Mechanical Engineering Intern (Summer 2027)

Castelion Corporation•Allen, TX

About The Position

Castelion is hiring a Mechanical Engineering Intern for Summer 2027 to contribute to the design, testing, and integration of next-generation missile systems. The role offers a hands-on experience in a fast-paced, collaborative startup environment, with work supporting advanced defense technologies and the development lifecycle from design and prototyping through testing and final integration. Interns collaborate with engineering, manufacturing, and test teams and receive mentorship from experienced aerospace and defense professionals. The position may require access to classified information or restricted U.S. Government sites, systems, or information. If designated, employment may depend on obtaining and maintaining required government clearance or authorization and meeting applicable eligibility requirements. Employment is also contingent on the candidate being able to access applicable export-controlled information without additional export licensing.

Requirements

Currently pursuing a bachelor's or master's degree in Mechanical Engineering, Aerospace Engineering, or a related field.
Strong academic record with relevant coursework, such as mechanical design, propulsion, or power systems.
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.
Ability to access applicable export-controlled information without additional export licensing.
If the role is designated as requiring government clearance or authorization, ability to obtain and maintain it and meet applicable citizenship or other eligibility requirements.

Nice To Haves

Rising junior, senior, or graduate-level student.
Hands-on experience through lab work, projects, or internships.
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.

Responsibilities

Assist in the design, analysis, and testing of components for missile subsystems, including propulsion, guidance systems, and power electronics.
Support engineering teams with simulations, modeling, and prototyping of hardware components.
Conduct research and development tasks, gathering and analyzing data to inform design decisions.
Participate in system integration, including assembling and testing subsystems in real-world test environments.
Collaborate with engineering, manufacturing, and test teams to support project success.
Document design processes, test results, and project progress.
Attend technical reviews, design meetings, and team briefings.