T H E main transverse frames of many aircraft structures are extremely redundant. In the hulls of rigid airships and flying boats and in the fuselages of airplanes the tendency of design is towards deep, continuous ring frames, which are in themselves structurally redundant, and may present quite difficult problems in stress analysis. The problem becomes much more complicated when transverse bracing members are added to the frame. A method of stress analysis of such structures is presented in this paper. The analysis of a main transverse frame of a rigid airship, constructed as a deep ring with tight radial wires, is given as an illustrative example.