The monocoque (single shell) fuselage relies largely on the strength of the skin or covering to carry the primary stresses. The design may be divided into three classes: (1) Monocoque, (2) semi· monocoque, or (3) reinforced shell. The true monocoque construction (figure 1-5) uses formers, frame assemblies, and bulkheads to give shape to the fuselage, but the skin carries the primary stresses. Since no bracing members are present, the skin must be strong enough to keep the fuselage rigid. Thus, the biggest problem involved in monocoque col18truction is maintaining enough strength while keeping the weight within allowable limits.
To overcome the strength/weight problem of monocoque construction, a modification called semimonocoque construction (figure 1-6) was developed. In addition to formers, frame assemblies, and bulkheads, the semimonocoque construction has the skin reinforced by longitudinal membel8. The reinforced shell has the skin reinforced by a complete framework of structural members. Different portions of the same fuselage may belong to any one of the three classes, but most aircraft are considered to be of semimonocoque type col18truction.
In addition to formers, frame assemblies, and bulkheads, the semimonocoque construction has the skin reinforced by longitudinal membel8. The reinforced shell has the skin reinforced by a complete framework of structural members. Different portions of the same fuselage may belong to any one of the three classes, but most aircraft are considered to be of semimonocoque type col18truction.
