Over-the-Horizon Backscatter Radar

Mission — Over-the-Horizon Backscatter Radar source

Efforts funded in this PE focus on development, testing, and fielding, of a long-range early detection capability for airborne and surface targets of interest. Each line of effort acquires and fields a land based, high-frequency (HF) ionospheric backscatter radar for over the horizon detection and tracking of airborne and surface targets over wide geographic areas. Fielding of this capability will enable detection, tracking and reporting of airborne and surface targets that may be obscured from conventional line of sight radar systems by the curvature of the earth. Specific lines of effort funded include, but are not limited to, Tactical Multi-Mission Over the Horizon Radar (TACMOR), Homeland Defense Over the Horizon Radar (HLD-OTHR) and support for a classified EUCOM requirement. TACMOR capability is being developed for employment in the Republic of Palau (RoP) to provide enhanced Air Domain Awareness in the USINDOPACOM area of responsibility. TACMOR will be located in the RoP and operated by the United States in agreement with the RoP. Development, test and evaluation, and acquisition of the system and associated components will provide warfighters with the capability to close gaps in surveillance coverage in key regions of the Pacific area of interest to the United States and its Allies. HLD OTHR efforts are focused on the development of a capability to extend current NWS surveillance to long range early warning for North America in response to emerging threats. The programs intent is to design, develop, test and field advanced OTHR systems operating at levels of sensitivity far exceeding current US OTHR systems in operation. Program activities include C2 interface design and integration, HF sensor and digital receiver technology advancement, ionospheric characterization research, remote sensor management capability development, and sensor data fusion research. HLD-OTHR data will be distributed and integrated into existing integrated air and missile defense (IAMD) early warning networks, to include the emerging DAF Battle Network and Cloud Based C2 architectures as applicable. In support of the Air and Cruise Missile Defense of the Homeland mission and NORAD/USNORTHCOM Defense of North America mission, the project will continue to focus investments to enhance capability for Over-the-Horizon Radars. The planned activities to development, acquire, and field HLD OTHR system in FY26 are classified. HLD OTHR will continue executing experimental efforts with the DoD science and technology community to characterize ionospheric conditions in CONUS locations. This program is in Budget Activity 7, Operational System Development because this budget activity includes development efforts to upgrade systems that have been fielded or have received approval for full rate production and anticipate production funding in the current or subsequent fiscal year. The FY24 President's Budget requested this BPAC move to Budget Activity 5, System Development and Demonstration (SDD) to support the current acquisition strategy at that time. The Congressional defense committees approved the change but due to database errors, the change never took effect. This program element may include necessary civilian pay expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in PE 0605827F, 0605828F, 0605829F, 0605831F, 0605832F, 0605833F, 0605898F, 0606398F. In FY2024,1.100M was expended for civilian pay expenses in this program element, and in FY2025, 1.900M is forecasted for civilian pay expenses in this program element. The FY 2025 funding request was reduced by 1.647 million to account for the availability of prior year execution balances. This program is in Budget Activity 7, Operational System Development because this budget activity includes development efforts to upgrade systems that have been fielded or have received approval for full rate production and anticipate production funding in the current or subsequent fiscal year.

Mission — HLD - OTHR source

HLD-OTHR efforts focus on the development of a capability to extend current NWS surveillance to long range early warning for North America in response to emerging threats. The intent of the program is to design, develop, test and field advanced 6th generation OTHR systems operating at levels of transmit power and receiver sensitivity that should exceed current OTHR systems in operation. Program activities include C2 interface design and integration, HF sensor and digital receiver technology advancement, ionospheric characterization research, remote sensor management capability development, and sensor data fusion research. HLD-OTHR data will be distributed and integrated into existing integrated air and missile defense (IAMD) early warning networks, to include the emerging DAF Battle Network and Cloud Based C2 architectures as applicable. The emphasis of the work performed in this program are to evaluate and develop improvements to the OTHR sensors tracking algorithms to increase probability of detection of high-altitude air vehicles such as stratospheric balloons and other unidentified aerial phenomena. Fielding involves land-based installation of Transmit and Receive site arrays for bi-static operations. Additional development will include the establishment of an initial Operations Control Center (OCC) capability and associated Command and Control Battle Management to enable the dissemination of track data and other targets of interest for Air and Cruise Missile Defense of the Homeland (ACMD-H) air domain awareness requirements. Program Element will also be utilized to fund any emerging or urgent joint operational OTHR needs as required. This program element may include necessary civilian pay expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in program element 0605827F, 0605828F, 0605829F, 0605831F, 0605832F, 0605833F, 0605898F, 0606398F. In FY24 4.2M was expended for civilian pay expenses in this program element, and in FY25 4.3M is forecasted for civilian pay expenses in this program element. This program is in Budget Activity 5, System Development and Demonstration (SDD) because it has passed Milestone B approval and is conducting engineering and manufacturing development tasks aimed at meeting validated requirements prior to full rate production.

