONS AND WINGLETS.................................................................................................................................23 ATTACH THE ELEVONS ........................................................................................................................................................24 TAPE RACING STRIPES AND LEADING EDGE..........................................................................................................................25 ELEVON CONTROL ROD INSTALLATION................................................................................................................................25 INSTALL THE PROPELLER ONTO THE MOTOR ........................................................................................................................27 ATTACH THE WINGLETS ......................................................................................................................................................27 FLIGHT CONTROL SYSTEM ADJUSTMENT .............................................................................................................................28 BALANCING THE AIRCRAFT .................................................................................................................................................29 WINGSPAN MODIFICATIONS.................................................................................................................................................29

GENERAL FLYING PRECAUTIONS ..............................................................................................................................30 BATTERY PACK TIPS.......................................................................................................................................................30 FLIGHT CHECKLIST ........................................................................................................................................................31 LAUNCHING........................................................................................................................................................................32 TROUBLESHOOTING .......................................................................................................................................................33 WARRANTY ........................................................................................................................................................................34 CREDITS...............................................................................................................................................................................34 CUSTOMER PHOTOS........................................................................................................................................................35 CUSTOMER COMMENTS ................................................................................................................................................36 Created 10 June 2002 Version 6.1 3 July 2004


Copyright © 2002-2004 Unicorn Ventures Ltd. Patent Pending. All rights reserved. of 48

Introduction The Unicorn is a radio controlled flying wing that has been designed to offer convenient flying fun for flying model hobbyists, at a reasonable price.

The Unicorn is great for beginners, because it has favorable low speed gliding characteristics, and the wings are made of resilient foam (EPP) that bounces upon impact. Experienced pilots will appreciate this fully aerobatic aircraft that is capable of high speed rolls, loops and inverted loops. The Unicorn offers flight times that are typically longer than the competition owing to its carefully designed propulsion system and airfoil.

The Unicorn is electric powered, using a rechargeable battery pack that can be quickly swapped and recharged in the field. Very little flight preparation time is needed, unlike gas (glow) powered aircraft.

Specifications When constructed as described in the instructions, the wingspan of the Unicorn is 48 inches, which is best for beginners. However, you can shorten the wingspan afterwards in order to increase the Unicorn’s aerobatic maneuverability and top speed.

48 inch wingspan 42 inch wingspan 36 inch wingspan Distinguishing features

Best for beginners. Multi purpose flight including fun flying and slope soaring.

For pilots with intermediate experience. Offers aerobatic control and good low speed stable behavior.

For expert pilots. Highest performance aerobatic flight. Higher top speed, and considerably faster rolls and loops.

Battery pack(s) used

8-cell 1300mAH NiMH (8 ounces) Smaller cells down to 5 ounces are possible, such as a 7-cell 600mAH NiCad

8-cell 1300mAH NiMH 8-cell 1300mAH NiMH

Wing Area (ft2) 3.75 3.42 3.05

*Estimated Weight including Battery (oz)

23.8 (1300mAH pack)

23.1 22.4

Wing loading (oz/ft2)

6.35 6.75 7.34

Balance point, as measured from the nose (inches)

10” 9.75” 9.5” to 9.75”

* Using the GWS Pico 4-channel receiver (6 grams) and (2) Hitec HS81MG servos (2 x 19 grams)



How does it work? Flight control of a flying wing is generally made possible through the use of control surfaces on the trailing edge of each wing. These control surfaces are commonly known as “elevons”, a term derived from a combination of the conventional names of airplane control surfaces, “elevator” and “aileron”.

You configure your radio system so that the first two channels of your transmitter (aileron and elevator) are programmed internally; the two channels are mixed and transmitted to the receiver in “elevon” mode. When programmed in this manner, pulling back on the stick (up elevator) results in both elevons deflecting up an equal amount, which is the means of making the plane go up. If you push the stick to the left (left aileron), this results in the left elevon going up and the right elevon going down. This provides the equivalent of aileron control (roll) to the flying wing, and is the means of turning the plane to the left.

The Speed 400 electric motor thrust can be proportionally set anywhere from 0% to 100% by the microprocessor-based speed controller. The speed controller is controlled by the throttle channel of the radio system, this is usually channel 3. The speed controller works by turning the motor on and off approximately 1000 times per second. The speed controller sets the motor thrust amount by adjusting the ratio between the power on time and the power off time.

The speed controller contains a built-in Battery Eliminator Circuit (BEC) eliminating the need to have a separate battery pack to power the receiver, and an electronic brake that prevents or reduces propeller “windmilling” when the motor is unpowered. Further, when the battery pack voltage falls below a pre-set level, the speed controller automatically shuts off the power to the motor, in order to ensure that enough battery power remains to glide the plane in for a safe landing.

It is important to land the plane shortly after this happens, to avoid eventually losing control of the plane.



Features and Benefits

Exceptional flight performance

Flight duration and powered climbing is superior to many other commercially available flying wings, owing to lighter wing loading, an aerodynamically improved wing, fully embedded battery pack and motor, improved propulsion system, larger wing area, and careful selection of a NiMH battery pack that offers superior energy density. Total flight duration is typically 15 to 30 minutes or more, depending on how aggressively you choose to fly and whether you fly in an area where thermal or slope lift is available. The Unicorn flying wing will maintain a constant altitude at approximately 25% throttle, unlike other electric powered flying wing designs that may require 50% or more throttle to maintain altitude.

Electric power There are many benefits of electric power:

Flight preparation time and cleanup are minimal; no internal combustion engines (glow powered engines) to deal with.

No need to keep stocking up on fuel.

Electric is less expensive and generally safer than glow power.

Electric power is non-polluting.

You can rotate several rechargeable battery packs in the field, for extended flying time.

Crash resistance All EPP (expanded polypropylene) wing material combined with the overall light weight, allows the plane to “bounce” upon hard landing; this is an important feature for beginners.

There is no central plastic fuselage that can shatter upon hard nose landing.

The Unicorn is a pusher-power design; the propeller and motor are located behind the wing. This reduces the possibility of damaging the propeller or motor.

All electronics and the battery pack are protected against impact, as they are securely installed completely inside the wing.



Kit contents The full kit contains everything you see on this page. However, you can order the Unicorn core kit or the Unicorn propulsion kit as separate items.

Unicorn core kit Qty Item

1 EPP Foam wing core set 1 Carbon fiber spar, 29.5” long 2 Carbon fiber spars, 14.75” long 1 Holographic plastic covering film 2 Control horns 2 Threaded 2-56 push rods with nylon

clevises 2 Solderable clevises 1 High impact PVC Plastic crash

resistant motor tube system including aluminum backing plate and hardware

1 1/16” thick balsa sheet, 4” x 24”, for winglets

2 1/8” thick balsa elevons 1 Clear plastic battery bay cover flap 1 Pair mating Velcro strips for

securing battery and battery bay; 6” long

1 Roll 1½ ” wide filament strapping tape

1 Paper template set 1 Assembly and Flight Manual 1 Small EPP block 1 Decal sheet

Core kit components

Unicorn propulsion kit Qty Item

1 Speed 400 6V motor 1 Gunther plastic propeller 1 20A Electronic Speed Control

(ESC) with built-in Battery Eliminator Circuit (BEC) and electronic brake

1 8 cell 1300 mAH NiMH KAN battery pack

1 Male Deans Ultra plug with red and black leads (for charging the battery)

Propulsion kit components



Additional material needed The following items are not included in the standard Unicorn offerings and must be purchased separately. Use this list as a shopping checklist.

Check off

Qty Item

The following items can be found at hobby shops or on the Internet: 1 Radio Transmitter with at least 3 channels; elevon mixing feature

recommended (without elevon mixing, you will need to purchase an elevon mixer that you must install in the plane). Transmitter “Exponential servo control” capability is desirable, but not required, for higher performance flight handling. A new product from Hitec (www.hitecrcd.com), the Neon, offers promise as an inexpensive yet reliable transmitter.

