1:48 18mm Blackbird RC RG Instructions

The 1:48 18mm Blackbird RC rocket glider kit

The Blackbird RC Rocket glider kit is designed after the outstanding reconnaisance aircraft flown from the 1960’s through the 1990’s. It comes with white BMS tubing for the body and engine nacelles and 6MM Depron wing and tail surfaces. The body tubes are pre-slotted for the wing and tail surfaces, the elevons are pre-hinged and spar slot is pre-grooved. Rail button holes are pre-punched and the kit comes with rail buttons. You will need two 8-11 gram type servos, a receiver, and a small 500mah single cell lipo battery and 2 lightweight 12″ servo extensions. You will need a transmitter with delta or elevon mixing. Foam safe CA+ is the only correct glue to use for all construction on this model. Any other adhesive will add weight in the wrong place, and reduce flight performance. Please refer to the General instructions for all kits tab above, then read these instructions completely before starting assembly. For 18mm composite D-13 motors with no ejection charge and plugged forward closure. Wingspan 16″, length 27″(1/48 scale) weight 7-7.5 oz rtf. High quality cut vinyl decals available, you need to select the 1:48 scale size. Here

CG location for rocket flight: 5/8″ back from the the front of the nacelle tubes.

Note in the D-13 reloads if there is any white speckling on the propellent, use some coarse sandpaper to roughen up the inside of the grain slot before you load them, the white specks are oxidation and will make it harder to ignite the propellent. Load as in the directions just use the plugged closure at the front.

Unpacking your kit:

The kits are packed to protect them in shipping, but the contents are fragile so unpack carefully. Carefully cut the tape holding the tubes in the box, then unwrap/lightly cut the plastic wrap to free the tubes, the spar may be packed in the tubes and the baggie with the little parts and nose cone will be in the tubes as well. Carefully cut the tape holding the cardboard wing protector in the box and carefully remove it, don’t pull hard or bend it. Then carefully cut the tape holding the cardboard top piece to the bottom. There may be some sticky tape holding the cardboard to the bottom cardboard piece, carefully peel it being sure not to bend anything. Once the top cardboard is free you can see the foam wing/tail parts, there are little fragile pieces in here, so unwrap carefully. It may be best to use an exacto to lightly cut the plastic wrap and carefully remove it without cutting into the foam. Make sure everything is free before you remove the pieces to avoid breaking anything. Kits contain one or two scrap pieces for repairs if you damage anything in construction or flight, just cut and patch in a spare piece of the foam if needed using foam safe CA+. The tubes may look a bit smudged or have some gray marks, this is due to the aluminum angle I use for cutting the slots, if it bothers you you can use a soft eraser to remove it, but since it will be painted black, it won’t really matter.

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 an aileron controlled 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.

Identify all pieces, the kit should contain:

1 wing taped together

2 vertical stabilizers

2 forward chine curved sections

1 long slotted body tube with holes for rail buttons

1 short body tube

2 nacelle half tubes

2 control horns w/pushrods

Velcro(for battery and rx/bec attachment)

3M blenderm tape

1 coupler

Nose cone

2 Intake cone paper wraps

1 foam cockpit pieces.

motor tube

carbon spar

2 rail buttons/t-nuts and screws

Lead weight

spare depron for repairs and shimming for the motor mount install.

Assembly:

