Sr. Manufacturing Engineer, Composites

About the role

Castelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus and technical excellence are decisive advantages—and we are building a team that can deliver real capability, not just concepts. This is a rare opportunity to join at an early stage, where your work will directly shape critical systems, influence major technical decisions, and have immediate, real-world impact.

Castelion is seeking a highly skilled Senior Manufacturing Engineer to establish in-house manufacturing capability for composite components. This will include qualifying build processes, releasing mature work instructions, producing tooling, and training operators. This role will be responsible for delivering flight-ready composite hardware produced through internal Castelion manufacturing processes.

Responsibilities

• Develop, validate, and implement manufacturing processes for composite structures, including layup, vacuum bagging, curing, trimming, bonding, and assembly operations.
• Design and develop production tooling, fixtures, molds, and manufacturing aids required for in-house production.
• Generate and release work instructions, process specifications, and manufacturing documentation.
• Troubleshoot manufacturing issues and drive improvements in quality, yield, throughput, and cost.
• Lead the transition of composite components from development and external suppliers to internal production.
• Establish process controls, manufacturing standards, and inspection requirements to ensure consistent product quality.
• Support equipment selection, factory development, and workflow optimization to enable efficient composite manufacturing.
• Partner with design and materials engineering teams to provide DFM feedback and ensure products are designed for manufacturability and production success.
• Support development, qualification, and implementation of new composite materials, tooling concepts, and manufacturing methods.
• Work cross-functionally with design, quality, supply chain, procurement, and program management to meet performance, schedule, and cost objectives.

Qualifications

Basic Qualifications

• Bachelor's or advanced degree in aerospace engineering, manufacturing engineering, materials engineering, mechanical engineering, or physics.
• 3+ years of experience building aerospace-grade composite components from scratch.

Skills

Preferred Skills and Experience

• Experience in a hardware development environment.
• Previous involvement in a high-speed production environment, handling flight hardware.
• Prior involvement in a high-output environment, involving hands-on experience in constructing composite components.
• Ability to acclimate to frequently changing assignments and a fast-paced working environment.
• Excellent communication skills, both written and oral, along with effective teamwork abilities.
• Superb focus and attention to detail, with remarkable work efficiency and accuracy.
• Use of hand tools, power tools, and fabrication tools.
• Expertise in manufacturing and repairing intricate testing systems.
• Familiarity with Atlassian tools such as SVN, Confluence, and JIRA.
• Skills in project management.

Benefits

• Employee Equity: Meaningful equity for all full-time employees—share value has increased 150x in three years.
• Personal Time Off: Four (4) weeks of paid time off to unplug, reset, and come back sharp—velocity matters, burnout doesn’t.
• Company Paid Holidays: Ten (10) company-paid holidays.
• Medical: Plans at 100% employee-covered and 80% of dependent coverage.
• Dental & Vision: 90% covered for employees and 80% for dependents to ensure access to quality preventive and ongoing care.
• FSA/HSA: Options to set aside pre-tax dollars for eligible medical and dependent care expenses.
• Retirement: 401k plan to support long-term financial growth.
• Paid Parental Leave: Birthing parents are eligible for up to 10 weeks of paid leave; non-birthing parents may take up to 4 weeks. Additional paid pregnancy leave for CA employees.
• Meals & Catering: Frequently catered lunches and team meals, plus company-covered meals when extra time or effort is required.
• Snacks & Beverages: Fully stocked kitchen with unlimited snacks and drinks.
• Performance & Fitness: $100 monthly fitness stipend to support peak performance and health.
• EV Charging: Onsite electric vehicle charging available for employees.

Physical Demands

• Must be willing to work extended hours and/or weekends as needed.
• Must be able to travel up to 30%.
• Must be able to lift more than 50 lbs.

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.

This position may require access to classified information or restricted U.S. Government sites, systems, or information. If so designated, your employment may be contingent upon obtaining and maintaining the required U.S. Government security clearance or other authorization, and satisfying citizenship or other eligibility requirements. Failure to obtain or maintain any required clearance or authorization may result in reassignment, leave, or separation from employment.