Mission — Over-the-Horizon Backscatter Radar source

Efforts funded in this PE focus on development, testing, and fielding, of a long-range early detection capability for airborne and surface targets of interest. Each line of effort acquires and fields a land based, high-frequency (HF) ionospheric backscatter radar for over the horizon detection and tracking of airborne and surface targets over wide geographic areas. Fielding of this capability will enable detection, tracking and reporting of airborne and surface targets that may be obscured from conventional line of sight radar systems by the curvature of the earth. Specific lines of effort funded include, but are not limited to, Tactical Multi-Mission Over the Horizon Radar (TACMOR), Homeland Defense Over the Horizon Radar (HLD-OTHR) and support for a classified EUCOM requirement. TACMOR capability is being developed for employment in the Republic of Palau (RoP) to provide enhanced Air Domain Awareness in the USINDOPACOM area of responsibility. TACMOR will be located in the RoP and operated by the United States in agreement with the RoP. Development, test and evaluation, and acquisition of the system and associated components will provide warfighters with the capability to close gaps in surveillance coverage in key regions of the Pacific area of interest to the United States and its Allies. The total cost of the TACMOR Middle Tier of Acquisition effort is 243.4 million, including RDT&E and procurement of prototype units. TACMOR is not fully funded across the Future Years Defense Program. The Department of the Air Force is assessing all options to address the funding shortfalls for MTA programs including additional funding in a future budget request, performance trades based on technical maturity, or transition to alternative pathways. HLD-OTHR efforts focus on the development, testing, and fielding of capabilities to extend current NWS surveillance of long-range early warning for North America in response to emerging threats. The primary mission of the new HLD-OTHR systems will be to provide long-range sensor coverage of potential air and cruise missile threats to North America, with secondary and tertiary capability against complex targets of interest (i.e, High Altitude Balloons) and maritime surface vessels and additional tasking as required. The system will be comprised of four OTHR systems and an Operational Control Center. HLD-OTHR data will be distributed and integrated into existing air, missile and maritime defense early warning networks, as applicable. This project will continue to focus investments to enhance capability for the Air and Cruise Missile Defense of the Homeland mission. The FY 2025 funding request was reduced by 1.647 million to account for the availability of prior year execution balances. This program element may include necessary civilian pay expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in PE 0605827F, 0605828F, 0605829F, 0605831F, 0605832F, 0605833F, 0605898F, 0606398F. In FY2023, 4.2M was expended for civilian pay expenses in this program element, and in FY2024, 4.3M is forecasted for civilian pay expenses in this program element. FY26 PB $132.067M funding and budget justification has been submitted in PE 0102417F, Budget Activity 07 due to a database error. DAF will internally correct this error prior to submission of the FY27 PB and all OTHR efforts will continue in this updated exhibit executing in Budget Activity 05. No Congressional action is requested to correct this technical error. This program is in Budget Activity 5, System Development and Demonstration (SDD) because it has passed Milestone B approval and is conducting engineering and manufacturing development tasks aimed at meeting validated requirements prior to full rate production.

Mission — Ops Control Center HLD source

Efforts funded in this PE focus on development, testing, and fielding, of a long-range early detection capability for airborne and surface targets of interest. Each line of effort acquires and fields a land based, high-frequency (HF) ionospheric backscatter radar for over the horizon detection and tracking of airborne and surface targets over wide geographic areas. Fielding of this capability will enable detection, tracking and reporting of airborne and surface targets that may be obscured from conventional line of sight radar systems by the curvature of the earth. HLD-OTHR efforts are focused on the development, testing, and fielding of capabilities to extend current NWS surveillance of long-range early warning for North America in response to emerging threats. The system was to be comprised of two OTHR systems and an Operational Control Center. HLD-OTHR data will be distributed and integrated into existing air, missile and maritime defense early warning networks, as applicable. This project will continue to focus investments to enhance capability for the Air and Cruise Missile Defense of the Homeland mission. The programs intent is to design, develop, test and field advanced OTHR systems operating at levels of sensitivity that exceed current US OTHR systems in operation. Program activities include C2 interface design and integration, HF sensor and digital receiver technology advancement, ionospheric characterization research, remote sensor management capability development, and sensor data fusion research. HLD-OTHR data was to be distributed and integrated into existing integrated air and missile defense (IAMD) early warning networks, to include the emerging DAF Battle Network and Cloud Based C2 architectures as applicable. In support of the Air and Cruise Missile Defense of the Homeland mission and NORAD/USNORTHCOM Defense of North America mission, the project will continue to focus investments to enhance capability for Over-the-Horizon Radars. HLD OTHR will continue executing experimental efforts with the DoD science and technology community to characterize ionospheric conditions in the CONUS. This program element may include necessary civilian pay expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in PE 0605827F, 0605828F, 0605829F, 0605831F, 0605832F, 0605833F, 0605898F, 0606398F This program is in Budget Activity 5, System Development and Demonstration (SDD) because it has passed Milestone B approval and is conducting engineering and manufacturing development tasks aimed at meeting validated requirements prior to full rate production.

