Senior Mechanisms Engineer - Fluids & Pumps

K2 is building the largest and highest-power satellites ever flown, unlocking performance levels previously out of reach across every orbit. Backed by $450M from leading investors including Altimeter Capital, Redpoint Ventures, T. Rowe Price, Lightspeed Venture Partners, Alpine Space Ventures, and others - with an additional $500M in signed contracts across commercial and US government customers - we're mass-producing the highest-power satellite platforms ever built for missions from LEO to deep space.

The rise of heavy-lift launch vehicles is shifting the industry from an era of mass constraint to one of mass abundance, and we believe this new era demands a fundamentally different class of spacecraft. Engineered to survive the harshest radiation environments and to fully capitalize on today's and tomorrow's massive rockets, K2 satellites deliver unmatched capability at constellation scale and across multiple orbits.

With multiple launches planned through 2026 and 2027, we're Building Bigger to develop the solar system and become a Kardashev Type II (K2) civilization. If you are a motivated individual who thrives in a fast-paced environment and you're excited about contributing to the success of a groundbreaking Series C space startup, we'd love for you to apply.

The Role

Critical to achieving K2's vision is deploying our 20-kW high-power spacecraft platform at scale across MEO, GEO, cis-lunar, and deep space. Realizing that vision means actively controlling the heat generated by the high-power payloads our platform hosts. This requires active thermal control systems such as pumped fluid loops, built from fluid turbopumps, valves, accumulators, and pressure and temperature instrumentation. Scaling to constellations requires someone who can span the mechanical, fluid, electromechanical, and thermal-fluid domains and collaborate closely with the thermal, avionics, software, and production teams to deliver these systems at rate.

As Senior Mechanisms Engineer, Fluids & Pumps, you will define how K2 designs, manufactures, tests, integrates, and deploys precision turbopumps and the supporting mechanisms of the active thermal control system. You will own these systems from concept through integration and rate production. You will be responsible for mission-critical hardware which goes to space.

Responsibilities

• Responsible for turbopumps and supporting fluid-loop mechanisms of the spacecraft active thermal control system, including:

• • Architectural down-selection, design, and tolerancing

• • Pump- and mechanism-specific analyses (rotor dynamics, bearings and seals, hydraulic performance, structural, thermal-fluid)

• • Environmental test and qualification plans

• • Ground- and in-flight performance validation plans

• • Supply chain and high-volume manufacturing trades

• Partner with the thermal and platform architecture teams to scope the long-term K2 pumped-fluid-loop roadmap, and system performance requirements

• Collaborate with thermal, structures, avionics, and satellite bus teams to determine optimal operations and requirements for the pump, supporting mechanisms, and broader fluid loop

• Prepare design reviews to secure stakeholder buy-in and communicate expectations across hardware, software, test, and manufacturing teams

• Own and refine program deliverables and schedules throughout development and production

• Evaluate and select manufacturing equipment for specialty processes (impeller machining, rotating-assembly balancing, leak/flow test)

• Partner with production to develop work instructions, in-process checkouts, and end-of-line tests

Qualifications

• Bachelor's degree in mechanical, aerospace, or other relevant engineering discipline

• 5+ years of experience with mechanical and/or electromechanical design and analysis

• 2+ years of experience design and analysis of mechanisms, pumps, or other fluid systems

• Experience with CAD or FEA software packages

Nice to Have

• Experience designing, building, and testing centrifugal or axial pumps for closed-loop thermal systems, including impeller geometry, volute/diffuser design, and hydraulic performance prediction

• Experience with NASA-STD-5017, SMC-S-016, and GSFC-STD-7000 for the design and qualification of in-space Moving Mechanism Assemblies

• Experience with bearing analysis, preload techniques, and preload measurement

• Experience with the practical application of GD&T

• Demonstrated ability to own moving mechanism assemblies across the full product lifecycle in a high velocity environment

• Demonstrated understanding of structural analysis and failure modes of complex mechanical systems in space environments and operations

• Independent and self-motivated mindset, with strong organizational, written, and oral communication skills across disciplines

Compensation and Benefits:

• Base salary range for this role is $140,000 - $175,000 + equity in the company

• Salary and level will be based on several factors including, but not limited to: knowledge and skills, education, and experience level

• Comprehensive benefits package including paid…