The original KADET SENIOR was designed in the mid-80's by Claude McCullough and shortly thereafter, it became a SIG kit. Claude put a great deal of thought into the KADET SENIOR design and came up with an R/C training aircraft that was just about perfect. As proof, it's safe to say that in the intervening years, the KADET SENIOR has been used to teach thousands of modelers to fly. In addition, the design has been used for many other applications as well as being "kit bashed" into any number of different configurations. The KADET SENIOR kit is still in production and remains a true model aviation classic!

Over the years, we've received a lot of questions about the KADET SENIOR. But of all the questions received here at SIG regarding the KADET SENIOR, the number one issue has been how to add ailerons to the wing. Even though the design was never intended for aerobatics, many modelers feel that with the addition of ailerons, the KADET SENIOR would become the "ultimate trainer". We have listened carefully to all these suggestions and comments and as a result, we are pleased to present the new KADET SENIOR ARF.

The ARF version of this great design retains all of the really good flying characteristics of the original SENIOR, but now features true "barn door" ailerons. To make the ailerons more effective, the dihedral angle has been reduced from the original design. To make the airplane IMAA legal, the wingspan has been increased to 80-1/4". The increased span also increased the wing area to a huge 1180 sq. inches! This means that the KADET SENIOR ARF is capable of carrying a lot of additional equipment, such as a lighting system for night flying, cameras, etc., and still retain a very favorable wing loading. The radio compartment in the fuselage is roomy enough for almost anything that you might want to carry aloft. All of this capability still only requires a typical .40 or .46 2-stroke engines or a .40 - .65 4-stroke engines to fly the airplane.

The KADET SENIOR ARF kit has been expertly covered with AeroKote™, featuring either transparent blue or transparent red to show off the beautiful structure. The wing has been designed to be a 2-piece assembly, allowing easy transportation to and from the field and simplified storage. The beautiful fiberglass cowl allows you to customize the required openings for your particular engine and muffler set-up. The landing gear system is very forgiving, making even the worst landings look just a bit better.

We urge you to read this assembly manual completely before assembly. Familiarize yourself with the parts and their assembly sequences. The successful assembly and flying of this airplane is your responsibility. If you deviate from these instructions, you may wind-up with problems later on. The KADET SENIOR ARF is certainly a suitable R/C model for beginning modelers.

However, it is important to understand that if this is your first R/C model, you will need to find and use a qualified R/C flight instructor to test fly the airplane and teach you how to fly it. If this is your first radio control model airplane, DO NOT attempt to fly it without a qualified instructor.


Radio Equipment

The KADET SENIOR ARF requires a standard 4-channel radio system and five standard servos. We have used and can highly recommend both the Airtronics™, RD-6000 Sport system and the Hitec™ Flash 4X system. Both of these affordable and reliable radio systems offer all the features you'll need for this and the many other R/C aircraft in your future. For reference, this assembly manual shows the installation of the Airtronics™ RD-6000 Sport radio system with Airtronics™ #94102 standard servos. In addition, you'll need two 24" aileron servo lead extensions and an aileron servo Y-harness for connection to the receiver.

Engine Selection

Engine choices for the KADET SENIOR ARF are many. Choosing the right engine is important and should be based on your intended end-use for the airplane. For example, if your KADET is going to be used as a trainer, then, either a .40 - .46 2-stroke engine or a .40 - .65 4-stroke engine would be about ideal. Actually, any of these engines will fly the KADET quite nicely and well within its intended flight envelope.
2-stroke engines need not be bearing equipped but from experience, engines with bearings tend to be a better long-term choice. We have found that the Irvine .40, .46, and .53 2-stroke engines are ideal for the KADET SENIOR ARF. These engines are extremely reliable, very user-friendly, and quiet. Whatever engine you choose, take the time to carefully break it in according to the manufacturer's instructions. A good running, reliable engine is a minimum requirement for the enjoyment of this or any R/C model aircraft.

