US Navy moves ahead with light torpedo programmes

The US Navy (USN) is getting ready for testing and other milestones throughout this year for its lightweight torpedo (LWT) and very lightweight torpedo (VLWT) programmes.

The navy intends to complete the Initial Operational Test and Evaluation (IOT&E) for MK 54 Mod 1LWT and High-Altitude Anti-Submarine Warfare (ASW) Weapon Capability (HAAWC) in fiscal year (FY) 2021, the Pentagon Director, Operational Test and Evaluation (DOT&E) noted in its annual report released in January 2021.

The USN is also expected to release a request for proposals (RFP) in mid-2021 for the VLWT.

“The MK 54 lightweight torpedo is the most capable ASW (anti-submarine warfare) weapon used by US surface ships, fixed-wing aircraft, and helicopters,” the DOT&E reported.

HAAWC provides an adapter wing kit that allows aircrews to deploy an MK 54 from a P-8A Multi-mission Maritime Aircraft from higher than traditional altitudes. The wing kit glides the MK 54 to a water entry point directed by the P-8A combat system.

The MK 54 Mod 1 includes a new sonar array that provides higher resolution than previous MK 54 variants, DOT&E noted. “Software modifications exploit the additional capability provided by the new sonar array.”

The MK 54 Mod 1 uses Advanced Processor Build (APB) 5 software that shares many components with the APB 5 variant of the MK 48 heavyweight torpedo.

Expected to deliver an Early Operational Capability in FY 2026, the MK 54 Mod 2 will feature a new propulsion system and warhead. However, the MK 54 Mod 2 is not compatible with the current Vertical Launch Anti-Submarine system or HAAWC systems. Also, the MK 54 Mod 1 torpedo is not approved for the VLA rocket. The current MK 54 Mod 0 and MK 54 Mod 0 Block upgrade variants support the VLA.