Look at all parts and understand what pieces go where.
Unfold the main wing and glue the taped joint.
Glue in the spar into the premade slot on the bottom of the wing and then tape over with blenderm tape. Also tape the center wing joint for extra strength.
You may use 320 or 400 grit sandpaper to round the edges of the foam before further assembly. Round all edges of the wing at this time except for the intake cones spikes and the forward wing which will butt against the nose/curved portions of the chines. Go slowly and take your time. Round the leading and trailing edges of the vertical stabilizers at this time as well.
Draw a line on the wing for aligning each engine nacelle. The line will go from the front inboard edge of the triangular intake shape on the wing back to the inboard notch on the wing trailing edge, the line just has to go back as far as the hinge tape. See photo for clarity.
Cut out the paper intake cone shrouds.
I rolled the paper shroud over a table edge several times to pre-curve it to making gluing easier. The printed side will go against the table top so that the glossy side will be visible when glued to the model.
Glue one side of the paper wrap onto the side of the wing triangle shaped intake so that the notch aligns with edge of the wing/intake. Glue so that the glossy side without printing will be visible. The wrap won’t go completely to the tip of the foam, that’s ok you will sand the tip to shape shorter after the paper cone is attached. Gently wrap the paper around and glue to the other side making a half cone and glue to the other side again aligning the notch with the front of the wing. Run CA on the inside corners and tip as well. Trim the foam tip at a slight angle to match the paper if there is any excess to make it look clean. Repeat for the other side. It may help to wrap a finger with seran wrap or a sandwich baggie to prevent your finger from sticking to the wrap when you hold it down for the glue to set.
Look at the two pieces of nacelle tubing. There is a left and a right. They are marked on the tubes and the slot for the vertical stab will be angled inward slightly. If you have these swapped the elevon won’t have proper clearance to move.
Glue the nacelle so that the front of the nacelle tube is even with the front of the wing next to the intake cone. Start gluing on the inboard edge along the line on the wing. IT IS CRITICAL the first edge is glued on the line otherwise the nacelles may not be straight and the vertical stabs will have an undesired rudder angle built into them!! Glue the other edge in place. You may need to squeeze the tube slightly at the front as you glue so that it lines up at the front, the tubes spread a bit after cutting them.
Repeat for the other side. Use accelerator to set the glue as you go.
Glue the two vertical stabs in place in the slots. The stabs angle inward, it isn’t critical the absolute angle just try to get both sides approximately the same. Reinforce the joint on both sides with a CA fillet on the inside and outside of the tube, use accellerator to set the glue before proceeding.
Glue the motor mount in place in the slot cut in the wing, make sure it is centered. I used two pieces of scrap foam under the wing near the motor cutout and then pushed the mmt against the table top, this provided the right spacing to center the motor tube, fillet top and bottom
Install the rail buttons in the pre-punched holes in the body tube. The T nut goes inside the tube, then a plastic washer, plastic collar and plastic washer go on the outside of the tnut shaft and held in place with the included screw. Make sure they are snug but don’t over tighten. The T nuts are bent to conform to the inside of the tube and not deform it make sure they are rotated correctly to conform properly and not deform the tube.
Glue the coupler into the end of the main body tube inserting about halfway. Check to make sure the coupler will fit or use a slower setting glue to give you time to adjust it. When set, glue the short tube in place onto the coupler.
Test fit and slide the slotted part of the body tube onto the wing from the front making sure it is centered at the rear and the rail buttons are on the same side as the spar(on the bottom) Once centered, tack glue the rear of the tube top and bottom and then glue fully along the body tube on the top to secure it in place. The tube tends to flatten once it is cut so you may need to pinch the tube slightly as you glue and use accellerator a bit at a time to make sure it stays round in the middle and makes contact with the wing. I tack glue a few spots along the tube to make sure it is straight and the wing stays flat, then do the complete joint. Flip over and glue the bottom of the tube to the wing. Do not deform or bend the wing as you glue the rear. Don’t glue the chine portions in place on the forward body tube yet, just the slotted portion of the tube!
Lay one side of the wing against a table. This is so that when gluing the chine to the forward body tube it will stay flat and aligned. You can use wax paper to make sure you don’t glue to the table top and make sure the body tube is slightly away from the edge of the table..
Tack glue the chines to the body tube on each side keeping them straight, then put a fillet top and bottom. If the chines don’t go all the way to the end of the tube thats ok, the chine portions on the nose cone will mate up with them when you glue them in place.
Tape the shoulder of the nose cone so it fits snug into the body tube, align the seams on the cone with the chines on the body tube so they will be hidden when you glue the curved portions to the nose cone.
Lay the curved chine piece flat on a table top the last 2″ of the curved chine sections to taper toward the tip on both sides to about half the original thickness, this helps avoid gaps to the nose cone when glued at the tip.
Lay the model along a table edge and glue the curved chine portion only to the nose cone, keeping it straight and flat. Make sure the rear butts against the chines on the body tube. Repeat on the other side and put a fillet on both. You may need to trim/sand it to fit against the wing before gluing. Be careful and don’t get glue to far to the rear and glue the nose cone into the tube or the chine to the body tube, just the nose cone!
Lightly sand the edges of the nose chines to align with the rear chine and blend it into the nose cone at the front.
I put a good fillet of CA on both sides after removing the nose cone, and added a little more in several coats at the tip top and bottom to fill in any gaps. Make sure the CA is cured before continuing.