1 Light weight receiver, dual conversion style recommended. Some recommended dual conversion receivers are:

FMA Direct Extreme 5 Sub Micro Receiver ( http://www.fmadirect.com )

Hitec 555 ( http://www.hitecrcd.com ) 2 Hitec HS81 Micro servos are recommended (approximately .65 ounces) or

Hitec HS81MG (metal gears instead of plastic gears for impact damage resistance)

1 Battery pack peak charger. You should choose one that can accommodate NiMH and NiCad battery packs, capacities from 600mAH to 1650mAH or more, and can recharge at least 8 cells. Some recommended chargers:

Maha MH-C777PLUS-II (also charges many types of lithium cells) at http://www.nimhbattery.com.

Dymond Super Turbo Charger at http://www.rc-dymond.com. Assorted Covering material. For lightest weight and lowest cost use 2” wide 2.2 mil poly

tape, available at www.unicornwings.net, hobby shops or packaging supply stores. Alternatively you can use model aircraft covering film such as Ultracote, EconoKote, or Oracover. Use these low temperature shrink films instead of conventional heat shrinkable coverings such as MonoKote, to prevent heat damage to the EPP foam wing when shrinking the film.

1-2 (Optional) 6-12 inch servo extension cord, connector style depends on manufacturer of servo and receiver (allows controlling elevons nearer the elevon midpoints; offering better high speed control)

The following items can be found at home improvement stores or possibly at hobby shops:

1 kit Polyurethane glue, such as Elmer’s ProBond (for gluing the carbon spar inside the wing)

1 can 3M Super #77 Spray Adhesive 1 tube RTV Silicon glue (electronics grade preferred) 1 roll Blue masking tape 1 roll 3M carpet tape (Double-backed) Assorted 150 to 220 grit sandpaper 1 jar (Optional) White drywall spackle for filling foam slots, blemishes or holes



Suggested tools Check off

Tool

X-Acto knife kit with new, sharp blades Sharpie permanent fine tipped marking pen Pencil Straight edge (ruler or straight yardstick) at least 24” long 90 degree square Sharp scissors Sanding block (construct your own from a stick 1” wide x 8” long, attaching #220

sandpaper to it using double-backed carpet tape) Soldering iron and rosin core solder Cutting board Small screwdriver set (Optional) Dremel motor tool kit Portable vacuum cleaner

Assembly considerations

Precautionary notes The overspray produced by Super 77 spray adhesive is very sticky. For this reason we recommend using the spray outdoors, and that you point the spray tip downwind, so that the overspray blows away from you, and away from objects that you do not want to make sticky (!). Also use masking tape and newspaper to mask those parts of the wing that you do not want sticky.

Do not connect the battery pack to the speed controller until all of the electronics assembly steps have been completed and the transmitter is turned on. Otherwise you risk damaging the speed controller, particularly if the motor wires happen to be shorted together when you do this.

Custom modifications The single most important factor that affects flight performance is weight, followed closely by strength.

Weight considerations Any modification that adds weight behind the balance point (center of gravity point) will make it difficult to move the CG forward again without adding more weight.

Custom modifications, reinforcements or substitutions may require additional balancing weights. If assembled in accordance with the instructions, all balancing can be accomplished through repositioning of the battery pack.

Avoid using glues such as Epoxy which are brittle and can add considerable weight. In general, your glue joint does not need to be any stronger than the EPP foam wings. Do not use “Goop” in the spar slots to avoid risk of melting EPP foam.

We recommend you continue to use stiff 1/8” balsa for the elevons; thinner or lighter balsa may warp excessively during high speed flight.

The taping method described in this manual results in a covering that is lighter than other low temperature covering materials such as Ultracote. If you choose to use an alternate covering material that you wish to shrink with heat, it must be able to shrink at a low temperature to avoid melting the wing core foam. You also



must be very careful to avoid warping the wing during the shrinking process.

You can be very creative with your airplane color patterns using colored tape.

Propeller modifications You can change to a propeller other than the Gunther but you will require a prop adapter. If you change to a propeller that loads the motor down more than the supplied propeller, be careful to avoid exceeding the maximum current rating of the speed controller (the speed controller is rated at 20 amps peak). You will need a wattmeter and/or ammeter to check this.

Alternative propulsion systems The Unicorn accommodates many different motor, propeller and battery pack systems, including high performance brushless motors.

The battery pack will need to be in a “flat” pack form; the pack must fit inside the wing, so there is a practical battery pack thickness limit of approximately 0.8 inches. The Unicorn battery bay has been precut to accommodate battery packs that consist of AA or 2/3 A sized cells. You can cut the battery bay deeper or wider as needed.

You can use the Unicorn 1300maH 8 cell KAN NiMH battery pack with a high performance brushless motor, if you choose a propeller that results in a current draw of no more than 20 amps maximum. If you want to build a maximum thrust, “Unicorn rocket”, consider using a brushless style motor, with alternative batteries that can deliver even higher amperage, or higher voltage (more cells). The Unicorn 1050mAH 10 cell KAN pack is an example. Some brushless motors can require up to 25 amps or more, depending on the choice of propeller.

You can use an available motor analysis program to help choose a propulsion system: see the following web site: http://www.motocalc.com. When running this program, choose an airfoil that looks close to that of the Unicorn. The Unicorn uses a flat-bottomed foil shape.

Depending on the choice of motor and current draw, you may need additional cooling of the battery pack, speed controller or motor. You can increase the air flow into the battery bay by cutting the battery flap to be slightly narrower in width. This results in a wider air intake slot following the two long sides of the battery bay.

More user implementations and ideas can be found in the RCGROUPs on-line forum, at http://www.rcgroups.com, in the Airplanes – Electric section under the subsection named Foamies (or Search for Unicorn).

Assembly procedure

Prepare the wings Remove the wings from their surrounding EPP foam beds. The EPP foam beds can be used to hold the wings steady and flat during construction, but you must separate the top foam bed from the bottom bed. Bend a foam bed apart, and use a knife to cut the top bed away from the bottom bed, along the leading wing edge line. You will end up with a “top” wing bed and a “bottom” wing bed. Do this to both wing sections.

Rub the supplied small EPP foam block against all wing surfaces, in order to remove the plastic “stringers” from the surface. Also remove the stringers from the EPP foam wing beds. Vacuum while working. On the front wing edges, carefully pull away any remaining stringers.

If desired, sand the wing surface with a sanding block, in order to improve the final wing finish. This is particularly recommended if you intend to later apply drywall spackle to the surface in order to create a flawless finish.

Trim the edges of the wing motor cavity as needed, for a smooth and symmetrical top-view appearance:



The next photo shows the trimmed cavity edges:

Install the motor tube Your kit is supplied with one of these motor tube packages: Part no. Used for this style motor

UVMT2 Speed 400 or Mega 16/15/… series brushless (1.1” diameter, up to 1.75” long)

UVMT3 Astro 020 series brushless (1.0” diameter, up to 1.75” long)

The redesigned, tougher Unicorn motor tubes use high impact 1/16” thick walled PVC tubing. Each includes an internal motor stop, an aluminum backing plate and the necessary attachment hardware.

(Tube style UVMT2 is shown above)

The inner motor stop is locked in place with one of the supplied screws. If desired, you can glue this inner tube for added strength. PVC cement, commonly available at home improvement stores, is ideal for this.

The motor stop can be adjusted to accommodate different motor lengths by re-drilling the hole in the internal motor stop.

You can use 3M77 adhesive spray throughout, for gluing the motor tube kit to the wing cores. Or you can use epoxy cement. Epoxy may be somewhat stronger, although it adds a little more weight.

De-burr and clean the motor tube and the aluminum backing plate. Rough up one side of the backing plate with sandpaper so glue will adhere to it better. Then clean the sanded side of the plate.

Apply your choice of covering to the motor tube. You can mist the motor tube with 3m77 spray before covering, in order to better adhere the covering to the tube.

In the images that follow, covering material has not been applied to the tube, for better construction visibility.



