High Frequency Radio Systems

The High Frequency Radio Systems program, identified as Program Element (PE) 0303133F in the Air Force RDT&E budget, focuses on the research, development, and operational systems integration of advanced airborne high frequency (HF) radio capabilities. The primary goal is to modernize long-range HF communications across 15 critical U.S. military aircraft platforms by replacing obsolete radios with new digital, software-defined HF radios. This modernization is essential to comply with Federal Aviation Administration (FAA) mandates for HF radio capability on transoceanic flights and to ensure operational readiness in scenarios where satellite communications may be unavailable or disrupted.

The Airborne High Frequency Radio Modernization (AHFRM) program is the central initiative under this line item. It addresses a capability gap that will emerge as legacy radios, which are no longer in production, fall below supply chain thresholds by mid-FY 2027. The AHFRM program impacts approximately 1,300 aircraft across the Air Force, Marine Corps, and Coast Guard, including platforms such as the AC-130J, B-1, B-52, C-5, C-17, C-130 variants, E-4C, KC-46, KC-135, and others. The new digital radio is the only airborne HF radio currently in development that can meet the technical and operational requirements for these platforms, providing enhanced survivability and secure communications for critical Force Direction messages.

A key objective for FY 2026 is the development of a digital antenna coupler for the new radio. The legacy analog coupler, inherited from previous systems, limits the radio's processing power to 10 kHz, well below the desired wideband throughput. The analog coupler's compatibility with the new radio is diminishing, as it is no longer in production and presents supportability challenges starting in FY 2027. The digital coupler will unlock the full capabilities of the new radio, supporting advanced features such as Automatic Link Establishment and Low Probability of Intercept/Detection/Geolocation, while also enabling future technology integration through an open architecture.

The Systems Engineering & Integration line supports the technical maturation and risk reduction activities necessary for the digital coupler's development. FY 2026 activities include vendor site visits to determine eligibility, vendor source selection, risk assessment and cost analysis, systems engineering trade studies, requirements refinement and validation, and prototyping. These efforts are managed by the Air Force Life Cycle Management Center at Warner Robins Air Force Base, Georgia, which provides contracting, legal, programmatic, engineering, test, and logistics support for the program.

In addition to product development, the program includes sustainment planning and integration operational testing for the new radio across all affected aircraft platforms. These activities ensure that the new radio system is properly integrated, tested, and supported for long-term operational use. The program also funds necessary civilian pay expenses required to manage and execute weapon system capability, supplementing other program elements as needed.

The acquisition strategy for AHFRM began as a Middle Tier of Acquisition Rapid Prototyping effort and transitioned to a Major Capability Acquisition ACAT III program in April 2024. The program has completed competitive rapid prototyping and awarded the development contract to BAE Systems. The Milestone Decision Authority is the Combat Avionics Division Senior Material Leader at the Air Force Life Cycle Management Center. The FY 2026 budget request reflects an increase in funding to support the digital coupler's development, offset by reductions in Advisory and Assistance Services to promote efficiency in line with Executive Order 14222.