# Submarine SWFTS Modernization — Program Element 0604503N

**Program element:** 0604503N  
**Component:** U.S. Navy  
**Appropriation:** 1319 — RDT&E, Navy  
**Budget Activity:** 5 — System Development & Demonstration  
**Vintage:** President's Budget PB2027  
**Canonical URL:** https://hitchintel.com/programs/0604503N

## Summary

U.S. Navy requests $195.4M in FY2027, sustained across the five-year plan. In the FY2027 defense authorization, the House funded it in full; the Senate funded it in full; House appropriators funded it in full. General Dynamics leads the industry work.

## Funding profile

| Fiscal Year | Estimate Type | Amount ($M) |
|---|---|---|
| FY2025 | Actual | 94.5 |
| FY2026 | Enacted | 213.8 |
| FY2027 | Request | 195.4 |
| FY2028 | Outyear | 211.6 |
| FY2029 | Outyear | 216.8 |
| FY2030 | Outyear | 214.0 |
| FY2031 | Outyear | 218.2 |

> Estimate types are not summed — the profile mixes actuals, enacted law, the request, and outyear projections.

## Congressional marks (FY2027)

| Stage | Marked ($M) | Change ($M) |
|---|---|---|
| Request | 195.4 | — |
| House NDAA (HASC) | 195.4 | +0.0 |
| Senate NDAA (SASC) | 195.4 | +0.0 |
| House Approps (HAC-D) | 195.4 | +0.0 |

> FY2027 NDAA authorization marks, as of 2026-07-27. Not appropriations or final law.

## Projects (5)

| Project | Title | FY2025 actual | FY2026 enacted | FY2027 request | Move |
|---|---|---|---|---|---|
| 0236 | SSN Comb Cont Sys Imprvmnt (ENG) | 0.0 | 63.2 | 62.1 | −2% |
| 0219 | Sub Sonar Improvement (ENG) | 60.6 | 67.5 | 60.7 | −10% |
| 0253 | Nav & Electro-Optical Supt | 0.0 | 39.3 | 39.4 | +0% |
| 0775 | Submarine Supt Equip Prog | 33.8 | 34.2 | 33.2 | −3% |
| 9999 | Congressional Adds | 0.0 | 9.6 | 0.0 | −100% |

> Projects are the summable leaves: the program element total is their sum, never added to it.

### Project 0236 — SSN Comb Cont Sys Imprvmnt (ENG)

The AN/BYG-1 is the combat control system common across all submarine platforms which incorporates tactical control, weapon/payload control and Tactical Local Area Network (TacLAN) functions into a single procurement program. AN/BYG-1 allows the submarine to rapidly update the ship-safety tactical picture, integrates the common tactical picture into the battlegroup, improves torpedo interfaces, and provides tactical TOMAHAWK, Harpoon, and future payload capability. AN/BYG-1 systems will be continuously updated with hardware enhancements to address Commercial Off The Shelf (COTS) obsolescence and provide capability improvements through software upgrades. Hardware updates are referred to as Tech Insertion (TI) kits and are differentiated by year of development (i.e. TI-22, TI-24, TI-26, etc.). The TI upgrades provide the baseline for all future AN/BYG-1 procurements. AN/BYG-1 is part of the Submarine Warfare Federated Tactical Systems (SWFTS), a family of interdependent systems that conduct cooperative system development and installations. Project Unit 0236: This program develops Commercial-Off-The-Shelf (COTS) based software and hardware upgrades for AN/BYG-1, the Multi-tube Weapons Simulator (MTWS), and the Common Weapon Launcher (CWL) in order to integrate improved tactical and payload control capabilities for all submarine classes. TacLAN provides the infrastructure for connectivity within AN/BYG-1 as well as connectivity to other subsystems attached to TacLAN. It is a local area network backbone for tactical systems on a submarine, including a link to radio for communications off-hull. It enables a submarine to share a common operational picture among systems aboard, and with external platforms. Modifications and improvements to TacLAN are necessary to enable new capabilities requiring network connectivity on BYG-1 and other tactical systems and to improve the submarine's cyber security posture. New capabilities to the Information Assurance (IA) subsystem enhance the centralized solution for cyber security (inclusive of antivirus, access control, intrusion detection and more) and classified information protection (inclusive of posture transition, system downgrade, cross domain solutions and more) onboard all submarines. Modifications to IA are necessary to enable new capabilities on other tactical submarine systems.

