Senior Thermal Engineer — Defense Systems Thermal Architect

Next Matter; Torrance (CA); On-site; USD 120,000 - 180,000; Full time

Benefits offered by this job

Equity (long-term)

4 weeks PTO

10 company-paid holidays

Health benefits including medical

Parental leave

Fitness stipend

EV charging on site

Catered meals and fully stocked pantry

Job summary

Castelion is seeking a Senior Thermal Engineer to own the thermal engineering methodology across missile systems. You will define thermal architectures, develop high-fidelity thermal models, and use first-principles analysis, simulation, and hardware testing to ensure our vehicles perform reliably in demanding environments.

You’ll work across aerodynamics, structures, electrical, propulsion, systems, manufacturing, and test engineering to develop integrated thermal solutions from concept through

Qualifications

• BS or higher degree in Aerospace Engineering, Mechanical Engineering, or Applied Physics.
• Strong understanding of heat transfer, fluid dynamics, and high-temperature environments.
• 5+ years of experience in aerospace thermal engineering on rocket, spacecraft, aircraft, or missile programs.
• Experience with electronic unit thermal analysis and control to component junctions.
• Ground testing experience with thermal instrumentation and data acquisition.
• Strong programming skills in MATLAB, Python, or similar for tool development.
• Experience preparing formal documentation.
• CAD experience with SolidWorks or Siemens NX.
• Ability to obtain and hold a U.S. security clearance.

Responsibilities

• Thermal design and analysis of unmanned air vehicles at conceptual, preliminary, and detailed design maturities.
• Define thermal system architectures and material selection strategies for vehicles operating in demanding flight environments.
• Thermal analysis of flight vehicles using standard thermal analysis codes and engineering/hand methods.
• Transient thermal analysis for time-varying mission profiles.
• Ground test planning, execution, and analysis in specialized thermal test facilities.
• Flight test planning, execution, and post-flight thermal data analysis.
• Use first principles and MATLAB/Python models to inform design decisions.
• Collaborate with aerodynamics, structures, electrical, and systems engineers on integrated solutions.
• Present thermal status at formal reviews internally and with customers.
• Prepare formal documentation (specifications, test procedures, technical reports).

Skills

Heat transfer

Fluid dynamics

High-temperature environments

MATLAB

Python

First principles analysis

Modeling & simulation

Team collaboration

Education

BS in Aerospace Engineering

MS in Aerospace/Mechanical Engineering

Tools

SolidWorks

Siemens NX

Thermal Desktop/SINDA

Data acquisition

Job description

Castelion is seeking a Senior Thermal Engineer to own the thermal engineering methodology across missile systems. You will define thermal architectures, develop high-fidelity thermal models, and use first-principles analysis, simulation, and hardware testing to ensure our vehicles perform reliably in demanding environments.

You’ll work across aerodynamics, structures, electrical, propulsion, systems, manufacturing, and test engineering to develop integrated thermal solutions from concept through