Dry fit the motor tube into the wing body and carbon spar as shown. Note how the carbon spar fits into the motor tube spar notch. Notch the foam edge using scissors, at the bolt holes, to make it easier to install the bolts later.

Spray some 3M 77 adhesive spray into a small disposable cup. Let some of the solvent evaporate, this takes a few minutes. Using a small brush, apply 3M 77 adhesive spray to the root ends of both wings (where the two wing halves mate), and wherever the wing foam will contact the motor tube (unless you choose to not glue in the motor tube).

Carefully install the motor tube. Avoid shifting the tube, to prevent spreading glue onto the visible part of your motor tube.

Install the other wing half, taking care to align the two wing halves while sticking them together.

Spray a thick coating of 3M77 adhesive spray onto the sanded and cleaned surface of the aluminum plate. Paint some 3M77 adhesive spray onto the foam, where the aluminum plate will be applied. Alternatively, use 5-minute epoxy. Install the plate using two supplied #6-32 machine screws, four washers and two nuts. Do not over tighten the screws, in order to avoid warping the aluminum plate. To keep the nuts from vibrating loose you can apply some silicon rubber cement to the exposed screw threads inside the tube.

Bottom view, showing aluminum plate, screw heads on the outside, and a washer under each screw.

Top view, after assembly; note washer under each nut, inside the tube.

Apply 12 inch lengths of filament tape across the top and bottom surfaces of the joined wings, stretching the tape somewhat while applying to ensure the two wing root faces remain seated together until the cement adhesive bonds. Remove this tape after the glue dries.

Glue the carbon spars Invert the wings in order to have access to the spar slots on the bottom, and place them on their matching top foam beds, laid flat on a table.

Slide the two 14 ¾” long carbon spars into the slot holes in the wing tips. The photo below shows spar orientation; note that the spars overlap somewhat:

Run a strip of blue masking tape on each side of all three spar slots, leaving each spar slot open to accept glue.



Inject spots of polyurethane glue into each spar slot at 1 – 2 inch intervals. Push the glue nozzle all the way down to the spar, ensuring that the glue will work its way down and around the embedded spar.

Since the wing is EPP, you can bend the wing somewhat in order to open up the spar slot while gluing. Wipe excess glue from the masking tape on the wing surface. Keep the blue masking tape in place while the glue sets, because polyurethane glue foams up (filling in the gaps between your glue spots) as it hardens.

Electronics setup and test Charge your airplane battery pack and your transmitter.

Ensure that your transmitter and receiver are set up with the correct crystals and the same frequencies. Do not power up your transmitter if you are near an AMA-sanctioned field, without registering with them first, to avoid inadvertently crashing someone else who may be using the same frequency.

Do not connect the battery pack to the speed controller until all of the following assembly steps have been completed and you have turned on the transmitter. Otherwise you risk damaging the speed controller, particularly if the motor wires happen to be shorted together when you connect the battery pack.

Solder the blue and red motor wires from the speed controller, directly to the motor tabs.

Since the motor is to be used in a pusher configuration, these wires typically need to be reversed. Note that some Speed 400 motors are labeled with the polarity already reversed, for pusher configuration, so this does not apply. Therefore, solder the blue wire to the motor tab that is identified with a red dot or a + symbol marked nearby. Solder the red wire to the remaining motor tab. The motor is supplied with two noise suppression capacitors; they are located either on the inside of the motor or on the outside of the case. Each capacitor connects between a motor terminal and the motor case. Note that it may be necessary to solder a third capacitor (supplied with the speed controller) across the two motor tabs, if your receiver system is experiencing radio-frequency (RF) noise.1

The speed controller may be supplied with an “arming switch”, attached to the speed controller with a pair of wires.2 1 The speed controller / motor combination produce the most RF noise when the throttle is partially on. This is because when an intermediate throttle position is chosen, the speed controller is rapidly turning the motor full on and full off (approximately 1000 times per second) while dynamically adjusting the ratio of the on vs. off time to establish the throttle level. 2 If this switch is bumped into the off position during flight, or is not switched fully into the ON position, the electrical system can fail during flight. For the purpose of keeping the speed controller under the controller manufacturer’s warranty, you should initially leave the switch as is; consider removing this switch completely, twisting together and soldering the two wires together, and then insulate the solder joint with 1/16” heat shrink tubing or electrical tape.



Connect the speed controller’s 3-terminal universal receiver servo connector to channel 3 socket (throttle) of the receiver system (not the battery slot), while carefully observing the polarity of the connector before inserting. The black wire must correspond to the negative (-) or ground pin on the receiver.

The speed controller contains a built in Battery Eliminator Circuit (BEC). The receiver and the elevon servos will obtain all power from the 3-wire speed controller cable. For this reason, do not plug a secondary receiver battery into the receiver. All power is supplied by the main battery pack, through a voltage regulator built into the speed controller.

The above instructions are slightly modified when using older Airtronics systems.3

Loosely install the long horn style plastic servo arm (supplied with the servo) into each servo.

Position the servos on the table, in the same orientation that they would be used in the plane:

Secure the motor (with NO propeller attached) onto your work bench. Filament tape works. It must be secured, to prevent the motor from spinning and twisting the motor wires.

Connect elevon servos to your receiver channel sockets 1 and 2. 3 The speed controller’s servo connector works with all receivers except the older Airtronics style. The newer style is identified by the incorporation of a blue colored wire for the servo signal wire. For use with the older style Airtronics receivers, swap the red and black pins in the plastic housing of the speed controller connector, and when plugging into the receiver, red goes to the outside of the receiver.

Set the throttle stick (usually found on the left side of your transmitter) to the full off (down) position. Set the throttle trim control to the middle position.

Turn your transmitter on. Note that the transmitter is always the first thing you turn on, and the last thing you turn off. Verify the transmitter has a full battery charge.

If your transmitter is programmable, make sure your transmitter’s throttle channel is NOT set in the REVERSE direction.

If you have an arming switch on the speed controller, switch it to the ON position.

Program your transmitter for Elevon (or Delta) mixing on channels 1 and 2. Refer to your radio’s instruction manual for details.

Set all trims on your transmitter to zero position.

Plug the battery pack into the speed controller. The motor should not turn on when you do this.

The LED on the speed controller should start to glow. This LED glows if the throttle is completely off (and armed) or completely on, but not in between.

If the LED does not start to glow after a second or two, this typically indicates that the transmitter throttle stick is not set in the off position, and the speed controller will remain nonfunctional (unarmed) until the stick is moved in the off position. This is a safety feature.

If the controller will not arm when the stick is in the off position, the controls are likely reversed; verify this by moving the stick to the opposite extreme. You may need to adjust the throttle trim control as well. If the LED turns on with the throttle fully on (yet the motor is not running), your stick is reversed, and you should be able to turn on the motor by slowly lowering the stick. A reversed throttle stick can be corrected by programming your transmitter to reverse the throttle channel.

Remove the plastic servo arms from the elevon servos, and reinstall them so that they are as close to vertical as possible.



If installing servos and control linkages on top of the wing (recommended), both servos should move forward when the transmitter stick is pulled towards you (as aircraft is viewed from the rear). If this does not happen, unplug power and reverse the servo cables for channels 1 and 2.

The servo arm on the right should move forward (and the servo arm on the left should move backward) when you move the transmitter stick right.

You may need to reverse the servos (swapping channels 1 and 2), and/or program the transmitter to reverse one or both servos.

Unplug the battery pack from the speed controller, and then turn off the transmitter.

Battery bay modifications The battery bay is cut out to accommodate battery packs that are laid out in a flat configuration, using AA or 2/3A style cells. For example, you can use 8 x AA-sized cells positioned side by side (IIIIIIII), or any configuration that is of similar dimensions. If you are using a different battery pack style, modify the battery bay dimensions as necessary. The pack and battery bay should be shaped so the battery pack can be shifted in the bay, towards the nose or tail of the wing, to allow for aircraft balance fine tuning. The battery pack should weigh in the range 5 to 10 ounces in order to achieve aircraft balance without having to add ballast weight.

