Study on the flight of birds. Designed by using the principle of kite glider from the paper can sift go far to 60 feet. Later the full and succeed in gliding from the hills, without being forced in 1999. 1809 has published works about the aviation. Which describes the problems of flight at the surface the weight limit. By going against the air resistance.
การแปล กรุณารอสักครู่..