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Marine Corps MOS · Aviation

6173 Helicopter Crew Chief, CH-53

Current service use not established

This code is listed in the directory. Inclusion alone does not confirm current service use.

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Overview

CH-53 helicopter crew chiefs serve as flight crew members and answer to the pilot in command while operating the aircraft and its mission and weapons systems. When not scheduled to fly, they inspect, service, maintain, and repair power plants, transmissions, drivetrains, fuel systems, flight controls, and rotor systems.

Minimum clearance: Secret

Minimum ASVAB: EL 105 or GT 105 or MM 105

ASVAB policy: Not policy-reviewed · coverage unknown · as of 2026-10-19

Program scope has not been reviewed.

Policy applicability and coverage of the program's score routes have not been reviewed. Shown-route arithmetic is not an eligibility decision.

Source: navmc-1200-1l-fy26 (source date 2025-03). Policy applicability has not been established.

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Core Skills

  • Helicopter power plant inspection and repair
  • Transmission and drivetrain servicing and repair
  • Flight control and rotor system maintenance

Civilian Career Paths

Career associations are editorial assessments of the cited evidence, not an official crosswalk unless the evidence explicitly says so. O*NET supplies civilian occupation information, not proof of a military match. Related experience does not confer civilian qualifications. Tasks and tools below describe civilian work, not military training.

Aircraft Mechanics and Service Technicians

CH-53 experience inspecting, servicing, maintaining, and repairing power plants, drivetrains, fuel systems, flight controls, and rotors directly supports aircraft maintenance work.

How to prepare: Gather military maintenance records for FAA evaluation toward Airframe and Powerplant ratings: the experience route requires 18 months appropriate to one rating or 30 months concurrently appropriate to both. Applicants must be at least 18, meet English-language requirements, and pass knowledge, oral, and practical tests; approved aviation maintenance schooling or the Joint Service Aviation Maintenance Technician Certification Council course offers an alternative eligibility route, and airlines often require certification even though it is not required for every airline mechanic job.

What the civilian work involves
  • Read and interpret maintenance manuals, service bulletins, and other specifications to determine the feasibility and method of repairing or replacing malfunctioning or damaged components.
  • Examine and inspect aircraft components, including landing gear, hydraulic systems, and deicers to locate cracks, breaks, leaks, or other problems.
  • Conduct routine and special inspections as required by regulations.

Notes & Sources

Evidence for this guidance (3 documents)
  1. NAVMC 1200.1L (FY26, in force): MOS 6173

    [1] MOS 6173 section "a. Summary"; cached text line 50113; NAVMC 1200.1L signed 2025-03-07, in force until 2026-10-01

    Supports: Helicopter power plant inspection and repair, Transmission and drivetrain servicing and repair, Flight control and rotor system maintenance, Aircraft Mechanics and Service Technicians (O*NET 49-3011.00)

  2. O*NET: Aircraft Mechanics and Service Technicians

    [2] O*NET 30.3 occupational data

    Supports: Aircraft Mechanics and Service Technicians (O*NET 49-3011.00)

  3. FAA: Become an Aviation Mechanic

    [3] Requirements and mechanic experience requirements

    Supports: Aircraft Mechanics and Service Technicians (O*NET 49-3011.00)

Defense contractor jobs for 6173

Descriptions may be summarized for clarity. Verify all information with your branch career counselor or official military documentation before making career decisions.

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