Receiver cutout and antenna slot On the bottom wing side, use the supplied receiver positioning Template #3 to locate where the foam needs to be cut out for the receiver. Mark the center point of the receiver, and use the profile for your actual receiver when you cut your receiver opening; center your receiver profile in the area shown on the template. This ensures that the receiver is placed in between the battery straps that are installed in a later step. Locate the receiver on one side of the battery compartment, and ensure that the receiver and cables connected to the receiver will be fully recessed to avoid interference with the battery:

The wires leading to the battery pack, and the pack itself, emit electromagnetic noise that is generated by the speed controller when the motor is turned partly on (but not fully on).

If you wish to be able to later change the crystal to a different frequency, consider rotating the receiver so the crystal is exposed to the inside of the battery bay. Do not place the receiver directly in the nose, as a hard landing would cause the battery pack to impact the receiver.

Cut the necessary depth into the foam for the receiver to be at least flush with the surface when installed.

Route the antenna wire Use an X-acto knife to cut a 1/4” deep antenna wire slot near the leading edge of the wing; see the template for placing suggestion.

The antenna wire should be approximately ¾” away from the spar slot, which allows the later



use of 1.5” wide filament tape to cover both the spar slot and the antenna slot.

Push the antenna wire into the slot using a large flat bladed screwdriver. Do not cut the excess wire; just let it hang loose beyond the wing tip. Leave a little antenna wire slack in the receiver bay to allow later servicing of the receiver, its crystal and connectors.

Servo cutouts You have several placement options for your servos. Templates are supplied for the standard placement technique, which requires no servo extension cables. Using the standard technique, the supplied Templates #4 and #5 serve as a servo placement guide. Cut the servo openings from the top.

However, we recommend that you install the servos further outboard in order to control the elevons nearer their center points, resulting in better control of the elevons when the elevons are aerodynamically stressed (twisted) during high speed operation. This is highly recommended for the 42 inch or shorter wingspan design in order to ensure better high speed control. Note that one or both of the outboard servos will likely require servo extension cables.

If you wish, you can install the servos from the bottom of the wing, then cut a hole or slot through the wing, to allow the servo control horn, located on the bottom side of the wing, to connect to the elevon control horn located on the top side of the wing on the elevon. This method results in less control rod exposed above the wing surface, however the procedure is more difficult because you need to cut an accurate hole in the foam that is large enough to stay clear of the control rod.

Follow the same procedure as above, except install the servos outboard. You will require a servo extension cable for at least one of the servos (in particular, the servo that is located farthest from the receiver). Outboard installation results in better control of the elevons, particularly during high speed flight. Place the

servo near the spar slot so you can use the existing spar slot for routing the servo cable. Do not install the servo beyond the point where the short outboard spar begins, in order to avoid balancing problems.

To determine where to place the servo cutout on the wing top surface, determine the servo placement on the bottom side, then drill a hole in the spar slot, through to the top side.

Top side shown:

Use the hole as a guide to assist in placing the servo template outline on the top side.

In order to avoid radio glitch problems, do not route the servo wires in the same slot as the antenna wire. Instead, use the pre-cut spar slot for your servo wires.

If using a servo other than the Hitec HS81 style, use the servo itself as the outline but place the servo so that the control horn is in the correct position.

Cut the foam slightly undersized to allow a firm press fit of the servo. Use an X-acto knife, or a Dremel motor tool with a small router bit attached.



If using a Dremel tool, you can apply blue masking tape around the perimeter of the servo opening, to use as a routing guide. Also, wrap blue tape around the router bit as a depth marker. Use a vacuum cleaner to pick up loose EPP foam as you cut.

Install servos Wrap both servos with a layer of blue masking tape around the body of the servo, to protect the servo from glue and glue fumes. Apply a few drops of polyurethane glue, epoxy or silicon glue (electronics-safe RTV silicon glue is desirable but not required) to the servo bay, then push each servo in place, while routing the servo wires through the holes previously prepared in the foam. Apply tape and possibly weights, as needed, to hold the servos down while the glue sets.

One of the servos is located on the wing half opposite that of the receiver. In order to connect its servo cable to the receiver you need to run it across the battery bay. To hide the cable, make a 1/4” inch deep cut across the bottom of the battery bay, and push the cable (or cable extension if used) into the slot.

Secure the motor in the tube Wrap masking tape around the motor until the motor is a snug fit in the tube. A very snug is particularly important if using a high performance motor such as the Mega or Astro, to ensure the motor case does not spin. If you wish, you can apply a small amount of silicon glue to the inside of the motor tube before sliding the motor inside.

If using a Speed 400 type motor, orient the motor so that its two ventilation slots line up with the slots in the motor tube.

Cut a ¼” deep slot into the foam, along the inside edge of the battery bay, from the motor tube to the receiver, to accept the speed controller’s 3-wire servo cable. Push the cable into the slot.

Wait 12-24 hours for the silicon glue to harden, before attempting to power the motor.

This is a good time to recheck the electrical system and servo arm positioning.

Covering preparation If desired, you can fill cosmetic foam damage, the carbon spar slot, and holes using common premixed white drywall spackle, generally available at home improvement stores.

The Red Devil brand (Ace Hardware) works well because it remains somewhat flexible after it dries.

Clean up the surface using a slightly damp sponge.

The spackle comes premixed with water and ready to use. Make sure it is water-based to avoid melting the foam.



Filament taping and covering In general, you finish the wing by applying 1 ½” wide filament tape to form the battery bay enclosure, and then more filament tape is used to strengthen the wings. You follow up with either colored tape, using the colors of your choice (recommended for minimal weight), or using a wing covering material that has a low shrink temperature such as Ultracote. In either case, you must be careful to avoid warping the wing structure.

For best flight visibility, we recommend that you use a dark color for the bottom of the plane, and a light color for the top of the plane. Apply the lighter colors first, for the most attractive appearance.

Before continuing, vacuum all dust and debris from your work area, foam core beds, and foam wings.

While taping the tops and bottoms of wings, keep the wing cores resting inside the original foam core beds to reduce the chance of wing warping.

Filament tape is almost fully transparent, so it photographs very poorly. To make the filament tape placement easily visible in the photographs, we used blue masking tape instead. Certainly you must use filament tape for your plane!

Full covering Use this procedure if you are covering the entire wing with tape4; this method offers maximum plane durability. In general, finishing tape or other wing covering is applied to the top of the wing first because it is generally desired to tape the top surface using a light colored material for optimal plane visibility; the dark colored material that is applied to the bottom will overlap the light color at the edges, resulting in an appearance that is more attractive than when you place light colored material on top of dark. 4 The most qualified wing taping expert in your home is probably whoever has proven to be best at wrapping the neatest gifts!

First review the precautions regarding the use of Super 77 Adhesive Spray, at the beginning of the assembly instructions.

When applying filament or color tape, do not stretch the tape or apply much tension. You only need enough tension to prevent tape wrinkles when laying the tape down. Otherwise you risk warping the wings.

Procedure; filament taping You apply 3M 77 Spray Adhesive to the wing surface prior to filament taping. Before spraying:

• Mask the exterior motor tube

• Mask the receiver

• Rotate the servo arms until they are under the wing surface and mask both servo arm slots with a small piece of masking tape

Spray a light coat of Super 77 Adhesive spray to the bottom side and edges, and let the spray dry about 2 minutes to allow most of the acetone in the adhesive to evaporate. Make sure you have sprayed the wing tip ends as well as the leading and trailing edges, in order to ensure that the tape that is later applied to it bonds well.

Use filament tape to complete the battery bay pocket and the battery bay strap. See the photos for details.

Refer to the photos that follow.

Run two pieces of filament tape across the battery bay on both sides of the receiver as shown. The gap between the two strips of tape should be at least 1” wide.



Leave enough filament tape sticking up to allow them to loop together in order to encapsulate the battery compartment.

Close the loops (see the next photo).

Run a long strip of filament tape from front to back of the wing root, in and out of the battery bay as shown.

