Explore open positions at BlueYard portfolio companies

BlueYard Capital
BlueYard Capital

Senior Propulsion Engineer



Other Engineering
Los Angeles, CA, USA · El Segundo, CA, USA
Posted on Friday, May 17, 2024

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 to deter future conflicts.

Senior Propulsion Engineer

The Senior Propulsion Engineer's primary responsibility is the design of solid rocket motor primary and secondary structures, along with propulsion components, with an emphasis on schedule, affordability and scale.


  • Translate project objectives into cost-effective designs that can be produced at scale – the Castelion way.
  • Spearhead the creation of innovative solid rocket motor designs, demonstrating autonomy even with limited expert guidance.
  • Actively engage in the assembly, testing, and troubleshooting of prototypes and production builds, providing expert guidance as necessary.
  • Use our rapid iteration cycles to validate product performance and facilitate necessary design adjustments.
  • Produce, evaluate, and authorize CAD models and drawings, adhering to internal standards and ASME Y14.5-2009 guidelines.
  • Provide thorough assessments and resolutions for any discrepancies in hardware, including supporting analyses when required.
  • Collaborate with supply chain to ensure seamless support and adapt designs to mitigate availability risks and time delays.

Basic Qualifications

  • Bachelor's or advanced degree in aerospace engineering, manufacturing engineering, materials engineering, mechanical engineering or physics.
  • 5+ years of mechanical or fluids design, analysis, or build experience (student project team, university rocketry club and internship experience counts).
  • Effective communication skills are crucial for collaborating with cross-functional teams, presenting design concepts, and documenting work.

Preferred Skills and Experience

  • Proficient in test methods/setups, with the ability to conduct trade studies using engineering fundamentals to make informed recommendations, even with limited information.
  • Extensive experience working with aerospace materials (including metals, plastics, and composites) and a solid understanding of spacecraft and/or launch vehicle propulsion systems and fluid components.
  • Skilled in CAD software (NX 8.5 or similar packages like PTC Creo, CATIA) with expertise in geometric dimensioning and tolerancing (GD&T) per ASME Y14.5-1994.
  • Relevant experience with rocket motors, solid propulsion elements, and structural interfaces, including knowledge of insensitive munitions protocols and practices.
  • Hold a Master’s degree or PhD in a technical discipline such as mechanical or aerospace engineering.
  • Hands-on experience supporting rapid product development, including designing hardware for high-rate production in alternative non-aerospace domains.
  • Currently hold an active DoD Secret Security Clearance or higher.

Additional Requirements

  • Willing and able to work extended hours and/or weekends with minimal notification to meet critical deadlines leading up to major milestones.
  • Able to travel up to 30% on an ongoing basis

All employees are granted long-term stock incentives as part of their employment as Castelion. All employees receive access to comprehensive medial, 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.