Covering Material

Your KADET SENIOR ARF has been professionally covered using AeroKote™. This material is well known for its ease of application, light weight and consistency of color. If you live in a dry climate, you may notice that some wrinkles may develop after removing the covered parts from their plastic bags. This is perfectly normal in low humidity climates.
is covered with SIG AeroKote™

#SIGSTL100 White and

#SIGSTL010 Transparent Red or
#SIGSTL050 Transparent Blue

Your model was built and covered in a part of the world, which has relatively high humidity and therefore, the wood was likely carrying a fair amount of moisture. When exposed to drier air, the wood typically loses this moisture, dimensionally "shrinking" in the process. In turn, this may cause some wrinkles. However, wrinkles are easy to remove by just using a hobby type heat iron.
We suggest covering the iron's shoe with a thin cotton cloth, such as an old T-shirt, to prevent scratching the film. The iron should be set to about 220oF - 250oF (104o C - 121oC). Use the heated iron to lightly shrink the material - do not press on it. Then, lightly iron the material back down to the wood. You can also use a hobby-type heat gun to re-shrink the covering but you must be careful around seams or color joints. Re-heating seams may cause them to "creep", making them unsightly. This is especially true with the KADET SENIOR ARF and its 2-color trim scheme. You must also be careful when using a heat iron or heat gun when working around the windshield and side windows - heat will distort this clear plastic material.

Required Tools

For proper assembly, we suggest you have the following tools and materials available:

  • A selection of glues - SIG Thin CA, SIG Thick CA, SIG Kwik-Set 5-Minute Epoxy and SIG Kwik-Shot CA Debonder
  • Screwdriver Assortment
  • Pliers-Needle Nose & Flat Nose
  • Diagonal Wire Cutters
  • Small Allen Wrench Assortment
  • Pin Vise for Small Dia. Drill Bits
  • Hobby Knife with Sharp #11 Blades

  • Small Power Drill With Selection of Bits
  • Dremel® Tool With Selection of Sanding & Grinding Bits
  • Scissors
  • Sandpaper
  • Heat Iron & Trim Seal Tool
  • Masking Tape
  • Paper Towels
  • Alcohol and/or Acetone For Epoxy Clean-up


Complete Kit Parts List

The following is a complete list of all parts contained in this kit. Before beginning assembly, we suggest that you take the time to inventory the parts in your kit. Note that the hinges for the rudder, elevators, and ailerons are in place but not yet glued. Please also note that the bolts and nuts required to mount your engine to the motor mounts are not included and must be purchased separately.

Basic Aircraft Parts
1Fuselage 1Wing Panel Set With Ailerons in Place with Unglued CA Hinges 1Horizontal Stabilizer & Elevator Set With CA Hinges 1Vertical Fin & Rudder Set with CA Hinges
1Fiberglass Cowl With Four #3x8mm PWA Mounting Screws


Main Landing Gear Assembly
23-3/4” Dia. Main Wheels 13-1/4” Dia. Nose Wheel 2Main Landing Gear Wires -
4.5 Plated Wire
2Nylon Landing Gear Retaining Straps
4#3x16mm PWA Screws 2 4.5mm i.d. Plastic Wheel Spacers 2 4.5mm i.d. Wheel Collars With Set Screws
Nose Gear Assembly
1Formed Nose Gear Wire -
4mm Plated Wire
1Nylon Nose Gear Steering Bracket 1Nylon Nose Gear Steering Arm with 4mm Brass Insert & M3x6mm Setscrew 4M3x30mm Bolts
4M3 Flat Washers 4M3 Lock Washers 14mm i.d. Plastic Wheel Spacer 24mm i.d. Wheel Collars With Set Screws
Fuel Tank Assembly
1Fuel Tank Body -
320cc (10.8 oz.)
1Rubber Stopper 1Metal Clamp - Front 1Metal Clamp - Rear
1M3x18mm Bolt 1Metal Clunk Fuel Pick-Up 1Length of Fuel Tubing for inside of tank 1Aluminum Tube -
3mm o.d.x60mm
1Aluminum Tube -
3mm o.d.x50mm
1Aluminum Tube -
3mm o.d.x40mm
Motor Mount Assembly
2Filled Nylon Motor Mounts (1) Right, (1) Left 4M3x20mm Mounting Bolts 4M3 Lock Washers 4M3 Flat Washers
SIG 2” Diameter Spinner Assembly
White With Inserts and Mounting Screws - P/N SIGSP201

Hardware Mounting Package
2Servo Hatch Cover/Mounts - White Plastic - (1) Right, (1) Left 8#2x8mm (5/16”) PWA Screws - Servo Hatch Screws 4#2x6mm (1/4”) PWA Screws - Aileron Servo Block Screws 4Hardwood Servo Mounting Blocks -
1Balsa Fuel Tank Retainer -
21/4-20x1-1/2” SIG Nylon Wing Bolts 4Nylon Control Horns -
(2) Ailerons, (1) Elevator,
(1) Rudder
2Nylon Control Horn Bases -
(1) Elevator, (1) Rudder
4M2x20mm Bolts - Rudder & Elevator Control Horn Mounting 4#3x16mm PWA Screws - Aileron Control Horn Mounting

