The Graupner Starjet

Specifications: Wingspan: 47 inches; Wing Area: ~632 sq. in.; Wing Loading: ~ 11.4 oz./sq. ft.; Weight: 50 oz.; Recommended power: 2x Speed 400 6V; Servos uesd: 2x sub-micro HS-55 servos; Manufacturer: Graupner; Available from: Hobby Lobby

Kit Contents

The StarJet comes in an absolutely huge box. I almost couldn't fit it in my car to get it home. Since it is foam, there is relatively little packaging or padding in the box. I've been through two StarJets now (radio problems with the first), and both have had only a few minor blemishes, but nothing flight threatening.

Assembly

First and foremost, you will need a supply of sharp hobby knife blades. You won't have to replace the blade after every cut, but don't be bashful about replacing a dull one. Your cuts will be cleaner and your building experience will be more enjoyable.

The instructions begin with cutting the aileron end slots. I opted to de-bur the plane first, which is listed as step two in the instructions. This process entails carefully cutting away the excess material from the foam molding process. Use a sharp blade and take your time. It is actually kind of fun.

Once the prep work is done, it's on to the hardware installation. That is all that is really left to do to finish building this plane. I began with the motor mounts. The design calls for the two speed 400 motors to be glued directly to the foam, one in each motor channel. I was planning to try out a few different motor setups, so this technique would not work for me. In addition, a mount would also aid in motor replacement in the event of bent motor shaft. The result was a simple compact removable motor mount detailed on the left.

The mounts are constructed so that the motors rest in the original mounting locations at the factory specified angles. The mounts are glued in place with 5-minute epoxy. You don't need to build this motor mount or use it for your setup, unless you plan to upgrade to hotter motors at a later date. Personally, I've found the Hobby Lobby recommended setup (two 6V speed 400 motors on eight 1900mah cells) to be a great performer.

The battery (8cell -1900mah) mounts to the battery tray with Velcro. It can be moved forward or aft for balance. The receiver is also mounted with Velcro. Everything fits nicely under the removable canopy.

The next step is to glue the two vertical fins in place with 5-minute epoxy. To prepare the main wing for installation of the fins, cut 60mm tall blocks and place them under each wingtip. Next, weigh down the center portion of the fuselage. This gives the StarJet a small amount of dihedral for stability. Once the blocks and weights are in place, carefully glue each fin in place. Make sure you mix plenty of epoxy so you don't run out during installation. Work on one fin at a time and leave the plane in its blocked position until the glue cures.

With the exception of a few decals and a little work with the control throws, the StarJet is ready to fly.

Flying

I asked Ken Johnson to hand launch the plane while I was ready at the controls. I spooled up both motors and Ken gave the StarJet a good firm throw. Starting out at about head high, the plane dropped a foot or so as it got on step.

Conclusion

Reprinted courtesy of the Ezone magazine.