Dave Guzman, a friend and professional comrade (electrical engineer, owner of RfTek) of mine from the Raleigh, North Carolina area, built and flew model airplanes as a boy in Columbia. A picture of his Fokker DR-1 Triplane, one he build many moons ago, is shown to the left. The J-3 Cub to the right is one he asked me to build and test-fly for him since it had been so long since he had flown anything. I gladly took on the task.

He bought a Hi-Tec 3-channel radio for it. As with the GWS Tiger Moth that I had bought for myself, the GWS J-3 Cub needed some structural improvements to make it more durable. I cannot recall exactly what changes I made, but one was definitely to NOT use the crappy glue that is provided in the kit. Reinforcing of the wing strut attachment points was needed, and learning from the GWS Tiger Moth, about 5 degrees of down thrust was built into the motor mount. The Tiger Moth had a severe tendency to climb in a when the power was advanced past about half throttle. It turned out being a good decision, because even with the much down thrust, the GWS J-3 Cub still liked to climb at high throttle settings.

I took the J-3 Cub along to a small party that Dave and his wife threw at their house, and after eating, we all walked across the street to for the maiden flight. The radio was range checked, a quick preflight on the structure, and it was tossed into the air. Thankfully, the crowd was treated to a perfectly trimmed and flying airplane. After a few trips around the field I put it into a dive and pulled up into a really bad loop, but everyone was happy to see it. It flew around doing low passes until the battery ran out of power and made a nice landing in the grass. It was getting really dark by then, but we stuck in the other battery and heaved it into the air again. Dave flew it for a short time, but it was difficult to maintain visual orientation with the low light, so he handed the transmitter back to be and I flew until the battery crapped out.

Here is my non-scale covering of the Great Planes J-3 Cub 20. It was originally covered in an L-4 Grasshopper scheme, but my lousy eyesight made it hard to tell what was happening due to the lack of color contrast, so I re-covered it as shown. While at it, I turned the O.S. 25 LA engine upright to eliminate the need to turn the darn thing over to start it (flooded otherwise). I also fixed the ailerons in place to make it a 3-channel setup - the ailerons were not very effective, so I figured why bother. Mounting the engine far enough out on the mount to reach front resulted in a lot of springiness, so I moved the engine back close to the firewall and added a prop shaft extender from Fox.

The current setup is for a Futaba radio with three S3004 standard servos. There is plenty of room for any radio. A 6-oz. fuel tank is installed and pressurized by the muffler. I'm going to convert it to electric power.