Principal Mechanical Engineer - Thermal Engineer

Raytheon; Tucson (AZ); On-site; USD 108,000 - 205,000; Full time

Benefits offered by this job

Parental leave

Flexible work schedules

Educational assistance

Job summary

Raytheon, in Tucson, seeks an experienced Principal Thermal Engineer to lead detailed thermal analyses across products from design trade studies to production support. You will apply hand calculations and finite element methods to solve complex thermal problems, working to ensure cost and schedule adherence.

The role requires presenting results to government customers, planning tests, correlating models, and mentoring analysts.

Qualifications

• Degree in Science, Technology, Engineering or Mathematics (STEM) with 8+ years of relevant experience; Master’s equals 2 years, Ph.D. equals 5 years.
• Experience in thermal analysis with FloTHERM, PATRAN, Thermal Desktop/SINDA or ANSYS.
• Experience applying mechanical principles to solve thermal analysis problems, independently managing priorities.
• Experience in thermal testing: planning, execution, data reduction, and correlation.

Responsibilities

• Perform hand calculations to scope higher-detail analysis models.
• Conduct detailed thermal analyses to address program challenges.
• Generate test plans to validate analyses and ensure hardware compliance.
• Analyze test data to validate and correlate models.
• Lead a team of thermal analysts on major program efforts.

Skills

Thermal analysis

FloTHERM

PATRAN

Thermal Desktop/SINDA

ANSYS

Thermal testing

Team leadership

Security clearance eligibility

Education

Bachelor's degree in STEM

Advanced degree

Tools

CREO CAD

Finite Element Tools

Job description

Date Posted: 2026-09-28

Country: United States of America

Location: US-AZ-TUCSON-805 ~ 1151 E Hermans Rd ~ BLDG 805

Position Role Type: Onsite

U.S. Citizen, U.S. Person, or Immigration Status Requirements: Active and transferable U.S. government issued security clearance is required prior to start date. U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance

Security Clearance Type: DoD Clearance: Secret

Security Clearance Status: Ability to obtain INTERIM U.S. government issued security clearance is required prior to start date

At Raytheon, the foundation of everything we do is rooted in our values and a higher calling – to help our nation and allies defend freedoms and deter aggression. We bring the strength of more than 100 years of experience and renowned engineering expertise to meet the needs of today’s mission and stay ahead of tomorrow’s threat. Our team solves tough, meaningful problems that create a safer, more secure world.

The Mechanical Analysis and Test (MA&T) Department is responsible for ensuring structural and thermal design robustness across the Raytheon portfolio of products. From preliminary concepts to fielded weapon system support, MA&T delivers innovative structural and thermal engineering solutions utilizing methods ranging from classical fundamental & empirically based techniques to state-of-the-art finite element methods leveraging industry leading commercial tools; all complimented and validated by tests executed in a manner to ensure cost effective yet technically balanced solutions.

Raytheon is seeking an experienced Principal Thermal Engineer to join the MA&T Department. The Thermal Engineer is responsible for detailed thermal analysis on products throughout their lifecycle from initial design trade studies and proposals through qualification testing to enduring production support. The analyses will cover a wide range of difficult problems, requiring solutions that are imaginative, thorough, practicable, and consistent with organization objectives. The analysis tasks will span the spectrum from classical hand analyses to detailed analyses requiring the use of finite element analysis software. A Thermal Engineer of this salary grade is expected to have a level of technical competence with thermodynamic principles. The Thermal Engineer will be held accountable for completing his/her work within the agreed upon cost and schedule. Additionally, the selected candidate will be expected to present their work for peer reviews and to be a peer reviewer for other engineers’ work. Finally, the engineer is expected to plan and support tests, perform data reduction and engage in thermal model correlation.

