Principal Avionics Engineer

Portal Space Systems is on a mission to expand humanity’s freedom of movement in space. We’re building the spacecraft that makes that mission possible. From our Bothell, WA headquarters, we design vehicles with the maneuverability, resilience, and adaptability needed for the next era of orbital operations. Every system we build is in service of a simple idea: space should be more accessible, responsive, and capable.

Joining Portal means stepping into a team that believes in bold engineering, fast iteration, and the power of small groups to change what’s possible. If you want your work to directly shape the future of in-space mobility, join us.

Position Summary

The Staff / Principal Avionics Engineer is the technical lead and responsible engineer for the avionics subsystem across the full product lifecycle, from concept through qualification, integration, launch, and on-orbit operations. The role owns the flight computer, command and data handling, data bus networks, and electrical power system electronics, and implements a modernized, software-defined, Modular Open Systems Approach (MOSA)–compliant avionics architecture built on Integrated Modular Avionics (IMA) principles.

This individual contributor role works closely with flight software, GNC, systems engineering, and mechanical engineering.

Core Responsibilities

• Define and own the avionics architecture as a software-defined Integrated Modular Avionics (IMA) platform with MOSA-compliant modular hardware and standardized interfaces.
• Own the flight computer and command and data handling (C&DH) design, including processors, FPGAs, memory, storage, and fault tolerance.
• Define the onboard data network and interfaces, including data bus architecture, time distribution, sensor and actuator I/O, and payload interfaces.
• Own the electrical power system electronics, including solar array regulation, battery management, power distribution and switching, point-of-load regulation, and fault protection.
• Partner with flight software on hardware/software partitioning, hardware abstraction, and resource allocation for the software-defined platform.
• Own avionics reliability and radiation analysis, including part selection, derating, worst-case analysis, FMEA, and COTS radiation mitigation.
• Set electronic design standards and lead schematic and PCB design reviews for reliability, manufacturability, and EMI/EMC.
• Lead avionics design reviews (SRR, PDR, CDR, TRR) and own avionics requirements, specifications, and interface control documents.
• Define and execute avionics verification and qualification, including environmental testing, electrical ground support equipment, Flat Sat, and hardware-in-the-loop testbeds.
• Provide hands-on support for integration and test, launch operations, and on-orbit anomaly resolution.
• Manage avionics component and board-level suppliers.
• Provide technical guidance and mentorship to avionics engineers.

What You Bring To Portal

• Demonstrated experience leading the full development lifecycle of an avionics subsystem on at least one flight program.
• Strong technical judgment in electrical design trades, power budgeting, signal and power integrity, grounding and bonding, EMI/EMC, and component selection.
• Ability to architect modular, software-defined avionics with standardized hardware interfaces and partitioned computing resources.
• Demonstrated ability to decompose complex, loosely defined work into clear tasks that can be executed personally or delegated.
• Ability to provide technical direction, resolve technical conflicts, and influence decisions across disciplines without direct authority.
• Clear written and verbal communication for design reviews, anomaly investigations, test readiness reviews, and program-level technical discussions.

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