Why Do Airplane Wings Bend So Much?

Why do airplane wings bend so much? Each wing carries half the airplane, pushed up by lift, so it bends like a fishing rod with a big catch. That flexibility is deliberate: when turbulence hits, the wing gives a little and soaks up the jolt like a spring. How strong are they? In a 1995 test, Boeing bent a 777's wings until they snapped — at 154 percent of the worst load the airplane is ever expected to see (the rules require 150 percent). In normal cruise at 1 g, the wings use only about a quarter of that breaking strength.
Note: wing deflections in the animation are exaggerated for readability; the test rig is simplified.

Sources:
– Boeing Images, 777 wing load test:
– CBS News, wing load tests (777 / 787):
– 14 CFR 25.303 (factor of safety):
– 14 CFR 25.337 (limit maneuvering load factor):
– Mental Floss, why wings wobble in turbulence: