Scratch - XR-71 Green Burd {Scratch} Original Design / Scratch Built

Contributed by Dick Stafford

Manufacturer: Scratch
(Contributed - by Dick Stafford - 07/18/02)

Brief:
This is a scratch built jet fighter that is roughly patterned after the SR-71 Blackbird. As you can see, I wasn’t terribly creative in the naming department.

Construction:
This rocket was built around the mid 80’s after I became a BAR. The main body tube is BT-50 and the side tubes are BT-20. The main nose cone is constructed from a balsa bulkhead and a plastic missile from one of my son’s toys. Small pieces of scrap balsa keep it from sliding into the body tube. The nose cones on the pods are balsa and there is a small piece of BT-5 mounted in the rear of each pod. It has an 18mm motor mount and an old rubber band shock cord. The main wings are 3/8” balsa. The long forward sections and the stabilizers mounted on the pods are 1” balsa strips that taper from 9/16” to 3/16”. Finally, the cockpit was carved from a section of ½-oval balsa (kind of like oblong ½-round molding).

I started to paint the top of the rocket in Day-Glo green and the bottom solid gray. I mixed the Day-Glo green with some regular green (both Testor’s) so I could transition from a darker green on the body to a lighter green on the fins. However, I ran out of Day-Glo paint and, rather than replace it, the body ahead of the side fins is camo green. You can see the additional white and Day-Glo orange trim. The protruding BT-5 tubes on the pods are painted gold.

Flight:
This rocket has flown only once on a C6 motor (can’t remember the delay). After performing a swing-test, I added a couple of lead pellets as nose weight. Still, it whipped the rod as it boosted and headed off at a low angle. Recovery was successful, but if I fly it again I need to either add more nose weight or maybe use my BlackSky rail.

Summary:
This design is not unique, but is much more interesting than a 3/4FNC rocket. The tapered slats worked out nicely.

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