Mechanical Engineer Fall 2026 Co-Op

Qualifications: Currently pursuing a Bachelor's or Master's degree in Mechanical Engineering, Aerospace Engineering, or a related field. Rising junior, senior, or graduate-level student preferred. Strong academic record with relevant coursework in areas such as mechanical design, propulsion, power systems, or related fields Hands-on experience through lab work, projects, or internships is a plus. Passion for aerospace, defense technology, and innovative engineering solutions. Excellent problem-solving, analytical, and communication skills. Ability to work collaboratively in a fast-paced, team-oriented environment. Preferred

Qualifications: Experience with hardware design, testing, data acquisition, and analysis. Familiarity with missile systems, defense technology, or aerospace components. Strong interest in working in a startup environment with high-impact projects. Why Castelion? At Castelion, you'll be part of a mission-driven company where every project matters. Our interns don't just observe - they contribute meaningfully to the success of our programs. This is a unique opportunity to work at the cutting edge of aerospace engineering while developing the skills and experience that will help you grow into a future leader in the field. 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, the applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (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. This internship is paid at an hourly rate of $30 per hour.

Compensation may vary based on experience and education level. For non-local interns, housing or relocation stipends may be available to help offset temporary living expenses.

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