Mission — TACMOR Development source

TACMOR capability is being developed for employment in the Republic of Palau to provide enhanced Air Domain Awareness in the USINDOPACOM area of responsibility. TACMOR will be operated by the United States and located in the Republic of Palau, with the agreement of the government of Palau. Development, test and evaluation, and acquisition of the system and associated components will provide warfighters with the capability to close gaps in surveillance coverage in key regions of the Pacific area of interest to the United States and our Allies. TACMOR radar system development, integration and test activities have been delayed from FY22 - 24 but the DAF has been able to. TACMOR efforts funded in this Program Element will include but are not limited to: A Transmit site consisting of fourteen elements and high-power amplifiers transmitting High Frequency [HF] Skywave Over-The-Horizon Radar [OTHR] waveforms. The transmit site will also consists of a HF vertical sounder antenna and a HF backscatter sounder providing ionosphere environmental information for optimizing frequency selection. Also includes a Receive site consisting of 128 dual-monopole antenna elements receiving the over-the-horizon reflected energy from the transmit site. The receive site also contains the secure facilities for signal processing of the received data and real-time target extraction information. This effort will also fund the communications infrastructure necessary to enable the data flow from the Transmit and Receive sites to an off-site operations control center. The operations control center plans and executes missions in support of the Combatant Command [CCMD] and provides real-time, target tracking information to all- source information fusion and dissemination systems. TACMOR data will also be accessible to and exploited by the National Air and Space Intelligence Center [NASIC] for detailed, post-event analysis. This program element may include necessary civilian pay expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in program element 0605827F, 0605828F, 0605829F, 0605831F, 0605832F, 0605833F, 0605898F, 0606398F. In FY2024 0 was expended for civilian pay expenses in this program element, and in FY2025 0 is forecasted for civilian pay expenses in this program element.

Mission — TALON TACMOR development source

TACMOR capability is being developed for employment in the Republic of Palau (RoP) to provide enhanced Air Domain Awareness in the USINDOPACOM area of responsibility. TACMOR will be located in the RoP and operated by the United States in agreement with the RoP. Development, test and evaluation, and acquisition of the system and associated components will provide warfighters with the capability to close gaps in surveillance coverage in key regions of the Pacific area of interest to the United States and its Allies. TACMOR efforts funded in this Program Element will include but are not limited to: An unmanned, remotely controlled, secure facility consisting of a Transmit site consisting of fourteen elements and high-power amplifiers transmitting High Frequency [HF] Skywave Over-The-Horizon Radar [OTHR] waveforms. The transmit site will also consists of a HF vertical sounder antenna and a HF backscatter sounder providing ionosphere environmental information for optimizing frequency selection. It also includes a Receive site consisting of 128 dual-monopole antenna elements receiving the over-the-horizon reflected energy from the transmit site. The receive site also contains the secure facilities for signal processing of the received data and real-time target extraction information. This data will enhance INDOPACOM and PACAF forces' Air Domain Awareness missions. This effort will also fund the communications infrastructure necessary to enable the data flow from the Transmit and Receive sites to an off-site operations control center. The operations control center plans and executes missions in support of the Combatant Command [CCMD] and provides real-time, target tracking information to all-source information fusion and dissemination systems. This program element may include necessary civilian pay expenses required to manage, execute, and deliver weapon system capability. The use of such program funds would be in addition to the civilian pay expenses budgeted in program element 0605827F, 0605828F, 0605829F, 0605831F, 0605832F, 0605833F, 0605898F, 0606398F. In FY 2024 0 was expended for civilian pay expenses in this program element, and in FY 2025 0 is forecasted for civilian pay expenses in this program element.

Accomplishments & Planned Programs (4)