1Hardened Aluminum Blade Main Wing Joiner -
1Rear Wing Locating Pin, Steel - 1/8" dia.x2-3/8" 2Balsa Dowel Pushrods -
10mm dia.x85cm (33-1/2")
2Inner Nylon Pushrod Tubes - 1/8" o.d.x16-15/16" (Throttle & Nose Wheel Steering)
4Heat Shrink Tubing -
17mmx50mm (Wire Pushrod Retainers)
7Threaded R/C Links -
(2) Ailerons, (1) Rudder, (1) Elevator, (2) Throttle, (1) Nose Wheel Pushrod
2Rudder & Elevator Pushrods -
2mm dia.x102mm with "Z-bend"
2Rudder & Elevator Pushrods, Threaded one end -
2mm dia.x30cm
2Aileron Pushrods, Threaded one end with "Z-bend" -
3Fully Threaded Studs -
2mmx20mm (Nose Wheel pushrod at servo, Throttle pushrod, both ends)
1Nose Wheel Pushrod, Threaded one end with "Z-bend" -
1Molded Clear Plastic Side Window Set -
(1) Right, (1) Left
1Decal Set, 5"x18", 1-color (white) - P/N SIGDKM258ARF 1Assembly Manual



The wings have been designed and made to be a 2-piece system, joined by the main aluminum blade joiner at the spar box location and a steel locating pin at the rear. This joiner system has proven to be very tough and easy to use. An obvious benefit, especially with a model of this size, is the fact that the wing panels can be easily transported or stored, requiring a minimum of space.
You may want to consider using a little 5-minute epoxy to permanently install the aluminum blade joiner and the rear steel locating pin into one of the panels. Doing this could prevent accidentally losing these parts - your call.

Note that the wing panels in your kit box come with the ailerons in place but not yet permanently hinged. Hinging the ailerons will be done in the very first step. To protect the covered parts of your model from unnecessary damage, we suggest covering your work surface with protective foam or an old blanket. For the following steps you will need two standard aileron servos, two 24" servo extensions, and a Dual Servo Y-Harness for your particular radio system.


Remove the aileron from the wing panel and pull out the four CA hinges from their slots. Note that the supplied hinges have a die-cut center slot that can be used to accurately place and center the hinge equally into both the wing panel and the aileron. To do this, use scrap cardstock and a pair of scissors to cut some "wedges". These should be wide enough at one end so as to not pass through the hinge slot cut-out.

Press the four hinges into the slots in the wing panel up to the hinge slot cut-out. Place a card wedge into each hinge and then press the aileron in place onto each exposed hinge half, up to the card wedges. Slide the aileron left or right to center it within the wing panel aileron bay. The hinges are now in proper position for permanent mounting.

Flex the aileron downward, exposing the hinges between the wing and aileron. Hold the aileron in this position with a piece of masking tape to free up both your hands. For CA hinges, we always recommend using a fine-tip applicator on the glue bottle to better control the flow. Remove the card wedge from one of the hinges and carefully apply four (4) small drops of CA glue to each side of the exposed hinge.

Remove the card wedge from the next hinge and again apply four drops of glue to each exposed hinge edge. Repeat this process for the remaining hinges. Remove the tape holding the flexed aileron to the wing panel and flex the aileron in the opposite direction, again using masking tape to hold the aileron in this position. Turn the wing panel over and apply four drops of CA glue to each exposed edge of each hinge, exactly as before. Remove the tape holding the aileron, returning the aileron to its centered position. Because it takes a little time for the CA glue to fully wick through the surface of the hinge and surrounding wood, allow at least 10 minutes before flexing the aileron. Clean-up any excess glue drops or smears on the covering material with SIG CA Debonder.

After sufficient time has passed, flex the aileron firmly up and down on the wing panel to create free and easy movement. We also suggest pulling on the aileron at each hinge location, making sure all four hinges are firmly in place. Repeat this procedure for the remaining wing panel and aileron.

Turn the wing panel over on your work surface to reveal its bottom side. Note the aileron servo opening. This opening will house one of the two required aileron servos. Also, note that a short length of scrap wood with a string tied to it is visible within this opening. This is one end of the string that will be used to pull the aileron servo lead through the wing.


