Principal Engineer

Job Posting Start Date 09-04-2025 Job Posting End Date 09-10-2025

Flex is the diversified manufacturing partner of choice that helps market-leading brands design, build and deliver innovative products that improve the world.

A career at Flex offers the opportunity to make a difference and invest in your growth in a respectful, inclusive, and collaborative environment. If you are excited about a role but don't meet every bullet point, we encourage you to apply and join us to create the extraordinary.

Job Summary

JETCOOL Technologies a Flex company is a fast-moving cooling solution provider, and successful MIT-spinoff, producing game-changing cooling solutions for aerospace, electric vehicles, and data centers. We are looking for a Principal Engineer based in Littleton, Ma.

What a typical day looks like:

• Work with JetCool commercial team to adapt customer requirements into an implementation ready design.
• Advance technology maturity of new secondary system design elements (water quality, flow regulation etc.).
• Work with manufacturing partners to establish modular design specifications for fast customer implementation and deployment.
• Lead communication and technical exchange with customers, build and cultivate customer and partner relationships, focusing on behind and beyond the rack cooling infrastructure
• Work with Flex supply chain to enable vendors and ensure specifications are up to date.
• Lead technical problem solving and pull in cross functional team to provide innovative thermal cooling system solutions

The experience we're looking to add to the team:

• Bachelor (or higher) of Science (B.S. in mechanical or aerospace engineering) and 5+ years of work experience and 2+ years thermal heat rejection architecture / infrastructure experience  
• Excellent first principles knowledge in mechanical engineering, fluid dynamics, thermodynamics, and system heat transfer
• Track record of delivering thermal heat rejection solutions to customers with high quality and on schedule
• Strong communication skills
• Strong problem-solving and thermal / fluid system analysis skills
• Ability to specify smart heat rejection system architectures

What you'll receive for the great work you provide:

• Full range of medical, dental, and vision plans
• Life Insurance
• Short-term and Long-term Disability
• Matching 401(k) Contributions
• Vacation and Paid Sick Time
• Tuition Reimbursement

Pay Range (Applicable to Massachusetts)

$147,700.00 USD - $203,100.00 USD Annual

Job Category

Production Engineering

Is Sponsorship Available?

No

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