Leidos Defense is seeking a highly skilled, visionary Principal Systems Engineer / Technical Program Manager role to join our multi-disciplinary engineering organization. This role, you will encompass aspects of both senior technical leadership and program management by helping customers define complex problem spaces, drive system architecture in multi-contractor environments, define/help refine programmatic concerns and guide high-performance platforms from concept through design-for-manufacturability and production for critical Department of War (DoW) initiatives. As a Principal contributor, you will act as a primary technical liaison with government stakeholders and contractor collaborators, translating complex customer concepts into executable architectures. You will provide strategic technical direction across multi-functional Integrated Product Teams (IPTs), identify communication bottlenecks, manage high-level engineering complexities, and guide teams through the entire lifecycle from theoretical development to the production floor. Primary Responsibilities. - Collaborate with government customers and stakeholders to define complex problem spaces, operational needs, and mission requirements for advanced high-speed atmospheric weapon systems and associated high-performance platforms operating under extreme thermal, aerodynamic, and environmental conditions. - Lead system architecture definition and integration across multi-contractor collaborative environments, establishing clear interfaces, conducting trade studies, and driving technical consensus among government, prime, and subcontractor teams using systems engineering best practices and MBSE methods. - Oversee the full program lifecycle from theoretical concepts, requirements negotiation, and early analysis through design maturation, verification, design-for-manufacturability (DFM) implementation, production transition, and factory floor execution while maintaining cost, schedule, and technical performance. - Identify and resolve communication bottlenecks, interface gaps, and organizational misalignments between government personnel, contractors, and functional teams to ensure efficient decision-making, reduce risk, and maintain program momentum. - Direct multi-disciplinary Integrated Product Teams (IPTs) and serve as primary technical liaison with government customers; host regular technical interchange meetings, negotiate requirements, ensure traceability, and drive risk/opportunity management to maintain alignment across all partners. - Partner with systems engineering and Control Account Managers (CAMs) to establish program baselines, develop work breakdown structures, provide rigorous EVM inputs, support competitive proposals, and implement change management processes that prevent scope creep while enabling smooth technology transition from development to full-rate manufacturing. Basic Qualifications. - Active Secret Clearance, with the ability to obtain a Top Secret clearance - Bachelor’s degree in ABET accredited Engineering discipline with a mix of 12+ years of systems engineering and/or technical program management experience, or a Master’s degree and 10+. - Proven background helping customers define complex problem spaces, developing baselines, and managing cost, schedule and performance for high-performance defense platforms operating in extreme thermal, aerodynamic, and environmental conditions - Comprehensive working knowledge of systems engineering best practices, Risk and Opportunity Management, Earned Value Management, Change management, and requirements negotiation with customers to ensure traceability through all levels - Demonstrated experience leading, organizing and collaborating with various Subject Matter Experts, Functional members and managers (all non-direct reports) while working closely with the customer and government personnel to identify project risks/opportunities - U.S. Citizenship is strictly required - Ability to travel 10–20% Preferred Qualifications. - Familiarity with Model-Based Systems Engineering (MBSE) methodologies, SysML concepts, or requirements tools such as IBM DOORS. - Prior experience developing competitive proposals that led to major program awards ($4M+) and executing programs under budget with EVMS metrics. - Hands-on experience designing experiments for failure analysis, design verification, design trade studies, and root cause resolution. - Demonstrated success implementing production cost models, Six Sigma methods, and additional change management processes while transitioning complex systems in multi-contractor environments. - Extensive experience with Technology Development, Transition to Manufacturing, and Full Manufacturing including design-for-manufacturability Original Posting: September 15, 2026 Pay Range: Pay Range $131,300.00 - $237,350.00 The Leidos pay range for this job level is a general guideline onlyand not a guarantee of compensation or salary. Additional factors considered in extending an offer include (but are not limited to) responsibilities of the job, education, experience, knowledge, skills, and abilities, as well as internal equity, alignment with market data, applicable bargaining agreement (if any), or other law.