MACHINIST'S MATE (WEAPONS) (MMW)

OVERVIEW

Machinist's Mate (Weapons) — MMW — operates and maintains the strategic-weapons mechanical systems aboard Ohio-class SSBNs and SSGNs — the Mk-48 ADCAP torpedo handling and stowage systems, the Tomahawk multiple-all-up-round canister mechanical interfaces, and the Trident SLBM tube mechanical systems. MMWs are the strategic-weapons mechanical specialists.

The submarine community is an all-volunteer force that operates the Navy's nuclear-powered fast-attack, guided-missile, and ballistic-missile submarines. Sailors must qualify in submarines (earning the Silver or Gold Dolphins) and operate under unique deployment cycles, watchbills, and the demanding Submarine Force standards established by Admiral Hyman G. Rickover.

A-school for the rating runs ~14 weeks at Trident Training Facility, Kings Bay, GA / Bangor, WA, where Sailors complete the technical foundation needed to report to their first fleet command. Entry requires the ASVAB line score VE+AR+MK+AS=210 and an enlistment obligation of 6–6 years. MMWs advance through the standard enlisted paygrade structure (E-1 through E-9), competing in the Navy-Wide Advancement Examination (NWAE) at E-4 through E-6 and via the Selection Board at E-7 through E-9. Senior MMWs typically serve as Leading Petty Officer (LPO), Work Center Supervisor, Leading Chief Petty Officer (LCPO), or Command Master Chief (CMC), and may pursue Limited Duty Officer (LDO), Chief Warrant Officer (CWO), or commissioning programs such as STA-21, MECP, or OCS.

Across the active force, MMW Sailors are essential to the Navy's mission readiness, and the rating remains an in-demand career field with strong reenlistment bonuses (SRB), advancement opportunities, and pathways into Navy Reserve, civilian DoD, and industry careers after service.

WHAT MMWs DO

MMWs operate and maintain torpedo tubes and weapons-handling equipment, the Trident missile tube mechanical components, the Tomahawk MAC mechanical interfaces, and conduct weapons stowage, transfer, and handling for every submarine ordnance evolution.

RESPONSIBILITIES

• MMWs operate and maintain torpedo tubes and weapons-handling equipment, the Trident missile tube mechanical components, the Tomahawk MAC mechanical interfaces, and conduct weapons stowage, transfer, and handling for every submarine ordnance evolution.
• Stand watches and qualify on the rating's Personnel Qualification Standards (PQS), maintain training jackets, and mentor junior MMWs as required by the chain of command.
• Lead the MMW work center as Leading Petty Officer or Work Center Supervisor — managing maintenance documentation in 3M/MFOM, parts ordering, and personnel qualifications.
• Support general military training (GMT), damage control, force protection, and watch-bill assignments common to every Sailor regardless of rating.

HISTORY

Machinist's Mate (Weapons) is the modern designator for the submarine torpedo and strategic-weapons mechanical track, branched from the legacy Torpedoman's Mate (TM) and Machinist's Mate (MM) submarine community.

The submarine rating lineage traces to the commissioning of USS Holland in 1900 and the establishment of the Submarine Force the same year. Modern submarine enlisted ratings were redefined under Admiral Hyman G. Rickover in the 1950s as the Navy transitioned from diesel-electric to nuclear propulsion with USS Nautilus (SSN-571).

Today the Machinist's Mate (Weapons) (MMW) rating is overseen by the Enlisted Community Management (ECM) office at My Navy HR and the Center for Personal and Professional Development. Modern MMWs benefit from the Sailor 2025 personnel-system reforms, the Ready Relevant Learning (RRL) training continuum, and credentialing through the Navy COOL program — turning rating qualifications into industry-recognized certifications and licenses.

The rating's structure, training pipeline, and operational employment continue to evolve alongside the Navy's transition to Distributed Maritime Operations (DMO), Project Overmatch, and the Force Design 2045 fleet architecture, ensuring MMWs remain central to the warfighting mission.

TRAINING PIPELINE

1. 1. Recruit Training (Boot Camp)~10 weeks
   Naval Station Great Lakes, IL
   Initial entry training for all U.S. Navy enlisted Sailors at the Navy's only boot camp.
2. 2. Machinist's Mate (Weapons) A-School~14 weeks
   Trident Training Facility, Kings Bay, GA / Bangor, WA
   Submarine pipeline rating training (includes Basic Enlisted Submarine School)
3. 3. Fleet / Operational TourFirst sea or operational tour
   Ohio (SSBN/SSGN-726) class submarines
   On-the-job training and qualifications in the MMW rating with a fleet unit.

TYPICAL CAREER PATH

1. E-1/E-3
   Apprentice MMW
   A-school in the submarine pipeline; first tour with a fleet unit.
2. E-4/E-6
   Petty Officer MMW
   Lead a Machinist's Mate (Weapons) work-center, qualify in core watchstations and platform-specific tasks.
3. E-7+
   Chief Machinist's Mate (Weapons)
   Senior enlisted leader of the rating in the command; instructor, detailer, or department leading chief assignments.

TYPICAL PLATFORMS & UNITS

• Ohio (SSBN/SSGN-726) class submarines
• Virginia (SSN-774) class submarines
• Los Angeles (SSN-688) class submarines

EXAMPLE NECs

• MMW-4233 Submarine Weapons Mechanical Maintainer

RELATED RATINGS

• MMA · Submarine Force
  Machinist's Mate (Auxiliary)
• MT · Submarine Force
  Missile Technician
• GM · General Surface & Combat
  Gunner's Mate

RELATED BASES

• Navy Base · GA
  Naval Submarine Base Kings Bay
• Navy Base · WA
  Naval Base Kitsap
• Navy Base · CT
  Naval Submarine Base New London

FREQUENTLY ASKED QUESTIONS

SOURCES

• Navy Machinist's Mate (Weapons) (navy.com)
• My Navy HR — Enlisted Community Management
• Navy COOL — Rating Detail