The opposite end of this string is found - tied to another scrap piece of wood - at the round opening at the bottom, center of the wing panel.


The aileron servos are now mounted to the molded plastic servo hatch covers. Begin by installing the rubber grommets and brass eyelets (supplied with your radio system), into each servo. Use epoxy or slow CA glue to mount the 5/16" x 1/2" x 13/16" hardwood servo mounting blocks to the inside surface of the hatch cover, using the servo itself for spacing. Be sure to locate the servo with its output arm directly over the center of the molded aileron pushrod fairing as shown. Allow the glue to set.

With the mounting blocks positioned and glued in place, remove the servo. Use a hand-held power tool, such as a Dremel® Tool and a tapered sanding drum bit to open the ends of the plastic pushrod fairings where the pushrod passes through from the servo arm to the aileron horn. Prepare the remaining servo tray in the same manner.

With the two servo trays now prepared, use the mounting screws provided with you radio system to secure the two aileron servos to the mounting blocks on each servo tray. To avoid spitting the mounting blocks, pre-drill the screw holes with an under-size drill bit.


The final preparation step for the two servo trays is to drill two 1/16" dia. holes in each servo tray, one directly beneath both hardwood servo mounting blocks. Use four #2 x 6mm (1/4") selftapping screws provided to secure the mounting blocks.

Note that the aileron servo mounting trays are "mirror images" of each other - in other words there is a left and a right servo tray. Correctly oriented, the molded pushrod exit fairing on each servo tray is located inboard, toward the center of the wing.


Plug a 24" servo extension lead into each aileron servo plug and secure these connections with plastic tape. Reach into the aileron servo bay in the wing panel and gently break loose the scrap piece of wood with the string tied to it. Remove the scrap piece of wood and securely tie the end of the string onto the end of the servo lead extension.

Now, break loose the other piece of scrap wood - with the opposite end of the string tied to it - from its location at the inboard end of the wing panel. Lightly pull on the string to route the servo lead cable through the wing panel and out through the inboard hole in the wing panel.

Pull the servo lead fully out of the exit, leaving no slack in the aileron servo bay. Remove the string from the servo lead and use a piece of tape to hold the lead to the wing for now.


With the aileron servo mounted in place, carefully fit the plastic aileron tray into the aileron servo bay in the wing panel.
Since it is easily viewed through the top of the wing, align the servo accurately within the servo bay opening. Use pieces of masking tape to hold the servo tray in its final, correctly oriented position. Using the pre-drilled mounting holes in the servo tray as guides, drill four 1/32" dia. guide holes through the sheeting in the bottom of the wing.


Mount the servo tray to the wing using the provided #2 x 8mm (5/16") Phillips/Washer Head self-tapping screws. Mount the opposite servo tray in place into the remaining wing panel in the same manner. Because the servo tray will have to be removed briefly in the next few steps, remove the screws and set them aside for now.


From the kit contents locate two nylon control horns, four #3 x 16mm (5/8") Phillips Head screws, two wire aileron pushrods - 2mm x 80mm (3-1/8") and two metal R/C links.

You will also need the aileron servo output arms that you intend to use. We like using the 4-arm type, choosing the arm with the longest length. You will likely have to use a small drill to open the holes in the servo arm in order to accept the 2mm (.070") dia. pushrod wire. Slip the "Z"-bend end of the wire pushrod into the outer hole in the servo output arm and press the output arm onto the servo with the arm facing 90o down into the fairing molding in the servo tray, as shown. This is the desired "neutral" position for the aileron servos with the radio system on. Thread the metal control link onto the end of the aileron pushrod, about halfway, allowing for equal adjustment in either direction.

Carefully remove the trays and aileron servos from the servo bay - laying the tray on the wing next to the servo bay opening. With the servos accessible, now is the time to check their movement and centering, using the radio system. Connect the servo leads to the Y-harness and plug the harness into the aileron receptacle in the receiver. Connect the battery and turn the system on, along with the transmitter. First, check for the correct direction of servo travel. Reverse the servo direction, using the transmitter, if necessary.

Next, check the centering of the servo arms, with the transmitter aileron trim lever in neutral. Remember that the servo output arms should be facing directly down into the molded fairing in the servo tray, at 90o to the servo. Remove and reposition the output arms as needed to achieve this positioning.

