Principal Systems Engineer

Accelint is a mission-driven technology company focused on strengthening national security and supporting critical industries. We build the technologies that help operators and organizations see what’s happening, make faster and better decisions, take action with confidence, and stay ready for what comes next. Our work includes advanced sensors, autonomous systems, mission command and control software, AI-enabled training and simulation, and tools that improve logistics, maintenance, and overall readiness.  

For nearly 30 years we have supported military and civilian agencies across the Department of Defense, U.S. allies and partners, and essential industries. When you join Accelint, your work directly contributes to protecting national security and strengthening the systems our society depends on.  

The Principal Systems Engineer serves as the technical authority for complex systems development efforts, providing end-to-end systems engineering leadership across requirements development, design, integration, verification, and delivery. This role is responsible for driving technical excellence, overseeing subcontractor performance, mentoring engineering teams, and supporting business development activities through proposal and customer engagement.

Key Responsibilities

• Lead the development, decomposition, and management of system, subsystem, and interface requirements in alignment with customer needs and program objectives.
• Collaborate with the engineering team to ensure requirements are traceable, verifiable, and aligned with mission performance.
• Participate in subsystem architecture trades to balance performance, cost, schedule, and risk.
• Review and approve technical approaches to ensure designs meet requirements and integrate cleanly at the system level.
• Provide technical oversight and direction to subcontractors and suppliers delivering hardware, software, and system elements.
• Review subcontractor designs, analyses, test plans, and test results for compliance with requirements and interfaces.
• Review and approve subcontractor technical artifacts, including requirements, designs, test plans, and deliverables.
• Serve as a technical interface between subcontractors, internal engineering teams, and government stakeholders.
• Actively participate in technical reviews, ensuring technical rigor and risk mitigation with subcontractors and customers.
• Mentor and develop junior and mid-level engineers, fostering strong systems engineering practices and technical growth.
• Promote consistency in systems engineering processes, tools, and best practices across programs.
• Foster a culture of continuous learning, technical curiosity, and accountability.
• Support proposal and capture efforts by contributing technical approaches, requirements understanding, and engineering cost estimates.
• Write technical content including white papers, technical sections of proposals, status reports, and internal documentation.
• Deliver effective internal and external technical briefings.
• Engage with customers and partners to understand technical needs and communicate SIE’s engineering capabilities.

Required Qualifications

• Bachelor’s degree in Systems Engineering, Electrical Engineering, Mechanical Engineering, Computer Engineering, or a related technical field (Master’s preferred).
• 10+ years of experience in systems engineering across complex, multidisciplinary systems.
• Demonstrated ability to lead technical teams and influence across organizational boundaries.
• Experience managing requirements, interfaces, and technical baselines throughout the system lifecycle.
• Strong written and verbal communication skills, including experience with customer and executive-level briefings.

Preferred Qualifications

• Active or ability to obtain a security clearance (if applicable).
• Experience with subcontractor technical management.
• Familiarity with Model-Based Systems Engineering (MBSE) and modern SE tools.
• Experience in defense, aerospace, or other highly regulated technical environments.

Clearance Requirements 

Some positions will require access to U.S. National Security information.  Positions that require this access w