Spirit AeroSystems Holdings, Inc. engages in the design, engineering, manufacture, and marketing of commercial aerostructures worldwide. It operates through three segments: Commercial, Defense & Space, and Aftermarket. The Commercial segment offers forward, mid, and rear fuselage sections and systems, nacelles, struts/pylons, horizontal and vertical stabilizers, flaps and slats flight control surfaces, wing structures, and fully functional and tested wing systems. This segment primarily serves commercial and business/regional jet programs. The Defense & Space segment engages in the fabrication, bonding, assembly, testing, tooling, processing, engineering analysis, and training on fuselage, strut, nacelle, and wing aerostructures; provision of missiles and hypersonics solutions, such as solid rocket motor throats, nozzles, re-entry vehicle thermal protections systems; forward cockpit and cabin, and fuselage work on rotorcraft aerostructures; and classified programs. This segment primarily serves U.S. Government defense programs. The Aftermarket segment provides maintenance, repair, and overhaul (MRO) services; fuselage, strut, nacelle, and wing aerostructures spare parts; repair services for radome, flight control surfaces, and nacelles; rotable assets trading and leasing; and engineering services. This segment primarily serves both Commercial and defense and space programs. The company was formerly known as Mid-Western Aircraft Systems Holdings, Inc. Spirit AeroSystems Holdings, Inc. was founded in 1927 and is headquartered in Wichita, Kansas.