**Named R-3 performers** (share of this project's FY2027 R-3 total, so they need not reach 100%)**:** General Dynamics (45.9, 74%), COMOPTEVFOR (0.9, 1.4%).

| Activity (R-2A) | FY2025 | FY2026 | FY2027 |
|---|---|---|---|
| AN/BYG-1 Software Development | 0.0 | 26.7 | 24.6 |
| AN/BYG-1 Hardware Development | 0.0 | 15.7 | 15.2 |
| Testing | 0.0 | 3.4 | 3.5 |
| Payload Development and Test | 0.0 | 10.8 | 10.9 |
| CyberSecurity | 0.0 | 6.5 | 7.8 |

> R-2A activities carry the prior, current and budget year only — no five-year plan. Coverage is partial, so count them, never total them.

### Project 0219 — Sub Sonar Improvement (ENG)

The AN/BQQ-10(V) Acoustic Rapid COTS Insertion (A-RCI) Submarine SONAR system will continue to add new capabilities via Technical Insertion (TI)/Advanced Processing Build (APB) process while working across Submarine Warfare Federated Tactical System (SWFTS) programs to transition to Development Security Operations (DevSecOps) software processes and migrate to a cloud-based architecture. The Navy is pursuing a transformation across SWFTS (PE 0604503N Projects 0219, 0236, 0253 and 0775) to maximize cyber-resiliency and the speed of capability delivery. This program delivers block updates to Sonar Systems installed on SSN 688, 688I, SSN 21, VIRGINIA, SSBN, and SSGN Class Submarines to maintain clear acoustical, tactical, and operational superiority over Submarines and Surface Combatants in all scenarios through detection, classification, localization, and contact following. Acoustics Rapid COTS Insertion (A-RCI) provides multi-phased evolutionary development geared toward addressing acoustic superiority issues through the rapid introduction of interim development products applicable to all Classes of Submarines. - A-RCI Phase I and II introduced Towed Array processing improvements - Phase III introduced Spherical Array processing improvements - Phase IV provided High Frequency (HF) Array processing improvements for SSN 688I, SSGN, SSBN, VIRGINIA, and SSN 21 Class Submarines. As part of the Navy's plan to maintain acoustic superiority for in-service submarines, a joint cooperative effort was established to deliver bi-annual Advanced Processing Builds (APBs) to prevent obsolescence and deliver ongoing capability improvements. - Capabilities in the APBs will be integrated as part of A-RCI certified systems. Sensor Efforts provide increased operational capabilities for littoral operations, situational awareness, and reliability improvements.

**Named R-3 performers** (share of this project's FY2027 R-3 total, so they need not reach 100%)**:** LMC (24.6, 41%), Progeny Systems (7.3, 12%), General Dynamics (5.9, 9.7%), Alion, BAH, AECOM (0.7, 1.1%).

| Activity (R-2A) | FY2025 | FY2026 | FY2027 |
|---|---|---|---|
| APB Productionization | 17.3 | 21.0 | 21.5 |
| Integration and Testing | 39.2 | 42.3 | 35.0 |
| A-RCI Acoustic Superiority Integration | 4.1 | 4.2 | 4.3 |

> R-2A activities carry the prior, current and budget year only — no five-year plan. Coverage is partial, so count them, never total them.

