THE trend of large, fast airplane designs is toward greater flexibility and more rapid application of landing and flight loads.
With this combination of conditions, the inertia forces associated with the elastic distortions of the structure can not be ignored. In turn, the elastic forces are changed so that a rigid-body load analysis becomes inadequate and dynamic load analysis is necessary and of significant advantage in promoting efficient structural design.
If the history of the exciting forces is known, a dynamic analysis is feasible by the methods described here. These methods require careful application to account successfully for the complex distortions of the airplane structure. The responses are calculated by a classical linearized solution; these are then employed in the determination of loads.
An example of the dynamic bending moments in an airplane hull during a water landing and another example of the dynamic shears in an airplane wing traversing a gust are given.