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Radio Controlled Rocket Glider Kits

Interceptor III Rocket Glider Kit

The Interceptor III RC Rocket glider kit.  This is styled after the original Estes Interceptor rocket kit, but modified to be light weight and with a wing large enough to allow gliding.  It has a light wing loading giving it a very nice glide and easy/stable boost.  It comes with a plastic Interceptor nose cone, 2" white tubing for the body and depron wing and tail surfaces. The only hard part of the kit is cutting the slot in the tube for the wing after you join the two body tubes, however they come pre-marked for you.   You will need two 10 gram type servos, two 12"-18" servo extensions, a receiver, and a small 500mah single cell lipo battery.  You will need a transmitter with delta or elevon mixing.   Please refer to the notes on items needed for completion and flying, then read the instructions completely before starting assembly.  The assembly photos are for general reference but may not include every step in the instructions. If you want hardcopy to work from, all you have to do is click/drag/select and copy all of the text below the photos, open word and paste with "keep original format" and it looks exactly like it does online then you can print it.  

​CG location for rocket flight: Where the wing leading edge meets the strake.


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Welcome to the world of rocket boosted radio control gliders.  This is not a model for a novice RC pilot, but anyone who is comfortable with RC flying of a medium speed model should be fine.  Read through the instructions, look at the photos and be sure you understand the step before commiting to cutting or glue.

Interceptor III Rocket glider instructions

Identify all pieces, the kit should contain:

1  wing  taped together


1 wing spar(carbon fiber)


1 Nose cone


2 pushrods


2 control horns


2 vertical stabilizers


4 wingtip pods


2 Body Tubes


Motor mount

 

2 centering rings 


Velcro(for battery and rx/bec attachment)

2 Rail buttons with t nuts/screws or 1 Launch lug


2 landing skids

3M blenderm tape

Lead weight

Spare depron

Notes before starting:

Reference to CA+ means foam safe CA+, normal CA+ will melt the foam!  Normally you need to use accelerator to get the CA to set on the foam since there is nothing for it to soak into and activate.

You may use 220-320 grit sandpaper and a sanding block to slightly round the edges of the foam if you prefer that look.  It will not markedly impact the flight performance either way.  Be very careful and use a light touch, it is very easy to catch the foam on the edge of the paper and tear the foam.  Do any sanding before assembly.

Epoxy is not needed in this model.  Weight is critical and the model is designed for the thrust and flight loads.  Weight in the rear end is bad and will require additional weight in the front of the model.



Assembly:

  1. Glue a centering ring on the front of the motor mount about 1/8" from the end.  Make sure the notch in the ring slides over the motor hook.  Glue another centering ring 1.25" from the rear of the motor mount, again making sure the notch slides over the hook.  Use a lightweight glue and use it sparingly.
  2. Unfold the wing and glue it using CA+ at the taped joint, make sure it is flat. 
  3. Glue the spar into the slot in the bottom of the wing using CA+ then tape over using the blenderm tape.
  4. Join the two body tubes.  One tube will have the coupler pre-glued in place.  Glue the other tube onto the coupler.  Make sure the arrow marks on bottom of the forward tube lines up with the arrow mark on the bottom of the rear tube, this will make sure the wing cutout lines are aligned.  Use glue sparingly since you have to cut through the coupler for the wing slot.
  5. Carefully cut out the wing slot on the lines marked.  Lines are approx size.  Make sure to check the wing thickness and don't cut the slot too oversized.  Take your time and go slowly.  It's easiest to do this using a piece of angle aluminum to help keep the line straight.
  6. If using rail buttons, ​make a hole in the bottom of the rear of the body tube at the place indicated for the rail button and install it using the T nut.  Don't tighten down really hard, just enough to secure it. 
    Install the forward rail button on the mark indicated in the same manner.  If using a launch lug install this after radio equipment.

  7.  Test fit the wing into the slot carefully.  Sand or trim as needed for a good fit without dragging/damaging the foam.  You'll need to start by putting the wingtip into the slot, then rotating so that the wing goes in straight.  Sand the front or back of the wing slightly if you are having trouble getting it in the slot.​ Make sure the wing is centered in the body tube and glue using CA+ along the top and bottom on both sides.  use CA+ and accellerator.  You can squeeze the tube slightly as the glue sets to make sure it makes contact and doesn't have a gap.  
  8. Insert a pushrod into the outermost hole in each control horn, insert one from each side.  The pushrod should go into the inboard side of the horn.  Install a horn into the holes in each control surface, again with the pushrod on the side closest to the body tube.  Use CA+ and make sure it is glued well.  Once done, flip the model over and put some CA+ on the top where the prongs stick through the surface to lock it in place.
  9. Install the two vertical tails.  Sand the slots or tabs slightly if needed so that they fit.  Glue in place with CA+ and add a light fillet.  The angle isn't super critical as long as they are symmetric.
  10. Glue in the motor mount into the tail, it should stop against the fin tabs and be even or recessed slightly compared to the body tube.
  11. Using a tool make two holes for the landing skid and glue one just in front of each rail button.  Test fit on a  rail to make sure they are aligned and don't drag on the rail.  These help protect the rail buttons from landing damage.  Make sure the front skid isn't so far forward so that it doesn't interfere with the nose cone shoulder.
  12. Glue a wingtip pod on the top and bottom of each wingtip using CA+.  Make sure they are straight front to back and are straight up and down.  Sand lightly if needed.  Make sure the wing stays flat and isn't twisted when you glue them in place.  These help stiffen the wing tips.