Seat the long strip into the middle of the bay for the full length of the bay, and up the inner front wall.

Loop the filament tape that sticks out in front, around and on top of the front filament tape loop, forming a secure battery pouch:

Run two strips of filament tape across the wing, aligned on top of the filament tape pocket and loop created in the prior step:

Trim back the rear strap so its width is approximately 1 inch. The purpose of this step is to provide sufficient clearance for the battery to slide into the bay:

Cover the rest of the bottom nose surface with filament tape. Cover the long spar slot with filament tape.



Run filament tape alongside both long outside edges of the battery bay, all the way from the front to the rear of the plane. Note that this results in covering the receiver with tape.

The following photos show how the remaining filament tape is applied. Taping varies slightly, depending on where the servos have been located. In general, you do not want to cover the servos with filament tape, so you can access each servo later without cutting the filament tape.

Apply filament tape along the long edges of both wings.

The photo shows how the tape can be applied with only the leading edge touching the tape. Next, carefully roll back the rest of the tape surface until it fully contacts the wing leading edges.

Apply filament tape to the trailing wing edges using the same technique.

Cut vertical slits in the tape to accommodate the airfoil curvature of the wing tips. Then fold the tape around the corners.

The finished wing perimeter:

Apply additional lengths of filament tape as shown in this view of the bottom side; it is best to apply the tape when wings are resting in their bed, to minimize warpage:

The next two steps can be skipped, unless you wish to further harden the wings to improve crash resistance further. If you do choose “wing hardening”, mask the servos, and spray 3M



adhesive to the areas of the wing that will be taped.

Wing hardening; bottom side: Add more filament tape as shown in the next photo.

Wing hardening; top side. Add two stripes of filament tape as shown. Also note the additional tape wrapped around the nose leading edge in order to harden the nose against impact:

Procedure; Covering Note: When applying colored tape, cut the tape using a very sharp (new) X-acto knife blade.

Covering the top surface Rotate servo arms so they are inside the wings. Mask the servo bays, then coat the top surfaces of the wings with 3M 77 Adhesive Spray, and let the wings dry about 5 minutes. Run a stripe of blue masking tape on the top surface, offset about a half inch from the wing center chord, in order to offer an edge that facilitates trimming the covering tape that is applied later (see photo below).

For each stripe of covering tape, cut an oversize length of tape, and hold it taut but not stretched, above the area to apply it. Align the edge of the first tape stripe along the wing trailing edge. Align subsequent tape stripes along the edge of

the preceding stripe of tape, and then shift the tape slightly as you gently lower it so it overlaps the prior stripe by 1/8” to 1/4".

After taping one top wing half, gently run an X-acto knife along the blue masking tape edge, and then carefully remove the excess tape by pulling the blue masking tape off, in a direction parallel with the wing surface:

Next, apply blue masking tape in preparation for taping the opposite side, then tape the other wing half using the same methods:

Use the same basic technique to cover the bottom, except as required to accommodate the battery bay.



Covering the bottom surface Apply blue masking tape for the trim reference, placing it along the edge of the battery bay:

Tape one of the wing halves, beginning at the trailing edge. Let the tape extend all the way across the battery bay:

Cut and fold the tape into the battery bay. Avoid cutting the filament straps that are used to restrain the battery:

Before taping the remaining wing, apply the blue masking tape, this time on the opposite edge of the battery bay:

Apply cover tape to the remaining wing, resulting in completely hiding the battery bay.

Cut and fold the covering tape into the battery bay. Apply additional covering tape inside the battery bay, for uniform appearance:

Do not apply covering tape to the front (leading) edges of the wings yet; this will be done after the elevons and servo-covering racing stripes are installed.

After covering the bottom, cover the front edge of the wing with a stripe of colored tape on both wings; preferably a dark color such as the color chosen for the bottom of the wing.

Attach the battery bay cover flap and Velcro Flip the clear plastic battery bay cover flap upside down so that the writing printed on it reads backwards.

Then cover the flap with your choice of colored tape.

Since the flap is slightly wider than the 2” colored tape, you need two stripes of tape, slightly overlapping.

Use scissors to cut the final shape of the battery flap, using the outline printed on the plastic as a guide.

Peel the adhesive backing off of a ¾” square of soft fuzzy (loop) Velcro, and apply it to the inside of the flap (the un-taped side), at the spot indicated with dashed lines.



Cut a piece of mating Velcro, without removing its adhesive backing, and attach it to the top of its mating Velcro on the battery cover flap:

Lay the flap over the battery bay, and shift the flap far enough to the rear in order to cover the battery bay. Center it on the bay. Note that the flap is slightly narrower than the battery bay opening, in order to accommodate battery cooling (the battery can become quite warm during flight).

Attach the flap to the nose of the plane using filament tape:

Hide the filament tape by covering it with a piece of colored tape.

If the battery pack does not already have it, apply a Velcro strip (the strip that consists of miniature hooks) to the full length of the battery pack, down the center line of the pack.

Insert the battery pack into the battery bay, Velcro side up, but do not plug the battery into the speed controller cable.

Cut two strips of the mating Velcro strips so they fit in between the battery pack straps (and on top of the battery, mating with its Velcro). Loosely attach the strips to the mating Velcro on the battery pack, with the peel-off adhesive side UP.

When finished, the Velcro arrangement should appear as shown in the next photo.

Remove the adhesive backing from all three Velcro pieces.

Ensure the battery and its Velcro are aligned in the center of the battery bay.

Pick up the end of the battery flap, and apply slight tension to the battery bay flap, while swinging the flap down into place, against the wing bottom. Apply pressure over each Velcro piece. The two Velcro pieces situated on top of the battery will adhere to the flap Velcro, and the Velcro piece on the flap will adhere to the wing body. Carefully lift the flap back up, and the result should be similar to the photos below. Then remove the battery.

Sand and trim the elevons Construct a sanding block from a flat piece of wood, double backed carpet tape and sand paper. You can attach coarse (such as 150 grit) sandpaper on one side and fine (such as 220 grit) sandpaper on the other side.

A supplied 1/8 inch thick, 3 inch wide sheet of balsa has been pre-scored lengthwise with a knife; fold and separate the balsa sheet along this score line; these two pieces are your elevons.

While holding the elevons together, sand their edges until they are identical.



Tape an elevon down to the edge of a tabletop.

Sand the edge of each elevon until their end view profiles match the profile shown below. Note that all sanding occurs on the bottom side of the elevon; the top side remains flat:

Remember that the two elevons need to be prepared as mirror copies of each other (they are not identical copies).

Place one of the elevons where it will belong on the wing (flat side up, and wide end is outboard). Trim the outboard end of the elevon to match the angle of the wing tip:

Trim the inboard elevon ends at an angle of approximately 45 degrees, and providing at least ¾” of clearance from the propeller:

Cut, trim and sand the winglets Choosing from the patterns supplied in Templates #6, #7 and #8, cut 1/16” sheet balsa to the desired shape. Make two winglets.

Sand and round the edges. Fine sand the surfaces with #220 or #320 sandpaper.

Taping the elevons and winglets Vacuum the smoothly-sanded elevons, then apply 3M 77 adhesive spray to the top and bottom surfaces of each elevon; allow to dry 5-10 minutes.

Prepare a very clean table work area, so you can lay down a partly sticky elevon and not have it pick up debris.

Lay the lighter colored tape across the top of the elevon (the flat side), overlapping the edges by at least ¼”.

Flip over the elevon.

Use an X-acto knife to trim the tape overlap to approximately ¼”.

Fold the tape around the edges, trimming the corners as necessary.



The bottom side of the elevon is the side where most of the sanding took place. Tape the bottom side with the darker colored tape, without overlapping beyond the edge of the elevon. Place the edge of the first stripe of tape along the trailing edge (non-hinge) edge of the elevon.

Use an X-acto knife to trim the rest of the elevon perimeter, so the finished elevon appears as shown:

Rub top and bottom surfaces of elevons using a folded paper towel or clean rag, on a flat surface, to ensure tape adheres completely.

