6. Flying
Before flying, bend the tail slightly upward. Start off with some low-power tests to get the model adjusted correctly. This should be done indoors or in windless conditions. Wind the motor 40 times. Launch the model with a gentle forward push (don’t throw it) and observe the flight path. Try winding the crank in both directions to see which works best.

In the low-power test, this ornithopter should slowly descend while flapping its wings. If it makes a nose-dive, bend the tail up slightly. If it stalls (tries to go up, but then drops sharply), bend the tail down a bit.

Twisting the outer portion of the crank with pliers controls the flight direction, left or right. Adjusting the crank changes the flapping angle, and therefore thrust, of the right wing. For best results, try to make the model fly as straight as possible.

Once the model is flying fairly well, you can wind it all the way up to 130 turns. That should give it more than enough power for climbing flight. Further adjustments may be required after you see how the model behaves with more power.

Ornithopters are fascinating to watch, but experimenting with them is even more captivating.

These excellent designs for making your own ornithopter were produced by Nathan Chronister. To learn more about ornithopters and get some plans for further flying models, take a look at his site at www.ornithopter.org.

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