With these issues addressed, install and tighten the servo output arm screws in both servos. Carefully re-install the servo trays back into the aileron servo bay openings in both wing panels and secure in place with the screws. In preparation for the next step, use a couple of small pieces of masking tape to hold the ailerons in place at neutral to the wing panels.


The nylon control horns are now installed into the bottom leading edge of both ailerons. These nylon horns are molded with a flat base and two mounting holes. These two holes will likely have to be drilled out to .070" (a 5/64" drill bit works fine) to allow the two mounting screws to pass freely. Do this now.

Place one of the wing panels upside down on your workbench. Spread the R/C link arms and attach one of the nylon control horns, using the outer-most hole for now. Visually line-up the wire pushrod with the wing ribs, so that it is exiting straight out of the servo try fairing. With the wire now aligned, place the base of the nylon control horn onto the aileron. Screw the R/C link in or out to get the front of horn base lined up with the leading edge of the aileron. Use a pencil or sharp point to mark the location of the two mounting holes in the control horn. Remove the control horn from the R/C link.

With a 3/32" drill bit, drill two holes into the aileron, at the marks just made - do not drill all the way through the aileron, just far enough to accept the screws. Use two of the #3 x 16mm (5/8") screws to mount the control horn to the aileron. Repeat this procedure on the opposite aileron. With the control horns in place, adjust the metal R/C link on the wire pushrod until it fits into the outer-most hole in the control horn.


To secure the metal R/C link to the nylon control horn, cut a short length (about 1/4") of medium fuel tubing and slip it over the R/C link, onto its two arms. Attach the R/C link to the control horn and then slide the fuel tubing forward to the connection. This ensures that the R/C link will not be easily dislodged from the control horn - a very good safety practice for all such connections.


Remove the pieces of tape holding the ailerons in the neutral position. Use the aluminum blade and the rear steel pin to join the wing panels together.

Plug the aileron leads into the Y-harness and plug the single Y-harness lead into the receiver aileron channel receptacle, along with the power switch and battery. Turn on the transmitter, followed by the receiver. Now test the action of the ailerons. The movement should be smooth with good centering back to neutral. Also, again make sure that the ailerons are moving in the correct direction (looking at the wing from the rear, moving the transmitter stick to the "left" aileron position should cause the left aileron to move up and the right aileron to move down). If the movement is in the wrong direction, use the servo-reversing feature on your transmitter to reverse the action of the aileron servos.


Test fit the assembled wings to the fuselage. The tab that is formed by the two panels at the center, leading edge, fits into the cut out in the windshield former.

Make sure the two aileron servo leads are in the cabin. At the rear, the wing nests onto the fuselage, aligned over the cabin. Use the two 1/4-20 x 1-1/2" nylon wing bolts to secure the wing in place to the top of the fuselage. This is the way the wing mounts to the fuselage and the way that you will assemble it at the flying field. Remove the wing from the fuselage and set it aside for now.


The 320cc (10.8 oz.) fuel tank supplied with this kit is now assembled. We suggest using a simple two-line fuel system in this airplane. The carburetor fuel line is connected to the fuel tank pick-up line, or "clunk" line. To fuel or de-fuel the tank, this line is pulled off of the carburetor and attached to your fuel pump. The second fuel line is the pressure/vent line. When filling the tank, this line is used as the overflow to indicate a full tank. After the tank is filled, this same line is then connected to the engine's muffler pressure nipple, providing manifold pressure to the tank. Note that the rubber stopper for the tank has two holes all the way through it. Use these two holes for the aluminum fuel lines.
Also, note that the correct position for the fuel tank, inside of the fuselage, is with the off-center stopper hole toward the top.

Gently bend one end of the aluminum overflow tube upward to 90o, to just reach (but not touch) the top of the tank. To prevent any blockage in this tube at the top of the tank, sand its end at a 45o angle. Adjust the length of the internal silicon fuel tubing to allow free movement of the fuel pick-up weight, or clunk, inside the fuel tank at the rear. Install and start the center compression bolt.

Insert this assembly into the neck of the tank, pushing it fully into position. Align the internal overflow tube with the top of the tank. Secure the assembly in final position by tightening the center compression bolt firmly. Slip two 6" lengths of medium fuel tubing over the aluminum fuel lines and identify them as "vent" (overflow) and "carb" (fuel pick-up) with small pieces of tape. This helps later when connecting the fuel lines to their proper locations.



