Lightweight Torpedo Development

Abstract

The Lightweight Torpedo (LWT) program designs, integrates and tests the MK 54 LWT and supports an incremental developmental acquisition approach combining hardware and Advanced Processor Build (APB) software upgrades to enable rapid fielding of improvements to the fleet. The program will focus on common LWT and Heavyweight Torpedo (HWT) hardware and software architecture enhancements that will provide improvements to the array, warhead, propulsion, and APB software to address capability gaps against challenging adversary submarines and environments. Future APB software builds will utilize common torpedo software to deliver capability and tactics improvements to the MK 54 LWT. The program will also support development of enhanced weapon delivery methods, including the high altitude launch of the MK 54 from the P-8A Maritime Patrol and Reconnaissance Aircraft (MPRA) with the HAAWC Air Launch Accessory (ALA) and development of a common HAAWC capability compatible with the MK 54 MOD 2 Advanced LWT (ALWT). The HAAWC development program provides the P-8A MPRA with the ability to release LWTs from high altitude to prosecute enemy submarine threats. Operational Testing (OT) was conducted at the end of FY 2020, and the Commander Operational Test & Evaluation Force (COMOPTEVFOR) report was issued in FY 2021, recommending fielding. Follow-on T&E (FOT&E) was conducted in FY 2022 with updated flight control software and the program delivered the HAAWC capability to the fleet in Q3 FY 2022 with Commander Patrol and Reconnaissance Group (CPRG) declaring Initial Operating Capability (IOC) in Q1 FY 2023. The current HAAWC design was developed to deploy the MK 54 MOD 0/1. The MK 54 MOD 2 is not compatible with HAAWC due to having different mass properties and outer mold line from the MK 54 MOD 0/1 LWT. The HAAWC development program will focus on development of a new HAAWC design, starting in FY 2024, that will be compatible, at a minimum, with the MK 54 MOD 2 ALWT, aligned with the MK 54 MOD 2 fleet delivery schedule and investigate the potential for a common HAAWC design for all MK 54 MODs. The MK 54 MOD 1 provides significant performance improvements compared to MK 54 MOD 0 for challenging littoral, shallow water environments and adversary countermeasures. The MOD 1 program is split into 2 increments: Increment 1 focusing on the updated sonar hardware and associated APB 5 common software to provide an improved LWT to the Fleet to replace the MK 54 MOD 0s; Increment 2 is the APB 6 software (SW) only upgrade to fully take advantage of the improved sonar hardware developed under Increment 1, update the platform interface to reduce Fleet Operator workload, and provide new potential capabilities such as Salvo and terminal homing improvements. APB 6 will run on MOD 1 but also serves as the SW baseline for the MK 54 MOD 2 and the MOD 2 program will leverage development and testing under the MOD 1 Increment 2 program to reduce the scope of the test and evaluation required for the MOD 2. The MK 54 MOD 2 improves the lethality and speed of the LWT by upgrading the Warhead and Propulsion system to counter challenging near-peer adversary submarines that are faster and deeper diving, leveraging the sonar hardware improvements developed under the MOD 1 program. The program awarded four Other Transaction Authority (OTA) agreements to industry partners in FY 2020 for the Proof of Design (POD) of the Guidance and Control (G&C) section, Warhead, Stored Chemical Energy Propulsion System (SCEPS) afterbody sections, and All Up Round (AUR) system integrator. Industry partners are focused primarily on the development of torpedo hardware and support equipment while the USN maintains the responsibility of developing the software under the APB process and will develop specific software modules for the MK 54 MOD 2 variant. To make the program more affordable in the Proof of Manufacture (POM) Phase while still delivering necessary capability to the Fleet, the program has restructured to an incremental approach, first focused on delivering the lethality required for the intended threats. In the first increment, the program is prioritizing the G&C and Warhead development and their integration with existing LWT Otto fuel propulsion section. Increment 2 will complete the development and integration of the capability delivered by the SCEPS section and meet the full requirements defined by the Capability Development Document (CDD). Each increment will have its own test and evaluation phase and IOC. Increment 1 is focused on meeting the lethality requirements at its IOC and Increment 2 is expected to meet the full set of system requirements (as defined in the CDD) at its IOC. The program intends to award a competitive OTA in FY 2024 to a single AUR Industry partner. The winner of the OTA will complete POM of the Increment 1 AUR and procure up to the equivalent of 48 POM AUR test assets to be used in the Increment 1 Developmental and Operational Test and Evaluations. The winner of the Increment 1 OTA will be responsible for managing the subsystem and system level qualification, AUR assembly, and platform integration. Increment 2 will be competed and awarded in FY2030 and will be expected to complete development and integration of the Increment 2 AUR and procurement of POM AUR test assets to be used for the Increment 2 Developmental and Operational Test and Evaluations.

Document Details

• Document Type: R2 Budgetary Justification
• Publication Date: Oct 01, 2025
• Source ID: 0604610N_5_1319_PB_2025
• Change Summary Explanation: FY 2023 funding request was adjusted by ($3.795M) due to SBIR/STTR realignment. FY 2025 total decrease of $86.821M is due to a reduction in the MK 54 MOD 2 development technical approach, a reduction in Phase II hardware development, and minor rate adjustments.
• Service Agency Name: Navy

Entities

Organizations

• United States Navy

Tags

Readers

• Aerospace Engineering
• Enterprise Information Systems Architecture and Joint Command Capability Interoperability Support.
• Naval Mine Countermeasure Systems Development.