Smoothly sand and vacuum the winglets, then apply 3M 77 adhesive spray to the top and bottom of each winglet; allow to dry 15 minutes.

Then use the same taping techniques as used when taping the elevons.

Attach the elevons Here we show you how to use filament tape as the elevon hinge. There are alternative ways to hinge elevons, for example see the web site www.yourzagi.com.

First apply the filament tape to the top hinge edge of the elevon, with some overlap over both ends. Align the elevon hinge edge with the centerline of the tape:

Trim excess tape following the edges of the two ends of the elevon.

When aligning the elevon to the wing, make sure the outboard (tip) edge is inset from the wing



edge approximately 1/8” to prevent the elevon from rubbing against the tip winglet. The following picture shows a finished elevon and hinge, with the appropriate elevon wingtip inset:

Attach each elevon to the wing, by holding the elevon at a roughly 45 degree downward angle, slowly sliding it down against the entire wing trailing edge until the hinge tape just touches the trailing wing edge.

While maintaining the 45 degree angle, fold down the hinge tape, starting from the middle of the elevon.

When finished, there should be minimal to no gap between the elevon leading edge and the wing trailing edge, and the elevon should hinge freely +/- 45 degrees.

Tape racing stripes and leading edge At this point, you may wish to place racing stripes, using holographic film or colored tape on the top side, over each servo, and all the way back, over the top of the hinge and elevon. This helps hide the servos and servo control rods. If you choose to use holographic film, you can improve its adhesion to the wing surface. Remove its protective adhesive backing, then spray a wet coat of 3M 77 adhesive on the film’s adhesive side, then wait a few minutes before

applying. Make sure you cut open a slot for the servo arms. Then use dark tape to tape the leading wing edges.

Elevon control rod installation Loosely position the elevon control horn on the elevons, parallel to the centerline of the wing, behind the servo arms. A piece of masking tape can be used to mark the position, to ensure the control rod extends straight back from the servo.

Orient each control horn as shown in the photo so the two screw holes are positioned as shown:

Incorrect placement will result in one of the two holes being very close to the edge of the balsa wood; the corrective action is to swap the two control horns, as they are mirror-symmetrical.

Mark the screw holes with a Sharpie fine tipped pen:

Drill the screw holes, 1/16” or slightly larger in diameter.



Screw the nylon clevis towards the midpoint position of the threaded end of its servo control arm, to allow for control arm fine tuning adjustment.

Attach the clevis/control rod assembly to the outermost hole in the elevon control horn.

The next steps are best performed with the radio system powered up to ensure the servos are in the correct neutral position.

You can either use the Z-bend method or the clevis method to attach the control rod to the servo control horn.

The solderable clevis approach reduces possible slop and binding that might be encountered if using the Z-bend.

Connect the control rod to the top hole in the elevon horn:

When determining the correct length of the control rod, verify that the servo arm is in its neutral position. Also, the elevon should be in its neutral position, which is approximately 0.25” up, measured at the outboard elevon tip, as shown in the photo below:

If using the solderable clevis method (recommended), connect the solderable clevis to the elevon horn, then rest the control rod on top of the clevis.

Mark and cut the control rod to the correct length to accommodate the clevis, with the elevon angle set to the neutral position, as shown in the photo:

Cut the control rod at the marked point; the Dremel tool with a disk cutoff wheel attachment is used below to accomplish this:

Thoroughly clean the cut end of the control rod using Scotch Brite or fine sandpaper. Tin coat approximately ¼” of the rod end using rosin-core solder. Note that the rod absorbs a lot of heat so you need to ensure it gets hot enough. Tin the interior of the metal clevis with a coat of solder. Then solder the pre-tinned clevis to the pre-tinned rod. Remove excess solder.

If using the Z-bend method, mark the bend position on the rod, and bend the control rod 90 degrees, at two places, forming a Z, cut off the excess control rod, and insert the bent rod through the servo control horn. You will have to expand the diameter of the servo control horn hole to accommodate the rod diameter.

Connect the finished control rod assembly to the servo horn. If using HS81MG servos, use the middle hole of the supplied dual-horn type servo control arm. Enlarge the servo hole as necessary.

If the servo control horn hole diameter is too small, and you used the solderable clevis, you can install the metal clevis partway into the hole, then carefully heat up the clevis with a solder iron until it melts itself into the control horn hole. Do not jiggle the clevis while heating or cooling, in order to prevent the hole from becoming oversized. The ideal fit has no slop, yet pivots with no friction.



Next slightly bend the control rod, near the servo, to accommodate the curvature of the wing and to ensure that the linkage does not bind when moved to the extreme positions.

Connect the soldered clevis side to the servo arm; if using HS81 style servos, use the second hole from the end of the horn:

Connect the control rod nylon clevis to the top hole in the elevon hole.

Install the propeller onto the motor In order to use the supplied propeller in a “pusher” configuration, the propeller must be reversed. Remove the propeller from the black hub, reverse the propeller, and reinsert the propeller into the hub. When finished, the lettering on the propeller should be on the same side as the spinner (and readable when standing behind the plane). Also note that the actual prop color and marking information may vary.

Press the propeller onto the motor shaft. A common problem is not pushing the propeller far enough onto the shaft. Here are a couple of tips:

1. Slide a piece of wire into the propeller hub, and mark how far the wire went into the hub. Transfer this mark to the motor shaft, so you can tell when you have fully installed the hub onto the shaft.

2. Air trapped inside the hub makes it more difficult to install the hub onto the shaft. You can poke a pinhole into the end of the

hub to allow the air to escape, prior to installing the hub onto the motor shaft.

Attach the winglets Attach three pieces of double-backed carpet tape to both wing tip ends of the finished wings.

Inspect the paper template you used to create the winglet; the dashed lines indicate how the winglet should be attached to the wing tip, in relation to the airfoil cross section. Remove the backing from the tape, and apply a winglet to the wing tip. Repeat for the opposite wing.



Flight control system adjustment Connect up the receiver, speed controller and servos inside the plane, if you haven’t already.

Secure the plane so that the propeller has no chance of hitting anything (organic or inorganic), and the propeller thrust will not cause the plane to slide.

Set all the transmitter trim controls to their neutral position.

Turn on the transmitter. Program your transmitter so that channels 1 and 2 are set in Elevon mode (or equivalent).

Plug the battery pack into the speed controller battery cable.

Confirm that the elevon throw directions are correct. When you pull back on the stick, both elevons should go up, and when you push forward on the stick, both elevons should go down. If functionality is reversed, you need to unplug the battery pack and swap the servo connectors for channels 1 and 2 of the receiver.

Once you have the up/down (elevator) control orientation correct, move the stick straight to the left. The left elevon should go up, and the right elevon should go down. If functionality is reversed, you need to program your transmitter so that channels 1 and 2 are both set to the REVERSED mode.

Confirm that the elevon throw and trim amounts are correct.

With the elevator (up/down) and rudder (left/right) trims all set in the center position on your transmitter:

(1) make sure the servo control horns are both sticking straight up,

(2) fine tune your threaded nylon control arm clevises so that both elevons have ¼” up elevator as measured at the outboard elevon tip (in flying wing parlance, this required up elevator amount supplies the wing with “reflex”).

Next, adjust the maximum throw of the elevons. A common mistake is to have too much elevon travel; this will result in unpredictable and frequently uncontrollable flight behavior.

Start by ensuring that each control rod is installed in the middle hole of the servo control horn, and the opposite end of each control rod is installed in



the top hole of the elevon control horn.

When you pull straight back on the stick, both elevons should go up 3/8” to 1/2". You should observe opposite throw when pushing the stick all the way forward. When you move the stick all the way to the left, the left elevon should go up 3/8” to 1/2”, and the right elevon should go down the same amount. You should observe opposite throw when moving the stick all the way to the right.

If necessary adjust the control rod/control horn leverage until you obtain the desired travel throw. If your transmitter supports “adjustable travel volume” or an equivalent feature, use this feature to fine-tune the elevon throw.