### Project 0253 — Nav & Electro-Optical Supt

AN/BVY-1 Integrated Submarine Imaging System (ISIS) will continue to add new capabilities via the Technical Insertion (TI)/Advanced Processing Build (APB) process while working with partner Submarine Warfare Federated Tactical System (SWFTS) programs to realign software development according to Development Security Operations (DevSecOps) software processes. The Navy is pursuing a cloud enabled containerization architecture transformation across SWFTS (PE 0604503N Project 0219, Project 0236, Project 0253, and Project 0775) to increase operational agility and resiliency at the speed of relevance. FY27 continues to maximize mast RDTE investment and optimizes production through two distinct development programs. First, the New Mast Capability Development Program builds on prior year investment by continuing to insert emerging technologies for future mast module production and begins early design of the Type 2S mast. Second, the Legacy Mast Improvements Program specifically focuses on incorporating mature technologies and design improvements into legacy masts; this effort provides substantial improvements to the large inventory of photonics and imaging masts. Both programs ensure that submarines can conduct operations in high intensity littoral environments, intelligence gathering, real time imagery, and support the safe and effective employment of surveillance and weapons systems. Finally, FY27 funds the TI-24/APB-24 DT and other tests that verify software improvements funded in previous fiscal years. The Navigation and Electro-Optical (E-O) program enables littoral operations by procuring ISIS, the production of low-profile photonics masts (Low Profile Photonics Mast (LPPM), Type 20, and Type 24), the maintenance and sustainment of periscope and legacy photonic masts, the production and sustainment of Universal Modular Mast Systems and Dip Loops, and the development of the ISIS inboard processing components of the Submarine Warfare Federated Tactical System (SWFTS). The Department of the Navy established the ISIS to rapidly field the Type 18 periscope, RADAR rangefinder, Type 8 Mod 4 Infra-red (IR) periscope system, and integrate existing periscope imagery systems into a single imaging system for installation on board SSN 688 class and SEAWOLF class submarines.

**Named R-3 performers** (share of this project's FY2027 R-3 total, so they need not reach 100%)**:** Lockheed Martin (24.0, 61%), L3Harris (9.2, 23%), COMOPTEVFOR (0.3, 0.8%).

| Activity (R-2A) | FY2025 | FY2026 | FY2027 |
|---|---|---|---|
| ISIS and Photonics common software and hardware capabilities development and obsolescence | 0.0 | 29.1 | 29.4 |
| Imaging Systems Test Efforts | 0.0 | 0.8 | 0.8 |
| New Mast Capability Development | 0.0 | 6.7 | 6.7 |
| Legacy Mast Improvements | 0.0 | 2.6 | 2.5 |

> R-2A activities carry the prior, current and budget year only — no five-year plan. Coverage is partial, so count them, never total them.

### Project 0775 — Submarine Supt Equip Prog

AN/BLQ-10 Electronic Warfare (EW) system will continue to add new capabilities via Technical Insertion (TI)/Advanced Processing Build (APB) while working across Submarine Warfare Federated Tactical System (SWFTS) programs to transition to Development Security Operations (DevSecOps) software processes and migrate to a cloud based architecture. The Navy is pursuing a transformation across SWFTS (PE 0604503N Projects 0219, 0236, 0253 and 0775) to maximize cyber-resiliency and the speed of capability delivery. Major capabilities that will be pursued in FY27 include continued development for a Digital Early Warning Receiver (DEWR), upgraded and new tactical software solutions, and continued development of the Submarine Tethered Expendable Buoys (STEB). The Submarine Support Equipment Program (SSEP) is responsible for the development and improvement of submarine EW systems in support of effective operations in the following mission areas: Joint Littoral Warfare; Joint Intelligence Surveillance Reconnaissance (ISR), Indications and Warnings; Electronic Warfare; Information Operations including Cyber; and Special Operations Force (SOF) support. The rapid proliferation of complex radar, communications and navigation equipment available to potential adversaries creates an increasingly dense and sophisticated electromagnetic environment. Sustained and significant improvements to submarine EW systems are required to maintain tactical ship safety and operational effectiveness. As such, EW was raised to a submarine primary mission area in FY2012 by Commander Submarine Forces, and EW is listed as a Tier 1 modernization requirement by the Submarine Tactical Requirements Group (STRG). TI-26 provides a DEWR capability. Additionally, TI-26 looks to improve the basic cloud based architecture developed during TI-22 and TI-24. Funding is critical to developing enabling technologies that will provide maximized electronic spectrum digitization and processing, allowing Submarine EW system to continue to pace the threat. STEB is a 3" Launcher deployed, expendable, free-floating buoy that will communicate with the submarine through a fiber-optic tether providing imaging, Radar Indications and Warning, Radar Direction Finding, and communications. Beginning in FY27, an annual funding line is established for AN/BPS-17 Radio Detection and Ranging (RADAR) improvements.

