Denny Dart II Flight Tests

I woke up late this morning. I’m used to working until 2-4 AM, but got up at 7 AM yesterday to ROG a Squirrel. Couldn’t do it a second time. So I got off to a late start, there was already some wind, but light. I was in such a hurry that I forgot to bring the pole and lube. The lube from yesterday was dry. I rubbed a drop of water into it from the faucet.

200 turns produced a nice high flight turning to the right, but the climb was fitful rather than smooth and steady. The glide was not good because the prop backwound the motor 25 turns and stopped rotating. A longer motor would allow freewheeling and a longer glide.

250 turns banked steeply to the right and the sideslip prevented climb. 300 turns was worse.

A motor that produced the torque of the 200 turns would fly this plane fairly well, but the climb would be erratic. Wing twist would fix the bank, but at a cost of energy. Better to eliminate the cause of the problem.

The right turn is caused by the prop pointing up into the incoming air. The prop must be coaxial with the wind direction to avoid disturbing forces.

It was difficult to make videos because the sun was already high in the sky and I could not visually follow the plane. Also,it flies pretty fast and erraticly. I did get a couple illustrative videos, though. The attached is the first one with 200 turns.

This configuration has the potential for much longer flights with careful adjusting.

I will build another with a plastic prop bearing.

Gary Hinze

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