the human body can only produce 0.4 horse power which is nowhere near enough power to flap the wings of early unsuccessful human powered aircraft which require about 10+ horsepower. until people started using motors nothing worked.
Ornithopter
by running and jumping off the ground, also by flapping their wings -Although SOME birds (like the Albatross) have a hard time flapping, THEY HAVE TO WAIT for a strong breeze. Airplanes' wings are thicker at the front of the wing than at the back of the wing. This is in imitation of birds' wings.
It is flapping wings.
ILeonardo da Vinci sketched numerous flapping aircraft but flapping wings is not energy efficient Each flap of the wings requires yet another burst of energy and it all adds up. Hummingbirds have the highest energy expenditure of any warm-blooded animal -- 10 times that of a human. They're always on the verge of starvation and have to consume colossal amounts of nectar to keep up.
It is flapping wings.
by flapping its wings
By flapping them?
Dangling participles make for very odd, awkward, and often humorous sentences.Wrong: Flapping its wings wildly, the dog was fascinated by the bat stuck in the fire place.A dog has no wings to flap, but in this sentence " Flapping its wings wildly" is meant to refer the dog.You need to get " Flapping its wings wildly," to refer to the bat.Correct: The dog was fascinated by the bat that was stuck in the fire place and flapping its wings wildly.Correct: The dog was fascinated by the bat stuck in the fire place, flapping its wings wildly.
All airplanes have at least two wings.
by flapping their wings
by flapping their wings
By flapping them?