About BAE Systems Intelligence & Security BAE Systems, Inc. is the U.S. subsidiary of BAE Systems plc, an international defense, aerospace and security company which delivers a full range of products and services for air, land and naval forces, as well as advanced electronics, security, information technology solutions and customer support services. Flight Systems plays a critical role within the Sentinel program, focusing on evaluating the design of solid rocket motors, guidance, navigation and control equipment, post-boost liquid propulsion systems, reentry vehicles, and support equipment.