Senior Avionics Harness Design Engineer

About Castelion

Castelion is bringing a new approach to defense development and production: one that focuses on short, iterative design cycles, rapid testing in development, and modern commercial manufacturing strategies for production at scale. We're designing, building, and testing next generation long range strike weapons systems to give America and its Allies a definitive edge and deter future conflicts.

Senior Avionics Harness Design Engineer

We are seeking a Senior Avionics Harness Design Engineer to lead the design, development, and integration of electrical harnessing across our missile and vehicle systems. This engineer will play a critical role in ensuring robust, manufacturable, and high-reliability electrical connectivity throughout the system. You will partner closely with avionics, power, structures, and propulsion teams to deliver mission-critical hardware in a fast-paced, hardware-rich environment. You will additionally support avionics and harness integration at the system and vehicle levels.

Responsibilities

• Design, route, and document electrical harnesses to support missile and vehicle system integration
• Generate wiring diagrams, schematics, and harness assembly drawings in accordance with aerospace standards
• Select appropriate wires, connectors, backshells, shielding, and protection materials to meet environmental and system requirements
• Collaborate with avionics, power, and structural engineering teams to ensure proper integration of harnesses into overall vehicle design
• Develop and maintain harness BOMs (bill of materials) and ensure manufacturability at scale
• Support harness build, installation, and troubleshooting during integration and testing
• Ensure designs meet electrical, mechanical, and thermal requirements for high-reliability aerospace applications
• Identify and implement process improvements to increase efficiency, manufacturability, and quality

Basic Qualifications

• Bachelors or Masters degree in Electrical Engineering, Mechanical Engineering, Aerospace Engineering, or related field
• 2+ years of experience in cable harness design for aerospace, defense, or high-reliability hardware systems
• Proficiency with CAD/ECAD tools for harness design (e.g., CATIA, Creo, SolidWorks Electrical, Capital, RapidHarness, AutoCAD, or equivalent)
• Strong knowledge of aerospace wiring standards (e.g., IPC/WHMA-A-620, NASA-STD-8739, or MIL-SPEC requirements)
• Familiarity with harnessing in environments with high thermal and small volume requirements
• Hands-on experience supporting harness manufacturing, assembly, and testing
• Ability to work cross-functionally with avionics, power, propulsion, and integration teams
• Strong problem-solving and troubleshooting skills in test and integration environments

Why Castelion

• Opportunity to design and deliver mission-critical harnessing for next-generation missile systems
• Work alongside a team of A+ players who believe in the mission and want to make a difference
• Be part of a rapidly growing startup where your impact is direct and visible
• Competitive compensation, equity, and benefits package

All employees are granted long-term stock incentives as part of their employment as Castelion. All employees receive access to comprehensive medical, vision, and dental insurance, and the company offers three weeks of paid time off per year.

Leadership Qualities

Bias to Action and Creative Problem Solving. Desire and experience questioning assumptions in ways that lead to break through ideas that are ultimately implemented. Successfully bring in applicable processes/concepts/materials from other industries to achieve efficiency gains. Ability to personally resolve minor issues in development without requiring significant support.

High Commitment, High Initiative. A successful candidate will have a genuine passion for Castelion's mission and consistently look for ways to contribute to the company's technical goals and prevent hardware blockers. Ability to work in a fast paced, autonomously driven, and demanding atmosphere. Strong sense of accountability and integrity.

Clear Communicator. Proactively communicates blockers. Trusted in previous roles to be voice of company with regulators, suppliers, gate keepers and customers. Capable of tactfully managing relationships with stakeholders to achieve company-desired outcomes without compromising relationships. Emails, IMs and verbal interactions are logical, drive clarity, and detailed enough to eliminate ambiguity.

ITAR Requirements:

· To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State.

Employment with Castelion is governed on the basis of competence and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.