What are longerons primarily used for in fuselage design?

Longerons are critical components in fuselage design, primarily serving to provide structural support alongside the skin of the aircraft. They run longitudinally along the fuselage, helping to maintain the overall shape and integrity of the structure. This support is essential for distributing loads and stresses that occur during flight, which ensures the fuselage can withstand various forces, such as aerodynamic pressure and load variations during maneuvers.

In addition to offering structural reinforcement, longerons also play a role in defining the overall design and architectural integrity of the fuselage. This is crucial not only for safety and durability but also for facilitating the attachment of other structural elements and components, such as frames and bulkheads. While aesthetic considerations and weight reduction are significant in design processes, the primary function of longerons is their role in providing essential structural support.