CFD Trajectory Sim Engineer

Firehawk is a leading propulsion-focused aerospace and defense company located in Addison, TX. Our innovative approach empowers us to design and manufacture cutting‑edge solid and hybrid rocket motors and engines. We aim to push the boundaries of propulsion technology to serve both commercial and defense sectors.

Seeking an experienced CFD / Trajectory Sim Engineer to lead analysis, design, and verification of advanced aerospace systems, with a particular emphasis on solid rocket motor performance. You will own end‑to‑end simulation and control tasks: from internal flow and nozzle CFD to aerodynamic modeling, and trajectory analysis.

This role is ideal for someone who is comfortable switching between detailed physics‑based modeling (including propulsion and aerodynamics) and system‑level analysis, and who can provide technical leadership on complex, multi‑disciplinary projects involving solid rocket motors and flight vehicles.

• Lead aerodynamic and aerothermal analysis for vehicles (e.g., launch vehicles, spacecraft, UAVs, missiles). o Perform CFD analyses of solid rocket motors, including:
• Internal flow through grain geometry, ports, and chambers.
• Nozzle flow (subsonic, transonic, supersonic) and expansion characteristics.
• Coupled internal/external flow interactions where applicable. o Develop, run, and validate CFD models for internal and external flows (steady/unsteady, compressible, turbulent, reacting if applicable).
• Generate and manage high‑quality meshes (chamber, grain, nozzle, plumes); perform grid convergence, sensitivity, and uncertainty analysis. o Analyze thrust, specific impulse, nozzle efficiency, and flow‑induced loads; provide derived parameters and aero/propulsion databases for GNC and structures.
• Correlate CFD results with static fire test data, wind tunnel data, and/or flight test data; refine models based on discrepancies.
• Trajectory Simulation o Develop and maintain high‑fidelity trajectory simulation tools for aerospace or defense platforms.
• Model vehicle dynamics, atmospheric effects, propulsion performance, possible guidance and control behavior, and environmental constraints. o Perform Monte Carlo simulations, sensitivity studies, and performance margin assessments.
• Analyze flight test or experimental data and correlate results with simulation models. o Generate mission‑level analyses, including launch windows, flight envelopes, aerodynamics, and range safety considerations.
• Systems & Collaboration o Serve as a technical leader, mentoring junior engineers and reviewing CFD analyses, Trajectory analysis, and code.
• Work closely with propulsion engineers on grain design, performance prediction, and test correlation for solid rocket motors. o Present findings, risks, and recommendations to engineering leadership and program management.
• Contribute to requirements definition, verification plans, and documentation of models and codes.

• Bachelor in Aerospace Engineering, Mechanical Engineering, Applied Physics, or a related field.
• 5+ years of relevant industry or research experience in CFD and/or Trajectory sim for aerospace systems.
• Demonstrated experience with CFD applied to propulsion systems, ideally solid rocket motors (internal flow, nozzle CFD, plume, or related work).
• Strong proficiency with at least one major CFD tool (e.g., ANSYS Fluent, CFX, STARCCM+, OpenFOAM, SU2).
• Solid background in fluid dynamics, aerodynamics, and numerical methods (RANS, LES, compressible flow, high Mach regimes).
• Experience with 3 DOF and 6 DOF simulation on launch vehicles.
• Strong skills in MATLAB/Simulink and at least one programming language (Python, C/C++, or Julia).
• Experience with version control (Git), model verification, and rigorous…