DOT&E finds modified Mk 48 torpedoes operationally suitable and effect…

A Pentagon report confirms the effectiveness of modified Mk 48 torpedoes. (US Department of Defense)

The US Navy's modified Advanced Processor Build (APB) 5+ Mk 48 torpedo is “operationally effective and suitable”, according to the Director, Operational Test and Evaluation (DOT&E) FY 2023 Annual Report, released on 2 February.

However, “Mk 48 Mod 7 torpedo reliability has degraded below navy-defined requirements”, the DOT&E noted, recommending the navy determine and correct the causes of the degraded reliability of that modified Mk 48.

The Mk 48 is a submarine-launched heavyweight torpedo that directs itself towards a submarine or surface ship based on a set targeting solution.

The torpedo has hardware variants referred to as Mods, with each Mod representing a step improvement in capability, integrating upgraded sensors, guidance and control (G&C), and propulsion system hardware.

Mod 6 features integrated noise quieting in the propulsion section and commercial off-the-shelf (COTS) electronics in the G&C section. Mod 7 features a Common Broadband Advanced Sonar System and an upgraded sonar receiver.

The navy also releases regular software updates, APBs for the torpedoes, which include improved tactics, classification algorithms, and operator interfaces.

“APB 5 modifications focused on detection and discrimination of target submarines and surface ships,” the DOT&E noted. “It also provided an alternative tactic against surface ships. APB 5+ modifications focused on simplifying the interface between the submarine's combat system and the torpedo.”

APB 5+ is limited to Mod 7 torpedo hardware and requires the employing submarine to have the AN/BYG-1 combat control system version APB-18/TI-19 or beyond, according to the DOT&E report.

“Modeling and simulation data confirmed that APB 5+ modifications did not degrade its effectiveness against submarines when compared to APB 5,” the DOT&E added.