"I Want to Fly Like an Eagle"

Or a gull.



They still had to add in a small downward-pointing vertical stabilizer in order to make the model bird maintain stable flight. So they are not quite there.

Still, I wonder about how much power is consumed by flapping the wings compared to a fixed wing and a prop, especially in scaling. There are quite a bit of timing and control issues in working a flapping wing. If it had been possible in an evolutionary sense to develop balanced high-speed rotational structures, birds might have also had propellers.*
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*Maybe they would have had to evolve runways, as well.