What You Will Do

• Perform Hand Calculations to determine scope of higher detail analysis models
• Perform detailed thermal analyses to solve various program thermal challenges
• Generate test plans required to validate analyses and verify hardware compliance to customer requirements
• Analyze test data to validate and correlate models
• Work with experienced analysts on problems of moderate complexity to provide the answers needed under program cost and schedule constraints
• Review your work with peers to ensure technical accuracy
• Present results to internal, external, and government customers
• May travel to government and other facilities in support of program activities
• Generate detailed documentation of work and archive for reference
• Act as a technical leader (help define/refine and/or develop MA&T department technical processes and tools) and/or lead analysis/test teams

Qualifications You Must Have

• Typically requires a degree in Science, Technology, Engineering or Mathematics (STEM) and a minimum of 8 years of prior relevant experience unless prohibited by local laws/regulations. An advanced degree in a related field may be substituted for additional years of experience as follows: Master’s is equal to 2 years of experience or a Ph.D. is equal to 5 years of experience
• Experience in thermal analysis with any of the following tools: FloTHERM, PATRAN, Thermal Desktop/SINDA or ANSYS or equivalent
• Experience in mechanical principles to solve classical thermal analysis solutions both inside and outside of finite element tools and an ability to work independently and manage multiple priorities
• Demonstrated experience in thermal testing: Planning, organization, execution, data reduction and correlation
• Demonstrated experience in leading a team of thermal analysts on major program efforts
• Ability to obtain a U.S. government issued security clearance. U.S. citizenship is required, as only U.S. citizens are eligible for a security clearance, Clearance must be active and transferable prior to start date

Qualifications We Prefer

• Advanced degree.
• 10+ years of professional experience in the thermal analysis of complex systems that require collaboration of multiple engineering disciplines
• Experience with solid modeling CAD tool such as CREO or equivalent
• Experience in Electronics Cooling and Aerodynamic Heating Analyses
• Demonstrated experience in leading thermal testing: Planning, organization, execution, data reduction and correlation
• Earned Value Management System knowledge
• Experience in supporting EACs, BOEs and proposals
• Experience presenting to external customers
• Ability to travel to government and other facilities in support of program activities
• Advanced degree in aforementioned disciplines. ABET is the preferred, although not required, accreditation standard

RTX Corporation is an Aerospace and Defense company that provides advanced systems and services for commercial, military and government customers worldwide. It comprises three industry-leading businesses – Collins Aerospace Systems, Pratt & Whitney, and Raytheon. Its 185,000 employees enable the company to operate at the edge of known science as they imagine and deliver solutions that push the boundaries in quantum physics, electric propulsion, directed energy, hypersonics, avionics and cybersecurity. The company, formed in 2020 through the combination of Raytheon Company and the United Technologies Corporation aerospace businesses, is headquartered in Arlington, VA.

What We Offer

Whether you’re just starting out on your career journey or are an experienced professional, we offer a robust total rewards package with compensation; healthcare, wellness, retirement and work/life benefits; career development and recognition programs. Some of the benefits we offer include parental (including paternal) leave, flexible work schedules, achievement awards, educational assistance and child/adult backup care.

As part of our commitment to maintaining a secure hiring process, candidates may be asked to attend select steps of the interview process in-person at one of our office locations, regardless of whether the role is designated as on-site, hybrid or remote.

The salary range for this role is 107,500 USD - 204,500 USD. The salary range provided is a good faith estimate representative of all experience levels. RTX considers several factors when extending an offer, including but not limited to, the role, function and associated responsibilities, a candidate’s work experience, location, education/training, and key skills.

Hired applicants may be eligible for benefits, including but not limited to, medical, dental, vision, life insurance, short-term disability, long-term disability, 401(k) match, flexible spending accounts, flexible work schedules, employee assistance program, Employee Scholar Program, parental leave, paid time off, and holidays. Specific benefits are dependent upon the specific business unit as well as whether or not the position is covered by a collective-bargaining agreement.

Hired applicants may be eligible for annual short-term and/or long-term incentive compensation programs depending on the level of the position and whether or not it is covered by a collective-bargaining agreement. Payments under these annual programs are not guaranteed and are dependent upon a variety of factors including, but not limited to, individual performance, business unit performance, and/or the company’s performance.

This role is a U.S.-based role. If the successful candidate resides in a U.S. territory, the appropriate pay structure and benefits will apply.

RTX anticipates the application window closing approximately 40 days from the date the notice was posted. However, factors such as candidate flow and business necessity may require RTX to shorten or extend the application window.

RTX is an Equal Opportunity Employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability or veteran status, or any other applicable state or federal protected class. RTX provides affirmative action in employment for qualified Individuals with a Disability and Protected Veterans in compliance with Section 503 of the Rehabilitation Act and the Vietnam Era Veterans’ Readjustment Assistance Act.