The KADET SENIOR ARF is a large airplane. For this reason, we have found it more convenient to work on the fuselage subassemblies without the tail group in place. The first of these subassemblies will be the installation of the engine, followed by the fuel tank.
The KADET SENIOR ARF is nicely powered with the 2 or 4-stroke engine sizes suggested. The airplane does not benefit from being over-powered. Doing this tends to put undue stress on the airframe without any real gain in performance. This airplane was always intended to "fly on the wing", not on excessive power. Note that the engine installation for either 2-stroke or 4-stroke powerplants is basically the same. The only differences being in the throttle arm locations on the carburetors and the muffler locations.

The factory-installed throttle pushrod tube in the fuselage has been placed to exit the firewall on the right side of the fuselage. Note that it is not yet glued in place and is removable. This positioning is typical for the throttle arm location on most 2-stroke engines. If you plan to use a 4-stroke engine, it may be necessary to relocate this throttle pushrod tube over to the left side of the firewall to line-up with typical 4-stroke engine carburetor throttle arms. This is easy to do, using a long 3/16" dia. drill bit to drill a new hole (aligned with the engine throttle arm) through the firewall and the second fuel tank support former behind it. In this case, the throttle tube would be installed, passing through these two new holes and into the servo compartment.

The engine is mounted in the upright position, providing easy access. For reference, the engine shown in these instructions, is an Irvine .46 2-stroke engine - just about the perfect amount of power for this model.


In this instruction sequence the engine and fuel tank will be installed. You will therefore need the following:
  • Engine (with muffler removed) - not included
  • Assembled fuel tank
  • Balsawood Fuel Tank Retainer - 5/16" x 3/4" x 4-9/16"
  • Glass-filled 2-piece motor mounts
  • 4 - M3.5 x 20mm bolts
  • 4 - M3.5 lock washers
  • 4 - M3.5 flat washer
  • 2 - 6" lengths of medium fuel tubing - not included
  • 4 - 6-32 x 1" socket head bolts - not included
  • 4 - 6-32 lock nuts - not included
  • 4 - 6-32 flat washers - not included
  • Silicon sealer (common kitchen & bath type) - not included


Use the four M3.5 x 20m bolts, lock washers and flat washers to mount the two glass filled motor mounts to the firewall. Do not tighten the bolts because the motor mount arms must be able to slide left or right on the face of the firewall to fit the engine case.

Place the engine on the two motor mount arms. Spread or close the motor mount arms as needed to get them against the sides of the engine, with the mounting lugs flat against the top of the mount arms. Use your hand to hold the motor mounts against the engine and slide the engine/motor mount assembly left or right against the firewall, visually centering it to the round fuel tank hole. When it looks about right, snug up the four 20mm motor mount bolts to hold the two arms in place, without over-tightening them.

With the motor mounts now held in place, use a ruler and slide the engine on the motor mounts to place its propeller bearing face 4-1/4" from the surface of the firewall.

This is the distance that engine should be bolted to the motor mounts. Use a center punch or large diameter sharpened nail to mark the engine mounting bolt hole locations onto each motor mount. Remove the engine and remove the motor mounts from the firewall.


If using the recommended #6-32 bolts and lock nuts to mount your engine, use a 5/32" dia. drill bit for the four required mounting holes - two in each motor mount arm, at the marks just made.The best way to do this is by using a drill press so as to drill the holes perpendicular to the top of the motor mount arms. However, if you have a good eye, these holes can also be drilled fairly accurately by hand.


Assemble the engine to the motor mount arms, using the recommended #6-32 mounting bolts and lock nuts. The engine/motor mount assembly is now bolted to the firewall. We suggest using a little thread lock compound on the bolt threads to keep them firmly in place. Again, visually center the mounts on the firewall, using the round tank opening for reference. Tighten all bolts firmly.


With the engine in place, the fuel tank can be installed. Fish a length of common string through the round fuel tank opening at the front of the firewall, all the way through the tank compartment and out into the cabin area. The string will be used to direct the tank and fuel tubing into the fuselage. Using the end of the string at the cabin area, tie it securely to the ends of the two fuel lines.

Apply a generous bead of silicon sealer around the neck of the fuel tank (remember the correct orientation of the fuel tank within the fuselage is with the neck of the tank "up" when viewed from the front). Insert the fuel tank into the fuselage from the cabin area, lightly pulling the string at the front and pushing the tank in place from the rear. The fuel tank fits onto a pre-cut "cradle" former within the nose. Pull the fuel lines through the firewall hole and press the neck of the fuel tank firmly into the round hole. Pressing the tank in place spreads the sealer, which keeps fuel out of the hole.

