Which design feature allows an aircraft to maintain its structural integrity while being lightweight?

The design feature that enables an aircraft to maintain its structural integrity while keeping it lightweight is the concept of stressed skin. In this design, the skin of the aircraft not only serves as a covering but also acts as a structural component. This approach distributes the loads that the aircraft experiences in flight, allowing the skin to carry both shear and bending loads. By integrating the skin into the overall structural framework, engineers can reduce the need for additional internal support structures, which contributes to weight savings without compromising strength and rigidity.

Stressed skin construction effectively allows the airplane to utilize the outer skin as a critical part of the load-bearing structure, which is especially important in aerospace applications because weight reduction is essential for improved performance, fuel efficiency, and payload capacity. This method contrasts with designs that may rely more heavily on an internal framework, which can add unnecessary weight.