Lead, Mechanical Engineer (Thermal) - Space Optics

L3Harris•Fort Wayne, FL

11d•Onsite

About The Position

L3Harris is seeking an experienced and highly accomplished Lead Thermal Engineer to lead spacecraft‑level thermal design, modeling, and analysis activities for advanced space based electro-optical missions. This role is responsible for architecting and validating thermal solutions that ensure mission success across multiple orbital environments. The ideal candidate is a recognized technical expert capable of driving complex spacecraft thermal strategy, mentoring engineers, and collaborating across multidisciplinary teams.

Requirements

Bachelor of Science Degree in Engineering and a minimum of 9 years of prior relevant experience. Graduate Degree in Engineering and a minimum of 7 years of prior related experience. In lieu of a degree, minimum of 13 years of prior related experience.
5+ years professional experience using Thermal Desktop
Prior or current professional experience with thermal design and analysis for space environment/products
2+ years of experience as an IPTL or providing technical leadership to an engineering team

Nice To Haves

Experience designing for a space environment.
Hold a current security Clearance or the ability to obtain a security clearance
Deep understanding of spacecraft materials, thermal coatings, MLI, conductive interfaces, and active thermal control elements.
Demonstrated success in developing, validating, and correlating thermal models to TVAC results.
Ability to lead design reviews, guide complex decision-making, and communicate clearly with customers, leadership, and engineering teams.
Experience working on government, DoD, or national security space missions.
Knowledge of mission-specific environments such as GEO, LEO, cislunar, or deep space.
Broad knowledge of thermal-fluids physics including heat conduction and convection of multi-phase flows
Experience creating and overseeing the development of thermal testing control logic in SINDA/FLUENT
Familiarity with structural-thermal-optical (STOP) analysis, deployment mechanism thermal behavior, or thermal considerations in RF/high‑power payloads.
Experience with reliability assessments, derating, and long‑duration thermal performance modeling.

Responsibilities

Serve as the technical lead for spacecraft‑level thermal design, defining architecture, strategies, and requirements for high‑reliability space vehicles.
Develop detailed thermal models and analyses for all mission phases, including worst‑case hot/cold environments, eclipse conditions, orbital variations, and mission‑specific scenarios.
Lead creation and validation of thermal control hardware—including radiators, coatings, heat pipes, surface finishes, insulation, heaters, and conductive interfaces.
Own thermal performance budgets and flow‑down of requirements to payloads, avionics, structures, and propulsion subsystems.
Evaluate thermal impacts of system trades, configuration changes, power profiles, and operational timelines.
Direct development of thermal math models using industry-standard tools such as Thermal Desktop, SINDA/FLUINT, ESATAN‑TMS, or equivalent.
Provide leadership during spacecraft hardware build, integration, and test—including thermal vacuum (TVAC) planning, execution, anomaly resolution, and correlation of test results to analysis.
Guide environmental considerations for space platforms including radiation, conduction, convection-free behavior, material properties, surface degradation, and mission life effects.
Act as a cross-functional leader, collaborating closely with systems engineering, mechanical design, power, RF, digital hardware, manufacturing, and mission assurance teams.
Mentor junior and mid‑level engineers, establishing best practices and driving continuous improvement in thermal engineering processes.
Prepare high‑quality documentation including thermal requirements, analysis reports, review packages, test plans, and verification matrices.
Ability to obtain a US security clearance