Abstract: The present invention pertains to a method for producing a frame for a working hull, specifically an aircraft fuselage wherein at least a part of the frame is in the form of a monolithic structure. The method includes the steps of draping unidirectional and multidirectional fabrics impregnated with resin on a form, placing inflatable bladders between the form and a counter form, closing a mold on the form, inflatable bladders and a counter-form, inflating the bladders to compress the fabrics and heat-set the resin impregnating the fabrics. Thereafter, the monolithic structure is removed from the mold.

Abstract: In order to reinforce a working hull, such as the fuselage of an aircraft and in particular that of a helicopter, a frame (C) is embodied made of a composite material in the form of a monolithic monobloc structure. This structure is constituted by a profile whose internal flange (16) and the external half-flanges (18) principally comprise unidirectional fibers which extend over its entire length. As a variant, the lower section of the frame is embodied separately in the form of a panel bordered over its entire periphery by lateral half-flanges which also principally comprise unidirectional fibers. After assembling the two sections of the frame, the half-flanges are then opposite each other in the elongation.