It takes hard work and smarts to get you into the reactor room. But if you have a strong interest in math, chemistry, physics and engineering, you might just have what it takes to be a Machinist's Mate Nuclear. As an MMN, you are the Navy's nuclear reactor mechanic. It is your responsibility to perform all maintenance on the steam-powered propulsion plants aboard aircraft carriers and submarines to ensure our fleet can move safely. And your hard work can lead to great rewards. As an MMN, you'll be eligible to receive up to a $50,000 bonus for first-time enlistment. Re-enlistment bonuses are also available. Think you have what it takes to make a nuclear-powered ship run?

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What to Expect

Machinist's Mate Nuclear

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Responsibilities

Nuclear Machinist's Mates operate and maintain steam turbines and reduction gears used for nuclear ship propulsion and auxiliary machinery such as turbogenerators, pumps and oil purifiers. They also maintain auxiliary machinery outside of main machinery spaces, such as electrohydraulic steering engines and elevators, refrigeration plants, air conditioning systems and desalinization plants. They may also operate and maintain compressed gas producing plants. Nuclear-trained MMs perform duties in nuclear propulsion plants operating reactor control, propulsion and power generation systems.

Work Environment

As a Machinist's Mate Nuclear, you'll have the opportunity to work at sea or ashore. Your assignment could also place you in an intense, fast-paced environment aboard a nuclear-powered submarine or aircraft carrier.

Learn more about submarine service and life on a ship.

Training & Advancement

Upon completion of initial training at Recruit Training Command Great Lakes, (known as Boot Camp), those pursuing a Machinist's Mate Nuclear role report to "A" School in Charleston, SC, for six months. Here, they develop a working knowledge of technical mathematics and power distribution. Students learn to solve basic equations using phasors, vector notations and basic trigonometry and analyze DC and AC circuits. They also learn how to operate electrical equipment using controllers, and how to properly test, maintain, troubleshoot, and repair electrical circuits, motors and other related electrical equipment.

From there, MMNs move on to Naval Nuclear Power School (NNPS), also in Charleston, SC. Here they learn theory and practical application of nuclear physics and reactor engineering. The six-month course provides a comprehensive understanding of a pressurized-water Naval nuclear power plant, including reactor core nuclear principles, heat transfer and fluid systems, plant chemistry and materials, mechanical and electrical systems, and radiological control.

Following NNPS, MMNs begin prototype training in their rating specialty at one of two Nuclear Power Training Units (NPTUs) - located in Charleston, SC, and Ballston Spa, NY. This six-month course teaches the fundamentals of a Naval nuclear power plant and the interrelationship of its mechanical, electrical, and reactor subsystems. Students develop oral communications skills, obtain an understanding of nuclear radiation, and gain knowledge of the safe operation of a complex Naval nuclear power plant.

In Nuclear Operations, promotion opportunities are regularly available but competitive and based on performance.

Post-Service Opportunities

It's also important to note that specialized training received and work experience gained in the course of service can lead to valuable credentialing and occupational opportunities in related fields in the civilian sector.

Education Opportunities

Beyond offering access to professional credentials and certifications, Navy technical and operational training for a Machinist's Mate Nuclear can translate to credit hours toward a bachelor's or associate degree through the American Council on Education.

You may also continue your education through undergraduate degree opportunities like the Navy College Program and Tuition Assistance and the Post-9/11 GI Bill.

Qualifications & Requirements

A high-school diploma or equivalent is required to become an Enlisted Sailor and Machinist's Mate Nuclear in the Navy. Those seeking a role as a Machinist's Mate Nuclear must be U.S. citizens with successful completion of one year of Algebra, and who can meet eligibility requirements for a security clearance.

General qualifications may vary depending upon whether you're currently serving, whether you've served before or whether you've never served before.

Part-Time Opportunities

There are no part-time jobs as a Navy Reserve Sailor in this role. Go back to Careers to find other jobs that have a Reserve component. You can also find out more about what life is like as a Reserve Sailor in the Navy.

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