Norel: GlassAir 400

Model Airplane News, Sep 2001 by Trachten, Craig

A high-quality glider for glow or electric power

Norvel's GlassAir 400 is a great new entry in the fast-growing world of park flyers. It is a high-quality, powered sailplane that is a perfect size for the local football field. My wife jogs on the track around the field while I'm on the 50-yard line exercising my thumbs. A really nice feature of the GlassAir 400 is that it can be built for either glow or electric power; the instructions for both are provided with the model, so you don't have to figure out conversions. As its name suggests, this model's fuselage is fiberglass, and it comes with semi-transparent metallic covering on the wing and tail surfaces. '[he kit also includes hardware for both power options. I had been wanting to try Norvel's BigMig .061 anyway, so that's the powerplant I chose.

ASSEMBLY

Unlike any other ARF I have built, construction on the GlassAir 400 starts with the canopy rather than the wing. Cut out the canopy along the scribed lines (a good pair of Lexan scissors will do the trick). Drill a 5/32-inch hole in the rear of the cockpit and epoxy in the short dowel. Bevel the half-round canopy former and place it over the dowel, but do not glue it! This former gets glued to the canopy. Put the canopy in place and check the fit; trim it as needed. Then, tack-glue the former to the canopy with a drop or two of thick CA. Drill a 5/64-inch pilot hole in the front of the canopy, and secure it with a 3/8-inch screw.

Now, assemble the wing! Test-fit the metal dihedral brace and alignment dowel. Snug is good, but don't tighten them too much; you want to be able to separate the wing halves with little effort but without any slop in the joint. Epoxy the brace and dowel into one wing half only, and make sure that the dihedral brace is angled upward. Remove the covering from over the predrilled wing-bolt holes. Place the wing on the fuselage, and use the holes in the wing as your guide for drilling the fuselage. Drill two 9/64-inch holes in the fuselage's mounting block and tap the holes with the supplied metal self-tapping screws. Then secure the wing to the fuselage with the nylon bolts. Mark the wing where it meets the fuselage, then remove it; these marks will guide your installation of the wing-alignment blocks. These blocks will prevent the rear of the wing from shifting or separating during flight.

It can be a little tricky to attach the horizontal and vertical stabilizers. Unlike most ARFs, the GlassAir has no slots in the fuselage to slide the stabilizers into; they are surface mounted. Remove the covering from the horizontal stabilizer where it is attached to the fuselage, and make sure the open side of the hinge is down. Attach the wing to the fuselage and place both on a flat surface. Support the wing so that each tip is the same distance off the table. The instructions call for 5-minute epoxy, but I used 30-minute to secure the horizontal stabilizer to the fuselage. It gave me more time to work and affords a stronger bond. Make sure that the stabilizer fully contacts the fuselage and is parallel to your work surface. Let the epoxy cure completely before you continue.

The vertical stabilizer is a bit more difficult to install. Mark a line that is 90 degrees from the horizontal stabilizer and in the center of the fuselage. Because there is no slot or groove to hold the stabilizer in place, I was concerned that it might shift while the epoxy cured. On each side of the fuselage, I used a combination square on top of a block to hold the vertical and horizontal stabilizers perpendicular to each other. A small piece of masking tape placed across the front of the vertical stabilizer and the two squares ensured perfect alignment.

When everything has cured, attach the control horns to the elevator and rudder as you would with any model aircraft. Mount the rudder horn on the left side and the elevator horn on the bottom center of the elevator.

I deviated from the instructions when I installed my servos. Since I chose to go glow, I needed three servos, but I did not use the recommended servo rails or servo tape. I secured my servos using Bob Smith's IC2000 tire glue. It is a rubbery black CA used to glue tires onto the rims of RC cars. I have used it before for mounting servos, especially in foam wings and fuses. I used FMA S200 servos for the rudder and elevator and an S100 for the throttle. I mounted the throttle on the left side with the front edge of the forward compartment bisecting the servo. I mounted my 600mAh receiver battery opposite the throttle servo and placed FMA's Quantum 6 sub-micro receiver between them. With the BigMig on the nose, this configuration gave me perfect balance. After you've installed the servos, measure, make and install the pushrods.

Following the directions for mounting a glow mount, epoxy the plywood nose ring to the inside of the fuselage. This is what the engine mount will be secured to. Attach the engine mount with four screws, and drill a hole for the throttle pushrod. I tucked a 1-ounce Sullivan fuel tank under the canopy, 2 inches behind the firewall.