Re-verify that the elevons are at the correct angle when the stick is in the neutral position.

Finally, confirm that your control system does not bind, particularly when the servo horns are extend to their maximum positions. Maximum elevon throw is accomplished by moving the stick to each of the four extreme joystick corner positions. If necessary, bend the control rod just enough to prevent binding against the wing surface, then readjust the elevons for the neutral position.

Balancing the aircraft The wing must be balanced properly in order to achieve stable flight. Measure the balance point back from the nose of the plane. The balance point depends on the wing span; please refer to the Specifications section at the beginning of this document for the initial balance point.

Relocate the battery pack in the battery bay until the required balance point is achieved. To be conservative, you can set the balance to a point ¼” closer to the nose; if the balance point is too far back, this will result in a plane that is unstable and unflyable. If the balance point is too far forward, an excessive up elevon neutral point (control stick pulled toward you) will be required to keep the nose from dropping during flight. In this mode, the plane’s flight will be stable, but it will be harder to land slowly owing to reduced up elevon control.

Once you have determined the battery pack balance point, cut a small piece of EPP foam of the correct size to fit in front of the battery pack inside the battery bay, to fill in the gap in front of the battery (if any). Insert the foam piece into the battery bay, ahead of the battery.

Wingspan modifications You can reduce the wing span by shortening the wing tip ends. This can be done after the standard 48” wingspan plane has been built and flown. This generally results in a plane that flies faster and is more maneuverable, at some penalty in glide performance. Note that reducing the wingspan in this manner results in the balance point moving forward toward the nose. Winglet templates have been supplied to accommodate wingtip chords that correspond to 42” and 36” wingspan. Mark the wing for desired wingspan using Templates #1 and #2 as guides, then cut the foam with a sharp X-acto knife, or use your favorite cutting tool. Saw through the carbon spar in the wing. Then carefully block sand the wing ends so they are squared and smooth.

The 42” wing span offers excellent soaring as well as excellent aerobatics performance.



General flying precautions • The plane is capable of high speed flight. Under no circumstances fly the plane where there is

a risk of hitting and injuring people or causing property damage. • Join the Academy of Model Aeronautics (AMA) in order to provide insurance, information

regarding safe flying practice, and modeling news. You may be required to join AMA in order to fly in certain fields.

Academy of Model Aeronautics 5161 E. Memorial Drive Muncie, Indiana 47302 Phone: 1 (765) 287 1256 Fax: 1 (765) 289 4248 http://modelaircraft.org

Battery pack tips A new Nickel Metal Hydride (NiMH) battery pack typically does not reach its peak performance until after 3-5 charging cycles. This is because the cells in a new battery pack each are initially at a different level of charge.

Battery lifetime is largely determined by the degree to which the battery pack has been thermally stressed, i.e. overheated during battery discharging or charging:

• Use a “peak charger” instead of a timer-based charger, to reduce the possibility of overcharging the battery.

• Make sure your charger has been configured or programmed to limit the charging rate of the battery pack you intend to charge.

• Reduce the amount of time you run full throttle. • Follow the instructions provided with the peak charger. In general, NiCad batteries should be

charged at no greater than twice their capacity, and NiMH batteries should be charged at no greater than 1X their rated capacity. Lower charge rates will tend to increase the lifetime of the battery pack.

• For NiMH battery packs, some manufacturers recommend a full discharge cycle after about 10 charge cycles to reduce battery “memory effects”. If your charger supports a discharge-charge cycle, consider using it for this purpose.

• Wait for a battery pack to cool off before beginning a charge cycle. • If the battery pack is warm to the touch when the charge cycle completes, you can “top off” a

battery pack by letting it cool off, then applying another charge cycle. • Obtain several packs, and rotate them, allowing spent packs to cool before recharging.

You can make a simple battery pack cooler for field use, with a 12 volt DC fan and some 2 inch diameter PVC pipe. A number of plans are available on the Internet. At www.google.com conduct a Google search for “battery cooler”.



Flight checklist Checkoff

Item

If you are a beginner, your odds of crashing can be greatly decreased through the use of model airplane flight simulator software. An excellent freeware version can be found on the internet. At www.google.com, conduct a search for “Flying Model Simulator”.

If flying in an AMA sanctioned flying field, you must adhere to their rules and regulations regarding use of the field, radio frequencies, and whether you require an AMA and/or club membership card.

Always perform a visual check to see if there are any other R/C fliers in the vicinity, and if so, make sure there is no frequency conflict.

Set the throttle stick to the off position, and turn the transmitter on.

Install the battery pack into your plane, and plug it into the speed controller, keeping clear of the propeller.

Make sure all controls are working properly.

Pull the control stick toward you to confirm both elevons go up. Move the stick to the left and confirm the right elevon moves down and the left elevon moves up.

Check the transmitter trim settings.

While holding the plane securely, slowly turn on to the throttle to confirm that the propeller power system is working correctly. To test the radio system and speed controller, lower the transmitter antenna (unextended), turn the throttle up about 20% (in order to maximize RF noise generated by the speed controller), and slowly walk back away from the plane, with a friend holding the plane. You should be able to control the elevons reliably for at least 50 feet; actual distance depends on the quality of the radio system, and placement of the speed controller, motor and battery in relation to the receiver and receiver antenna location.

If testing a new plane, re-check the balance point before launching.

Before flying, ensure your transmitter antenna is fully extended, and the receiver antenna is not wrapped around the winglet.

There are several ways you can launch the plane; please refer to the Launching section on the next page. Conduct a flight test on flat land, and with a light breeze. In most cases you should launch the plane straight into the wind.

Conduct glide tests, in order to set your trims correctly. Correct the flight path using your transmitter. See the Troubleshooting section for further help.

The glider test passes when the plane flies straight ahead, with a gentle sink rate and landing.

Flying continuously at full throttle will heat the battery and motor up quickly and reduce the flying time. Flight time can be considerably extended by flying at partial throttle or with throttle off some of the time.



Launching There are a number of imaginative ways of launching the Unicorn; two popular methods are shown here.

The Pizza Toss 1. Hold plane as shown with throttle off.

2. “Wind up for the pitch”.

3. Launching.

4. Liftoff. Then apply throttle.

The Discus Launch We found this technique to be slightly more difficult than the pizza toss.

1. Grab the wingtip, ahead of the winglet. Note fingertips are on top surface, thumb on bottom. 2. Apply at least 75% propeller throttle, then begin gently swinging the plane around you.

3. When plane is pointing in the desired direction (away from people and into the wind), and in a stable attitude, release the plane, in a horizontal or slightly upward angle, and wave “bye-bye”…



Troubleshooting Problem Suggestions Airplane is very difficult or impossible to control

Perform a radio range test, with the transmitter antenna un-extended and the airplane on the ground. You should be able to control the plane successfully from a distance of at least 30 -50 feet. Apply partial power to the motor, and then verify that you have smooth control of the elevons while the motor is running. If this test fails:

Your receiver or antenna may be too close to the battery, motor, or the wires connecting the battery to the motor.

Your balance point is too far back. Move battery pack forward. Your receiver may be of the “single conversion” type which is

more vulnerable to interference than the “dual conversion” type. Replace the receiver.

Your transmitter or receiver may be defective.

The radio range test passes but the airplane remains impossible to control

Center of gravity is too far backwards. Move the battery pack towards the front (see Specifications for proper balance point).

The novice may tend to fly the plane too fast, making it more sensitive to control. Also the novice can fly too slow which can lead up to a stall.

Too much elevon surface movement. Reduce the total amount of elevon travel.

Excessive up elevon is required to keep plane in level flight

Center of gravity is too far forward. Move the battery pack towards the rear (see Specifications for proper balance point).

Aircraft stalls frequently (pitches up, stops, then drops)

Push forward (up) on your transmitter’s elevator trim in order to lower your aircraft’s elevons and increase air speed.

The plane was not launched fast enough and doesn’t have enough energy (altitude and/or speed) to recover.

