GNC Engineer II, Hypersonics

Firefly Aerospace; Cedar Park (TX); On-site; USD 120,000 - 180,000; Full time

Benefits offered by this job

Health, dental and vision plans

Parental leave

Relocation benefits

Educational reimbursement

Short term disability

Flexible PTO

Job summary

Firefly Aerospace in Texas is seeking a Hypersonics focused GNC Engineer to design, analyze, develop, and test guidance, navigation, and control systems for advanced hypersonic flight vehicles. You will develop GNC algorithms, run high-fidelity simulations, and support flight test activities.

You will collaborate across aerodynamics, propulsion, structures, and flight software, owning algorithms from early development through hardware-in-the-loop testing and flight operations.

Job description

About Firefly Aerospace

Firefly Aerospace is a space and defense technology company that enables our world to launch, land, and operate in space – anywhere, anytime. As the partner of choice for critical space missions, Firefly is the only commercial company to launch a satellite to orbit with 24-hour notice and the only company to achieve a successful Moon landing. Our launch vehicles, lunar landers, and orbital vehicles provide government and commercial customers with full mission services from low Earth orbit to the Moon and beyond. Headquartered in north Austin, Texas, Firefly is looking for passionate, hardworking innovators to join our team and help fuel our successful trajectory into space.

Summary

As a Hypersonics focused GNC Engineer at Firefly, you will design, analyze, develop, and test guidance, navigation, and control systems for advanced hypersonic flight vehicles. In this role, you will develop GNC algorithms and simulation software, perform high-fidelity trajectory and vehicle dynamics analysis, and support integration and flight test activities. You will work across guidance, navigation, controls, aerodynamics, propulsion, flight software, and vehicle systems to develop robust GNC solutions capable of operating in highly dynamic, uncertain, and stressful flight environments. This position offers hands‑on ownership of algorithms and analysis from early vehicle development through hardware‑in‑the-loop testing and flight operations.

Responsibilities

• Develop, implement, and validate guidance, navigation, and control algorithms for hypersonic and high-speed atmospheric flight vehicles.
• Perform 6DOF modeling, simulation, and Monte Carlo analysis across nominal, dispersed, and off-nominal flight conditions.
• Develop and evaluate trajectory guidance, targeting, and optimization algorithms for boost, glide, maneuvering, terminal, and other applicable flight phases.
• Design and tune attitude, flight-path, and vehicle control algorithms considering aerodynamic, propulsion, actuator, and structural constraints.
• Develop navigation and state‑estimation algorithms incorporating IMUs, GPS/GNSS, and other vehicle sensor data.
• Conduct stability, robustness, sensitivity, and uncertainty analyses across highly nonlinear and rapidly changing flight regimes.
• Develop and maintain models of vehicle dynamics, aerodynamics, propulsion, sensors, actuators, atmospheric environments, and other relevant system effects.
• Support software‑in‑the‑loop (SIL), processor‑in‑the‑loop (PIL), and hardware‑in‑the‑loop (HIL) testing and integration of GNC algorithms with flight software and vehicle hardware.
• Analyze ground and flight‑test data to assess GNC performance, correlate vehicle models, identify root causes, and improve future vehicle performance.
• Collaborate with aerodynamics, propulsion, structures, avionics, flight software, systems engineering, and test teams throughout the vehicle development lifecycle.

Qualifications

Required

• Bachelor’s degree in aerospace engineering, mechanical engineering, electrical engineering, physics, mathematics, computer science, or a related technical field.
• 2–5 years of professional experience in guidance, navigation, controls, flight dynamics, trajectory analysis, or a closely related discipline.
• Strong understanding of rigid‑body dynamics, flight mechanics, feedback control systems, and numerical simulation.
• Experience developing or analyzing GNC systems for aerospace vehicles such as hypersonic vehicles, missiles, launch vehicles, reentry vehicles, high‑performance aircraft, or other autonomous flight systems.
• Experience with 3DOF and/or 6DOF vehicle simulation, Monte Carlo analysis, uncertainty propagation, and performance assessment.
• Proficiency with Python, MATLAB/Simulink, or similar tools for modeling, simulation, algorithm development, and data analysis.
• Familiarity with C/C++ and implementation of algorithms in embedded, real‑time, or flight‑critical software environments.
• Understanding of software development practices including Git/version control, code reviews, testing, verification, and technical documentation.

Desired

• Master’s or PhD in aerospace engineering, controls, robotics, applied mathematics, or a related field with emphasis on GNC, flight dynamics, optimization, or autonomous systems.
• Direct experience developing GNC algorithms for hypersonic glide vehicles, boost‑glide systems, maneuvering reentry vehicles, missiles, interceptors, or other high‑speed atmospheric vehicles.
• Knowledge of hypersonic flight dynamics, including aerodynamic nonlinearities, rapidly varying dynamic pressure, atmospheric uncertainty, thermal constraints, and coupled aero‑propulsive effects.
• Experience with trajectory optimization, optimal control, predictive guidance, nonlinear guidance, or real‑time targeting techniques.
• Experience with modern control techniques such as LQR/LQG, gain scheduling, nonlinear control, robust control, adaptive control, or model predictive control.
• Experience with navigation and state estimation, including Kalman filtering, extended/unscented Kalman filters, inertial navigation, GPS/GNSS integration, and sensor fusion.
• Experience developing aerodynamic databases or incorporating CFD, wind‑tunnel, or flight‑test data into vehicle simulations and GNC analysis.
• Experience with SIL, PIL, HIL, real‑time simulation, embedded processors, or flight‑computer integration.
• Familiarity with flight‑test planning, test execution, telemetry analysis, and post‑flight model reconstruction.
• Experience working on defense programs and familiarity with development environments involving ITAR/EAR, classified systems, or U.S. Government customers.

Benefits

Firefly offers outstanding benefits for our employees, including generous health, dental and vision plans with low plan deductibles, parental leave, relocation benefits, educational reimbursement, short term disability, and flexible PTO options.

To conform to U.S. Government space technology export regulations, including the International Traffic in Arms Regulations (ITAR) you must be a U.S. citizen, lawful permanent resident of the U.S., protected individual as defined by 8 U.S.C. 1324b(a)(3), or eligible to obtain the required authorizations from the U.S. Department of State.

Firefly Aerospace, Inc. is an Equal Opportunity Employer; employment with Firefly is governed based on merit, competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.