The balsawood fuel tank retainer (5/16" x 3/4" x 4-9/16") is now pressed in place in the fuselage at the rear of the fuel tank, between the fuselage sides. Press and hold the retainer against the back of the fuel tank and apply a couple of drops of thin CA glue to each side of the part, where it contacts the fuselage sides. The tank is now held in place. If it ever needs to be removed, the retainer can be easily broken free and the tank can then be pulled out from the rear. Remove the string from the fuel lines.

With the engine now mounted (without the muffler) and the fuel tank installed, the fiberglass engine cowl can now be trimmed to fit and mounted.



From the kit contents, locate the fiberglass engine cowl and the package of four #3 x 8mm PWA mounting screws. The cowl needs to be opened up to accept the engine head, carburetor and to clear the muffler. The idea is to do this as neatly as possible, keeping the nose of the model looking "clean". We suggest using a Dremel® Tool and a sanding drum bit to make this opening as tidy as possible.

Begin by first using a ruler to measure the diameter of the spinner molding at the front of the cowl and dividing the number in half and making a pencil mark at the top, center of the spinner molding.

Now, place the cowl on a flat surface, nose up.

Use a 90o triangle and the pencil mark just made to draw the approximate centerline of the cowl directly onto its top surface. This centerline will be the reference for drawing and then, opening the cowl to accept the engine head, carburetor, etc.


To accurately develop the initial required hole in the cowl, take simple centerline measurements directly off of the engine, using a ruler. This is easy if you use a scrap piece of wood clamped vertically on the engine, using the prop washer and nut to hold it in place as shown. At the front, measure the distance from the front of the carburetor body - mark that point in pencil onto the cowl. At the rear, measure the distance to the back of the engine head, again making a mark onto the cowl.


For initial width of the engine opening, measure the width of the engine head at the rear and the width of the carburetor body at the front. Again, transfer these marks onto the top of the cowl in pencil. The cowl should now be marked sufficiently to make the initial opening.


Use a Dremel® Tool or similar powered hand-tool and a small drum sanding bit to begin opening the hole in the top of the cowl, within the pencil marks - ALWAYS wear a good dust mask and eye protection when working with power tools and fiberglass parts. Be aware that there are no "rules" when creating openings for engines in plastic or fiberglass cowlings. The idea is to "sneak up" on these openings, continually trying the opening until it fits over the engine. Once it is able to be installed over the engine and placed correctly on the model, then the idea is to continue modifying the opening to provide access to and clearance for the muffler and carburetor needle valve. Using a soft pencil to mark the various required modifications in the opening, directly onto the cowl, tends to give the best, most accurate results.


With the cowl opening now made with clearance for the muffler, muffler bolts and needle valve, the cowl can be accurately mounted to the fuselage. We suggest leaving a 3/32" - 1/8" space between the front of the cowl and the spinner backplate. This spacing leaves room to make any needed thrust adjustments later on. Start by placing the cowl over the engine and onto the front of the fuselage.

From the kit contents, locate the bag containing the white 2" SIG spinner assembly. Remove the molded plastic adapter rings (four different sizes). Try each ring until you find the one that fits your engine propeller shaft. It should fit smoothly with no play. Cut that particular ring from the molding and slip it onto the prop shaft. Now, fit the spinner backplate onto the prop shaft and over the adapter ring, all the way to the rear of the shaft, against the engine. To hold the backplate in place, mount a propeller onto the shaft and hold it in place against the spinner backplate using the engine propeller washer and propeller nut.

With the above parts now in approximate position, use a scrap piece of 3/32" or 1/8" balsawood between the back of the spinner backplate and the cowl to achieve the required spacing. Use pieces of tape to hold the parts together in this position. At the rear of the cowl there are four small pre-drilled mounting holes which should now be positioned against the fuselage sides. Use a couple more pieces of tape to firmly hold the cowl accurately to the fuselage. Use a 1/16" drill bit to make a guide hole through one of the cowl mounting holes and the fuselage side. Install one of the #3 x 8mm PWA screws into the drilled hole and screw it in place - do not over-tighten the screw.

Check the overall fit of the cowl and make any adjustments needed with tape to hold it in place. On the opposite side of the fuselage, drill another 1/16" guide hole using the hole in the cowl for centering. Install another #3 x 8mm PWA screw into the hole. Repeat this process for the remaining two cowl mounting holes. Remove the tape. The cowl should now be accurately held in place with the mounting screws.

