Scratch X-Wing Fighter Original Design / Scratch Built

Scratch - X-Wing Fighter {Scratch}

Contributed by Eric Maher

Manufacturer: Scratch
(by Eric Maher - 11/18/05) XWing

I started work on the X-Wing shortly after getting level 1 certification. Construction was based on a set of plans I found on a Japanese website for a paper X-Wing model. From these plans, I was able to create templates for the X-Wing's fuselage bulkheads, wings, cockpit and nosecone. Construction began with the purchase of a 38mm motor tube, a sheet of 1/4" aircraft plywood and several 1/4" dowels. I cut the fuselage bulkheads from the plywood, notched them at the corners to accommodate the dowels, then joined them together. Anyone who has built model airplanes will be familiar with this type of construction. A 2 1/2' long section of 2.6" body tube was placed inside the forward end of fuselage to contain the parachute and to allow easy attachment of the nose cone. The fuselage was then covered with cardboard. After much filling and sanding, two wraps of 6 oz fiberglass were applied to the fuselage. Holes were cut in the bottom of the fuselage to accommodate the 1/2" copper pipe that would serve as the launch lug.

In progressWith work finished on the fuselage, I began on the wings. The wings are constructed of a basswood skeleton covered with a glassed balsa skin. The engine fairings are build from cardboard reinforced at the corners with basswood. Three different body tube sizes were used in the construction of the wings. The large motor tubes are 4" cardboard tubing, the rear "afterburners" are 2.6" tubing and the lasers on the wingtips are made from 54mm motor tubing. All tubing was purchased from LOC Precision. When the wings were complete, mounting holes were cut in the fuselage. Wing are mounted through-the-wall; butted up to the motor tube.

NOse ConeThe nose cone and cockpit are built from the same cardboard that was used to cover the fuselage. Again, templates were created from the paper model plans. A 2.6" coupler was epoxied inside the nosecone to allow attachment to the fuselage. 2 lbs of BB's and epoxy were added to the nosecone for stability.

The detailing on the rear of the model was made with wood bits from Michael's arts and crafts. There are pieces of wooden flower pots, bowls, milk cans, etc. R2-D2 is from an old Estes mini-engine powered kit.

During final assembly, the wings were glued in place and acrylic panels were installed between the top and bottom wings for increased strength and to improve stability in flight. All gaps were filled with an epoxy paste called PC-11. Many hours of sanding were required to get the model ready for paint. The paints used were 4 cans of Testors camouflage gray (if anyone knows of a lower cost alternative, let me know!), Testors Yellow and Krylon Red. A mask was created to spray the "red five" pattern on the wings.

With construction nearly complete, I began to think about recovery. The finished model weighs in at about 13lb with motor installed. It was going to be difficult to get enough chute into this thing. The best I could do was two 48" chutes on the rocket, and a separate 36" chute on the nose.

FlightThe rocket flew at NYPower 11 on an Aerotech I-284 with 6 second delay. I had thought about trying to do a level 2 cert with the model, but I was not at all confident that the model would be recovered without damage. Besides, I really want to get into altimeters and dual deployment for my eventual level 2 attempt. Breezy conditions made if difficult to orient the rocket edgewise to the wind. A brace was improvised using a piece of body tube that was found near the launch pad and some wire from used igniters. Takeoff was slow, and the flight path was a gentle arc onto the rocket's back. The flight was slightly marred by the premature separation of the 2lb nosecone which proceeded to snag on one of the wings. Maximum altitude was around 500' The fight was a real nail biter with the twin parachutes deploying about 100' off the ground. As expected, the chutes were not sufficent to prevent damage to the rocket. Two of the "afterburners" were damaged, one heavily. A split also occurred along the front of the fuselage, this may have been caused by the premature separation, or the plus-size ejection charge that was used to ensure deployment. The model is repairable.

The rocket was a real crowd pleaser. People seem to like the more unconventional models. To my knowledge it was the only rocket at NYPower that got a cheer when the chutes deployed.

This was my first scratch built high power model, and it was a great experience. The excitement is much higher when you are flying a model you built from scratch. I highly recommend giving it a try.

Special thanks to Bobby Buchalski from Hanger 11 for assistance and advice in prepping the model for flight and to Chuck Rudy from Voodoo Digital Productions for assistance at the launch pad.

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