Abstract: The invention relates to systems and methods for manufacturing composite parts for aircraft. In one innovative aspect, a system and method for adjusting a location of a center of gravity of an aircraft relative to a center of lift of a wing of the aircraft is disclosed, wherein a modular spar tunnel mold is provided and configured to be detachably fixed at a plurality of selected locations within a main mold for a fuselage portion of the aircraft. In another innovative aspect, a movable detail or mold is used for manufacturing complex composite parts for an aircraft. In yet another innovative aspect, a movable detail is used to fabricate a common feature for a plurality of different parts for one or more aircraft or a family of aircraft of similar design.

Abstract: A hybrid composite-metal energy absorbing seat is described. According to one embodiment, an aircraft seat includes a seat base assembly and a seat back assembly. The seat base assembly includes multiple rigid metal seat base side frame elements joined by a lower seat pan, an energy absorbing element placed on the lower seat pan to deform and absorb downward energy in a crash, and a contoured seat pan whose sides extend past the seat base side frame elements and deform to absorb downward energy in a crash. The seat back assembly is attached to the seat base assembly and includes multiple rigid metal seat back side frame elements joined by a contoured composite seat back. The rigid metal seat back side frame elements absorb forward crash load energy by permanently deforming during a severe forward crash load. The contoured composite seat back provides design/aesthetic flexibility.