Birds inspired our first attempts to fly, but our progress was limited until we learned that we could not fly like them. Thanks to their light weight, great strength, and complex biological design, birds and other flying creatures can use their wings to create both lift and thrust, as well as to maintain control. But we had to invent a different approach. We separated the functions of lift and thrust, using wings to produce one and engines to produce the other.

Though we still cannot fly like birds, we can now fly with them.

Courtesy of NASA

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(Rev. 10/22/96)