Senior GNC Engineer (Navigation)

STEM Boomerang; Rio Rancho (NM); On-site; USD 140,000 - 190,000; Full time

Benefits offered by this job

Equity for all full-time employees

4 weeks paid time off

Medical: 100% employee coverage

Dental & Vision: 90% employee coverage

FSA/HSA options

401k plan

Paid parental leave: up to 10 weeks

Onsite EV charging

Job summary

Castelion is seeking a Senior GNC Engineer to develop advanced navigation solutions for long-range hypersonic strike vehicles. You will design, analyze, implement, and validate multi-sensor navigation algorithms, including star-tracker-based navigation, in a fast-paced, hardware-driven setting.

The role focuses on precise state estimation across mission phases, including GPS-denied environments, with collaboration across multidisciplinary teams and real-time embedded systems.

Qualifications

• Bachelor's, Master's, or PhD in Aerospace, Electrical, or related field.
• 5+ years in navigation algorithm development, analysis, and validation for aerospace or high-performance dynamic systems.
• Strong background in estimation theory, including EKF and multi-sensor fusion.
• Experience with INS and integration with external aiding sources (GNSS, star trackers).
• Familiarity with GPS-denied navigation (alt-nav) techniques.
• Proficiency with modeling/simulation tools like MATLAB/Simulink; real-time implementation.
• Experience with 3DOF/6DOF simulation environments and sensor error modeling.

Responsibilities

• Develop, analyze, implement, and validate multi-sensor navigation algorithms.
• Work with multidisciplinary teams in a hardware-driven environment.
• Explore star-tracker-based alternative navigation and sensor fusion architectures.
• Ensure precise state estimation across all mission phases, including GPS-denied environments.

Skills

Estimation theory

EKF

Multi-sensor fusion

INS integration

GNSS

Star trackers

Alt-nav

MATLAB/Simulink

3DOF/6DOF sim

Sensor error modeling

Embedded systems

Flight software integration

Education

Bachelor's/Master's/PhD in Aerospace or Electrical Eng

Tools

MATLAB/Simulink

Job description

Rio Rancho, United States | Posted on 08/06/2026

Castelion was founded to restore America’s ability to field advanced weapons at speed and scale. Inspired by the engineering urgency of the WWII and Apollo eras, we combine rapid iteration, vertical integration, and scalable manufacturing to deliver affordable, high-performance strike systems. Our mission: rebuild industrial agility to strengthen national security and outpace evolving threats.

About the Role:

We are seeking a Senior GNC Engineer to develop advanced navigation solutions for Castelion's long-range hypersonic strike vehicles. This role is critical to enabling precise state estimation across all mission phases, including GPS-denied environments. You will work hands-on with multidisciplinary engineering teams to design, analyze, implement, and validate multi-sensor navigation algorithms, including star tracker-based alternative navigation and sensor fusion architectures, in a fast-paced, hardware-driven environment.

Requirements

• Bachelor's, Master's, or PhD in Aerospace Engineering, Electrical Engineering, or related field
  
• 5+ years of experience in navigation algorithm development, analysis, and validation for aerospace or high-performance dynamic systems
  
• Strong background in estimation theory, including Extended Kalman Filters (EKF) and multi-sensor fusion
  
• Experience with inertial navigation systems (INS) and integration with external aiding sources (e.g., GNSS, star trackers, or similar sensors)
  
• Familiarity with alternative navigation (alt-nav) techniques for GPS-denied environments
  
• Proficiency in modeling and simulation tools such as MATLAB/Simulink or equivalent
  
• Experience with 3DOF and 6DOF simulation environments and real-time implementation of navigation algorithms
  
• Strong understanding of sensor error modeling (IMUs, star trackers, etc.) and calibration techniques
  
• Familiarity with flight software integration and real-time embedded systems
  
• Strong problem-solving mindset, thriving in a fast-paced, hardware-rich, high flight cadence environment
  
• Employee Equity: Meaningful equity forall full-time employees - share value has increased 150x in three years
  
• Personal Time Off: Four (4) weeks of paidtime off to unplug, reset, and come back sharp—velocity matters,burnout doesn't
  
• Medical: We offer plans at 100% employeecovered and 80% of dependent coverage
  
• Dental & Vision: We cover 90%employees and 80% for dependents to ensure you and your family haveaccess to quality preventive and ongoing care
  
• FSA/HSA: To support long-term health andfinancial resilience, we offer FSA and HSA options that allowemployees to set aside pre-tax dollars for eligible medical anddependent care expenses
  
• Retirement: 401k plan offered to supportlong term financial growth along side high-impact, high-velocity work
  
• Paid Parental Leave: We support growingfamilies with meaningful time to bond and recover. Birthing parentsare eligible for up to 10 weeks of paid leave, while non-birthingparents may take up to 4 weeks of paid leave. This time can be usedfor pre-natal care, pregnancy, childbirth, and related medicalneeds—ensuring every parent has the support they need during thisimportant life moment.8-weeks of paid parental leave for allparents. Additional paid pregnancy leave for CA employees
  
• Meals & Catering: Frequently cateredlunches and team meals, plus company-covered meals when extra timeor effort is required
  
• Snacks & Beverages: Fully stockedkitchen with unlimited snacks and drinks to keep you fueledthroughout the day
  
• Performance & Fitness: $100 monthlyfitness stipend to support peak performance and health, both insideand outside of work
  
• EV Charging: Onsite electric vehiclecharging available for employees