Now that the cowl fits accurately to the fuselage, engine and the spinner backplate, remove the four cowl mounting screws, the propeller and spinner backplate and the cowl. Use 220 grit sandpaper to smooth the edges of the cowl cut-out and remove any remaining pencil marks with alcohol. Set the cowl and the other parts aside for now. Later, when the nosegear strut is mounted to the firewall, another cut-out will have to be made. Instructions covering this are provided in the correct sequence.



Before mounting the stabilizer and vertical fin, there are three openings at the top rear of the fuselage that must be opened. Two of these openings will accept the bottom tabs of the fin and the other is the rudder pushrod exit. Use a hobby knife and a sharp #11 blade to remove the covering from these openings.


2. The rudder is now hinged to the vertical stabilizer (fin) and the elevators hinged to the horizontal stabilizer (stab). The technique for hinging these surfaces is exactly the same as it was for the ailerons, earlier in these instructions. Cut and install the card wedges into the center of each hinge and join the surface together with its mate. NOTE: Be sure to carefully align the top of the vertical fin with the top of the rudder. This allows free movement of the rudder over the horizontal stabilizer.

Flex the surface downward about 1-1/2", holding it in this position with a piece of tape. Remove a wedge from one of the hinges and apply four drops of thin CA glue to each exposed edge of the hinge. Move on to the next hinge and repeat the process. When one side is finished, turn the assembly over and repeat the procedure on the opposite side of each hinge. Remove the tape and let the surface return to neutral. Allow at least 10 minutes to pass before flexing the surface. These two assemblies are now ready for installation onto the fuselage.


The horizontal stabilizer and elevator assembly is glued in place first. The stabilizer must be accurately centered onto the uncovered stabilizer saddle at the rear of the fuselage. This is easy to do using a yardstick. Pin the stab in place onto the fuselage stab saddle. Use a yardstick to then measure the distance from the outer trailing edge corner of the stab to the rear edge of the wing saddle. Then, take the same measurement on the other side of the fuselage. The two measurements should be identical or within 1/8" of each other. This is the same procedure that you will use when gluing the stabilizer in place.

To help visually align the stabilizer correctly, mount the wing to the fuselage, using the two 1/4-20 x 1-1/2" nylon wing bolts in the kit. Place the model on a flat surface and orient it to allow you to view the airplane from the front and back from a distance of 10 feet or so. Mix a batch of 5-minute epoxy in sufficient quantity to cover the fuselage stabilizer saddle. Spread the glue evenly over the exposed wood of the stabilizer saddle.
Carefully set the stabilizer in place onto the saddle and apply a little pressure to spread the glue. Pin the stabilizer to the saddle and quickly use the yardstick to check that it is square to the fuselage. With the stabilizer squarely in place and pinned, view the airplane from the front and rear. The stabilizer should be equally aligned with the wing - not tilting one way or the other. If it is tilting, correct it using pins or weights. Allow the glue to set with the stab in this position. After the glue has set, remove the wing and the pins holding the stab in place. Alcohol can be used to clean and remove any glue that may have oozed onto the fuselage or stab.


The vertical fin and rudder assembly is installed next. First, trial-fit the vertical fin in place to the fuselage and horizontal stabilizer. If the tabs on the bottom of the fin need any trimming to allow a good fit, do this now. Next, hold the vertical fin in place and use a sharp pencil to trace around its forward fairing, where it extends forward of the stabilizer onto the fuselage.

Remove the fin and use a hobby knife and sharp #11 blade to cut and remove the covering from just inside of the pencil marks just made.

For visual alignment purposes, reattach the wing and again place the model on a flat surface, allowing you to view it from a distance. Use 5-minute epoxy to apply glue to the bottom of the vertical fin, including the tabs that fit into the slots in the stabilizer and fuselage. Press the fin and rudder assembly in place, applying a little pressure to make a good glue joint. While holding the fin in place, use alcohol and a paper towel to smooth the glue along the joint. Use two pieces of masking tape to hold the aligned fin to the fuselage and horizontal stabilizer. One piece extends from the top of the fin to the tip of the stabilizer and the other extends in the same way to the opposite side. Use the tape to hold the fin perfectly vertical and adjust the tape as needed to hold it in position and to avoid it tilting one way or the other. With the structure held in place, allow the glue to set. After the glue has set, remove the tape and the wing from the fuselage.