Aircraft drops to the ground when launching

You need more down trim on the transmitter’s elevator control (to raise your elevons).

You might not have enough energy in your throw. Your balance point is too far forward.

Aircraft veers off to the left or right when transmitter stick is in the center position

Adjust the aileron trim controls on the transmitter until level flight is achieved.

If excessive aileron trim is required, check for warped wing. You may be able to untwist the wing by simply twisting the entire wing in the opposite direction.

Battery runs out of charge quickly

New NiMH battery packs typically require several discharge-charge cycles before achieving peak performance.

Your charger may not be configured properly to fully charge the



battery pack. One possible remedy is to charge the pack, let the battery pack cool down, then charge it a second time to top it off.

Battery pack is defective. This may be due to charging the battery pack at an excessive rate (the pack will overheat).

Aircraft appears to have poor climbing ability even with full throttle

Ensure propeller is not installed backward. You must configure the propeller with the manufacturing lettering viewable from the rear of the plane. The unlettered (smooth) side should face the motor and the wing.

Propeller falls off Propeller was not fully seated on the shaft. See instructions for tips. Also you may need to replace the propeller hub once this happens, because the hub plastic tends to melt when the shaft spins within it.

Warranty Unicorn Ventures guarantees this kit to be free from defects in both workmanship and material at the date of purchase. This does not cover any components or parts damaged by use, misuse or modification. In no case shall Unicorn Ventures’ liability exceed the original price of the purchased kit. Since Unicorn Ventures has no control over the final assembly, no liability shall be assumed for any damage resulting from the use by the user of the final user-assembled product. By the act of using the final user-assembled product, the user accepts all resulting liability.

Credits Thank you very much Bill Sammons (Thor4944 at www.rcgroups.com) for all your enthusiasm, videos and still photos (as taken from the ground and on board the Unicorn)! Thanks to Hans Spiller for his extensive feedback regarding overall design and documentation, and Bill Henley, President of the Seattle Area Soaring Society (SASS), for his winglet design suggestions. The man who many consider to be Pacific Northwest’s flying wing expert authority, Bill Kuhlman, ( www.b2streamlines.com ) contributed his expertise regarding flying wing performance optimization. The Unicorn was fine tuned based on feedback from numerous other model aircraft enthusiasts in the Redmond Washington area, many of whom are members of the SASS ( www.reddata.com/sass ). Many thanks to all the “beta” testers who helped improve the quality of the final products; you know who you are… Mark Chamberlain Shoreline, WA



Customer photos

Andrew Olson; Oregon

Electro, Virginia Beach VA Scrambleon, Exeter, CA

Jack Forkner, Copperopolis, CA

Mike Downey, GA Tomegun, NV

ZippoGeek Sarj, Canada RandyK1, Zion, IL



Customer comments

Why didn't I get a Unicorn years ago - another flight first thing this morning – amazing. Best fun I've had in ages.

…all I can say is WOW this wing can fly! I fly it every chance I get.

Hey! I received my Unicorn in the mail on Friday. Built it on Saturday and maidened her today. I ran 8 packs through her and I don't think I could have been happier with the results.

The durability is amazing.

Just maidened the unicorn today and man what wing.

What a kick to fly! It is like a Carbon Falcon on steroids! it penetrates the wind very well which is exactly what I wanted. I am one happy camper and waiting for tomorrow to fly some more

As an engineer, I appreciate clean and simple design, and the Unicorn definitely lives up to my expectations.

Hi, Mark. I think we're finally going to get some pictures of the crazy fun that has been going on at our club with the Unicorns. A digital movie camera and a digital still camera are both suppose to show up at the field this Thursday night. We are up to 13 wings now. We keep a list at the field of who is using what channel so

new guys don't use a channel that is already being used. Our record so far is ten in the air at once.

Man does it go! Can't get enough.

This thing doesn't seem to want to land though ....it glides forever - & then some

You know I haven't had it all that long, but I've flown more since building the Unicorn than I was able to fly ALL YEAR when I had just the gas planes

During one 20 minute-plus flight a guy behind me says, "Do they ever come down?" THIS is what I had in mind when I got back into flying R/C.

I can’t say how much I appreciate your product—I ruined two planes prior to this trying to learn on my own and now the unicorn has me flying like a pro—(well, at least I can pick it up after a bounce and go right back to

flying).

My wife says that since the birth of our children, I haven't had such a big smile on my face for so long!

I'm very new to flying, and to flying wings. I couldn't be happier with my Unicorn.

By far this wing is the most stable straight line flyer of my small fleet

Oh boy what a hoot - she went straight up (more thrust than weight!!!) and accelerated like a scalded dog in level flight!

It was 8:15pm when I had my first toss outside.....tossed it and it was gliding much different outside, was carrying much longer then I throttled up and that is when the fun began, (mmmmmmmmmmmmmmmm) that is

what it sounded like if there was a sound....I could barely hear it....VERY VERY VERY QUIET...I could not believe it.....It climbed like it had helium in it or something...wow.....I could not stop it from climbing.

I had a local police officer stop by and radar my flights. Avg speed 70mph.

Tears of joy were just behind my eyes as my boys (7 and 4 yrs.) looked on.

It flies great I think it will move to my favorite plane status.

Thanks Unicorn dudes!

36"CUTOFF FOR 36" WINGSPAN

CUTOFF FOR 42" WINGSPAN

42"

TEMPLATE# 1

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PYRIG

HT 2002

UN

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48" WINGSPAN

36"



42"

TEMPLATE# 2

CO

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HT 2002

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VENTU

RES48" WINGSPAN

TEMPLATE # 3BOTTOM VIEW

LEFT WINGRECEIVER

CUTOUT PATTERNCOPYRIGHT 2002

UNICORN VENTURES

EXISTING SPAR SLOT

ANTENNA SLOT, CUT 1/4" DEEP WITH XACTO KNIFE

RECEIVERCENTERLINE

CUTOUT RECEIVERAREA FROM

BOTTOM SURFACE

HITEC MICRO 555

FMA DIRECT EXTREME 5OR

GWSR4PH

5"

BA

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AIR

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AIRCRAFT LEADING EDGE

TEMPLATE # 4TOP VIEW

LEFT WINGHS-81 SERVO


UNICORN VENTURES

4 1/2"MINIMUM

ROUTE SERVOWIRE THRUSPAR SLOT,

TO RECEIVERB

ATT

ER

Y B

AY

ED

GE

SERVO

AIR

CR

AFT

CE

NTE

R C

HO

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EXISTING SPAR SLOT

THE DISTANCE BETWEEN THE

AIRCRAFT LEADIN

G EDGE AND

THE SERVO WILL V

ARY, DEPENDIN

G

UPON THE DISTANCE OF THE SERVO

FROM THE CENTER CHORD LINE

OF THE WING BECAUSE THE SPAR

SLOT ISN'T PARALL

EL TO THE LEADING

EDGE OF THE W

ING

TEMPLATE # 5TOP VIEW

RIGHT WINGHS-81 SERVO


UNICORN VENTURES

4 1/2"MINIMUM

ROUTE SERVOWIRE THRUSPAR SLOT,

TO RECEIVER

BA

TTE

RY

BA

Y E

DG

E

SERVO

AIR

CR

AFT

CE

NTE

R C

HO

RD

LIN

E

EXISTING SPAR SLOT

THE DISTANCE BETWEEN THE

AIRCRAFT LEADING EDGE AND

THE SERVO WILL VARY, DEPENDING

UPON THE DISTANCE OF THE SERVO

FROM THE CENTER CHORD LINE

OF THE WING BECAUSE THE SPAR

SLOT ISN'T PARALLEL TO THE LEADING

EDGE OF THE WING

TEMPLATE # 6WINGLET PATTERN48" 42" 36" WINGS

COPYRIGHT 2002UNICORN VENTURES

48" WING

42" WING

36" WING

assembly and flight manual - ep.yimg.comep.yimg.com/ty/cdn/unicornwings/manual.pdf · a new product...

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