Aerodynamic Flutter
The wings of aircraft swaying as if dancing to the music of the winds is a fascinating spectacle indeed. This phenomenon in the engineering vernacular is known as Aerodynamic Flutter.
Flutter is an unstable oscillation which can lead to destruction. Flutter can occur on fixed surfaces, such as the wing or the stabilizer, as well as on control surfaces such as the aileron or the elevator for instance.
Wings are sort of like springs
Wings are very flexible. Well if the wings were rigid ( as you can guess ), it would snap at the slightest turbulent load; But since gusts are just a part and parcel of the flying experience, it is impertinent to address them.
If flutter does not occur:
The vertical vibrations of the wings are damped i.e the amplitude of the vibrations die out and as a result do not necessarily do much harm.
If flutter occurs :
However if flutter occurs, the periodic vibration of the gust has a frequency similar to the natural structural frequency of the wing, the vibrations are amplified.
The amplification of these vibrations eventually leads to its destruction.
Prolonged oscillation and Fatigue
The number of oscillations and the amplitude with which you make the oscillation has a huge impact of the life of any object.
In fact there is something known as the Fatigue-curve that denotes the behavior.
Have a great day!
Sources and more:
Flutter at a glance - NASA
Airbus A380 Flutter test
The tale of the โGallopin Gertieโ - Tacoma Narrows ( detailed account )
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Maybe @missaerospaceblog can dedicate a post on the impact of flutter on Rockets and spaceflight ?