**Named R-3 performers** (share of this project's FY2027 R-3 total, so they need not reach 100%)**:** Lockheed Martin (25.6, 77%), Ultra Maritime (1.2, 3.7%), OTF (0.2, 0.6%).

| Activity (R-2A) | FY2025 | FY2026 | FY2027 |
|---|---|---|---|
| Submarine Support Equipment Program | 33.8 | 34.2 | 31.9 |
| AN/BPS-17 RADAR Improvements | 0.0 | 0.0 | 1.2 |

> R-2A activities carry the prior, current and budget year only — no five-year plan. Coverage is partial, so count them, never total them.

### Project 9999 — Congressional Adds

Submarine Thin Line Towed Array Enhanced Capabilities funding to support new tasking to design and develop TB-29C Thin-line Extended Length Array modules that include dual tier power components compatible with updated, proven Compact Towed Array (CTA) technology. New design would reinforce TB-29C performance and high reliability minimizing changes to TB-29C modules by integrating power components in every module and retaining proven, high performing, fielded CTA design. This will leverage current power supply and signal path. It will support future configurations (current length and extended length - up to six additional modules).

## Where the FY2027 request goes

| Category | Share | $M |
|---|---|---|
| Industry primes | 75% | 146.3 |
| Government labs & warfare centers | 21% | 40.9 |
| Other / unspecified | 4.2% | 8.1 |

**Top named industry performers:** General Dynamics ($51.8M, 26%), Lockheed Martin ($49.6M, 25%), LMC ($24.6M, 13%), L3Harris ($9.2M, 4.7%), Progeny Systems ($7.3M, 3.7%).

> R-3 exhibit contract funding, not USAspending obligations.

## Mission & acquisition strategy

Submarine Warfare Federated Tactical Systems (SWFTS) is a family of interdependent systems that conduct cooperative system development, procurement, and installations. The SWFTS Participating Acquisition Resource Managers (PARMs) are comprised of PMS401 Acoustic Rapid Commercial Off The Shelf (COTS) Insertion (A-RCI), PMS425 Combat Control (BYG-1), and PMS 435 Integrated Submarine Imaging System (ISIS) and Electronic Warfare (EW BLQ-10). SWFTS Technical Insertion (IT) shipsets must be procured and installed in like quantities (Except EW SSBN (OHIO)) across all PARMs to maintain the SWFTS model.

The Single Acquisition Management Plan (SAMP) for the ISIS Program TI-20/22/24 with Mast is approved 07 Jul 2017. The Program Streamlined Acquisition Plan with Services (PSTRAP-M) for ISIS TI-26/28/30 is approved 08 Mar 2024. The Acquisition Program Baseline Agreement (APBA) for ISIS Program TI-26 Increment with APB-25 & APB-27 is approved 01 May 2024. The ISIS will provide mission critical, all weather, visual, and electronic search, digital image management, indication, warning, and platform architecture interface capabilities for SSN 688, SSN 21, SSN 774, SSN 826 and SSGN class submarines.

## Related program elements

- [0604777N — Navigation/Id System](https://hitchintel.com/programs/0604777N) (Navy)
- [0604274N — Next Generation Jammer (NGJ)](https://hitchintel.com/programs/0604274N) (Navy)
- [0604003F — Advanced Battle Management System (ABMS)](https://hitchintel.com/programs/0604003F) (Air Force)
- [0605649D8Z — Acquisition Integration and Interoperability (AI2)](https://hitchintel.com/programs/0605649D8Z) (Defense-Wide)

## Source & machine access

- **Source:** FY2027 Department of the Navy RDT&E Budget Justification, Exhibits R-2/R-3, PE 0604503N (PB PB2027); FY2027 NDAA committee marks (as of 2026-07-27).
- **MCP:** `mcp.hitchintel.com` — `budget_get_program_element(pe="0604503N")`.

*HitchAI is an independent intelligence service, not affiliated with the U.S. Department of Defense. Budget figures are requests/estimates, not obligations.*