The basic construction is now complete.

Radio Installation

Note:  Your radio needs to be configured for Delta mixing, this means that the servo arms will move the same direction during elevator stick movement and opposite for aileron stick movement.  Connect your servos to the receiver one in the aileron connection and one on the elevator connection and apply power.   Use a servo arm at least 9/16” long and with holes small enough that there won’t be slop with the pushrod wire when installed.  I use the hole furthest out on the servo arm, to maximize movement. On some servos there are a long two-ended servo arm, you can trim off one end if needed to get sufficient length.   Zero out any trim settings on the transmitter. The model once the motor has burned out is nose heavy and flying wings lose pitch authority when nose heavy so you want as much up elevator travel for trim/flare as possible.


  • Connect a servo to each pushrod, the servo wire should be closest to the center and the output shaft is outboard toward the wing tip.   If the wire is too tight, you can use twist an exacto knife in the servo arm hole to make it larger, but be careful and do not make it too large.  Once connected, tape each servo in place so that the control surfaces are centered.  Flip the model right side up and look at it from the rear.  Moving the transmitter stick back(up elevator) should move both elevons up.  Moving the transmitter stick to the right should move the right elevon up and the left elevon down.   If you can’t get the servo reversing to give you the right polarity try swapping aileron/elevator inputs to the receiver or turning the servos over and swapping the servo arms to the other side of the output shaft.  If that is correct, continue.
  • Flip the model upside down and supported.  The servos may be attached to the model using double back servo mounting tape(not included) or by directly gluing the servo to the wing with CA+ or a small amount of epoxy.  Double back servo tape can loosen over time and with exposure to heat, I prefer to glue the servo in place.  With the radio still on, put a small amount of glue on the servo, being careful not to get any near the output shaft. And set it in place on the model keeping the control surface centered.  Do the same to the other side.  Make sure the glue is set before continuing.  The servo and pushrod should be at 90 degrees to the hinge line so that it moves easily and fully. 
  • Flip the model back right side up.  Make sure the control surfaces are centered, use trims if needed.  Now measure the control surface movement.  Full elevator movement should be 1” in each direction, aileron movement should be 1/2" in either direction.  Since the model will be nose heavy, extra elevon movement helps to give sufficient authority during glide. 
  • If you have a flap/elevator mix you can program up elevator to a switch setting.  The model needs approximately  1/4” of up elevon during glide and slightly less than1/8" of down trim for boost.  If you can’t set the up elevator trim to a switch on your radio you’ll have to manually put in boost and glide trim which is hard to do while flying the model.
  • Attach a 12-18" servo extension to each servo.You just need to be able to route the wire to the front of the tube to attach it to the receiver.
  • Make a slot in the bottom of the wing/fuselage ahead of the coupler and pass the wires through to the inside and toward the front.
  • Attach the servo wires to the receiver and make sure they are going the right direction.  Tape down the servo wires and tape over the slot in the body tube.
  • If using a launch lug install it centered on the launch CG location in a spot such that the rod won't interfere or hit the wiring or servos and not directly on the bottom of the model so that it gets damaged on landing.
  • Use the included Velcro to attach the receiver 2" from the front of the body tube on the top(or enough to allow the wires to clear the shoulder of the nose cone). This allows you to be able to remove and replace the receiver if needed for repairs or for removing the servo wires. I attached the battery inside  nose cone on the shoulder.
  • Insert your heaviest loaded rocket motor into the motor mount
  • Support the model upside down at the balance point indicated for boost.  I use two pencils with the eraser pointed up and held in place with a small hand vice.  Place the model upside down on the pencil erasers on the balance point indicated in the kit spec sheet.  Use the included lead weight  to balance it either in the nose or tail as needed. Do not try to fly the model with it balancing it behind this point.  The adage is, a nose heavy model flies poorly, a tail heavy model flies once​
  • I used markings for the IntR/Ceptor from stickershock along with a few pieces of self adhesive vinyl trim cut to shape.  Mark at stickershock23 can create anything you wish. With the vinyl from stickershock23 it helps once applied to use a hair dryer on hot to soften the material and then push it down onto the model with a towel.  It helps it confirm and stick much better.   I put a 1.5-2" wide strip of trim vinyl or monokote to the bottom of the body tube, this helps keep the body tube from getting dirty/wet on landing, and helps aid orientation during boost. 
  • Use a  black sharpie to add panel lines if desired, I ran a fine line sharpie into all the panel lines in the nose cone and it really sets it off. You can use red wide sharpie for the wingtips or see the general instruction page for notes on painting. 
  • Re-install the receiver and battery


Flying:  See the Instruction/Information link at the top for flying instructions Note, my prototype needed a small amount of down trim on boost and as it gained speed arced back up vertical.  Be ready on the first few flights to keep the model straight till you have the trims set perfectly for boost and glide.