Shape the cockpit referring to the photos as a guide. The bottom will need to be sanded at an angle toward the rear then wrap sandpaper around the front of the nose cone/body tube and sand the bottom of the cockpit so that it will conform to the cone. Glue in place on the nose cone with the rear even with the end of the body tube.
Glue the two pushrods/control horns in the bottom of the wing in each control surface in the pre-punched holes using CA+. Apply CA+ to the top of the control surface on the prongs from the control horns to capture them in place. Set with accelerator. Note in the picture how the control horns face, the flat part of the control horns faces forward so that the holes that the pushrod go in are even with the hinge line and the pushrods are closest to the body tube.
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 use this arm and trim off one end. Zero out any trim settings on the transmitter.
Flip the model upside down.
Connect each servo to the pushrod.
Mark where the servo will sit against the body tube and mark and cut a pocket to fit, make sure the servo will fit into the pocket and the control surface will stay level when the servo is installed. Trim as needed. I removed the servo mounting flanges as they are not needed.
Attach a servo extension to each servo long enough so that it will go the full length of the body tube and out the front to allow you to connect it to the receiver. Route the servo wire forward through the pocket and reconnect to the receiver and power up the system.
With the radio still on, put a moderate amount of glue on the servo, being careful not to get any near the output shaft, and set it in in the pocket keeping the control surface centered and against the wing. Don’t inset the servo more than half way so that the other servo can also inset on the other side. Repeat on the other side. Make sure the glue is set before continuing.
Mask off the rail buttons.
Paint the model using ONLY testors or model master enamel spray paint or Krylon short cuts small rattle can enamel spray paint. This is the only paint I recommend. I’ve used testors and model master flat black. Mask off the rail buttons. Do not spray too close to the model. Use many light coats and do not spray heavy. I apply a coat to all the edges of the foam first since it tends to soak into the sanded exposed edges and look lighter, then apply light coats till the model is covered. Paint adds weight, use just enough to get a nice even finish.
If you use the stickershock decals, after applying them use a hot hair dryer to soften them and press down with your finger to make them conform to the foam/paint better. I did not use the transfer paper to put the cockpit decals on, I removed the transfer paper and used an exacto to peel them off and apply one at a time.
For the red strips you will need to cut them to length and apply each by hand. Be careful not to try to pull them off and reposition as they will pull the paint off of the wing, just be careful and only press down once they are in the right spot. See the photo below for a guide. The strips need to be cut as follows: 1.25″, 1.25″, 9 7/8″, 2″, 1.75″, 1.5″ . You will apply the 1.25″ strip at the front of the wing about where the chine starts to curve toward the nacelle, it goes up the body tube about 1/4″ and angles outward, then second 1.25″ strip parallel with the leading edge of the wing. The long strip starts at the end of the second 1.25″ strip, angles and curves inward a bit then straight back toward the body tube and stops about 1/4″ away from the tube at the end. You can press down and pull it slightly to get it to curve as you apply. The 2″ strip starts at the end of the long strip and goes parallel with the hinge tape just in front of the tape, don’t apply to the hinge tape, then the 1.75″ strip goes next to the inboard portion of the nacelle touching the 2″ strip. The 1.5″ strip starts just ahead of the hinge tape goes parallel to the outboard of the nacelle. Repeat for the other side. For the small rectangle of red to the rear of the cockpit you can use 1″ long and 1/2″ long strips to make that, I put a half inch strip over the joint where the two body tubes join and then put the two 1″ strips going forward and the other 1/2″ strip to make a box.
Attach the receiver and battery into the nose cone using the supplied velcro. I slid the receiver into the cone and then used velcro to hold the battery behind the receiver which holds both in place.
Install your loaded motor.
Support the model at the balance point indicated for boost. Add weight as required to balance into the nose. Hold it in place with the foam safe CA. Do not try to fly the model too nose or tail heavy. Remember, a nose heavy model flies poorly, a tail heavy model flies once. I added a little at a time and re-checked often till it was just balancing slightly nose down. Do not just use all the shot included or you will be nose heavy most likely.
Set up your throws and trims: The model uses approx 3/8″-1/2″ up and down elevator throw and 1/4″ to 3/8″ left and right aileron throw. It is quite roll sensitive on boost so you may tone this down as needed. For boost I used zero control trim for the first flight but found I needed about 5-6 clicks of down trim for straight boost. For glide I’m using about 3/16 of up trim or a slight bit more. I put this trim onto my flap switch so that I can go from boost to glide trim with the flip of a switch, you can also use a flight mode to do the same function. Make sure when you launch you are in boost trim or it will be a very short flight.

Flying: Be ready on the first few flights to keep the model straight till you have the trims set perfectly for boost and glide. Try to do initial flights in dead calm conditions. You need to be ready to react quickly to keep it boosting straight up or slightly away from you. Keep the wings level. Push the model over level as the motor burns out and it slows down. Then click in the up trim. Avoid drastic bank angles which cause you to lose altitude and make it easy to lose orientation. Gently fly around, and set up for landing into the wind when about 100′ high. The model will rock the wings if you start to get too slow, if this happens push forward on the stick slightly. The decent rate is very predictable, keep some speed up so you don’t stall, and keep the wings level as it decends and gently flare just before touchdown.

: Kit parts

: Wing joint glued.

: Spar glued in place.

: Wing joint and spar taped with blenderm tape.

: Draw an alignment line for each nacelle, line goes from the front inboard edge of where the triangular intake shape hits the front of the wing to the inboard wing trailing edge cutout.