OVERVIEW: The Mk67 SLMM Mod 2 is a submarine-launched mobile bottom mine based on a modified Mk37 torpedo, designed for precision covert emplacement in constrained or shallow waters. It is launched from standard torpedo tubes and navigates to a pre-programmed target location before arming as an influence mine.

DETAILS: The Mk67 Submarine-Launched Mobile Mine (SLMM) Mod 2 was introduced in 1988 as an upgrade to the original Mod 1 system. It retains the Mk37 torpedo body but features improved inertial navigation and reliability enhancements for higher-precision delivery. After launch, it travels autonomously along a pre-set path, then halts and rests on the seabed, functioning as a bottom influence mine. Mod 2 improvements addressed accuracy and performance limitations identified in Mod 1 trials. The mine is designed for covert mining of ports, straits, or enemy harbor approaches where direct aerial delivery is infeasible or too risky.

FUNCTION: Launched from submarine torpedo tubes, the Mod 2 SLMM maneuvers to a designated target location underwater and arms itself after stopping on the seafloor. It acts as a persistent barrier mine triggered by acoustic or magnetic influence signatures.

NOTE:
IOC: 1988
Operators: United States Navy
Platforms: Los Angeles-class submarines and other SSNs with 21-inch torpedo tubes
Conflict used in: No confirmed combat use

SOURCE: U.S. Navy Mine Warfare Manual ; Jane’s Naval Weapon Systems ; Federation of American Scientists (FAS): https://fas.org/man/dod-101/sys/sea/mk67.htm ; Naval Sea Systems Command technical publications ; https://www.navy.mil