RC-135

The LI DARP01 - RC-135 line item in the Department of Defense (DoD) budget supports the Air Force's ongoing efforts to sustain, modernize, and upgrade its fleet of RC-135 reconnaissance aircraft. This program encompasses several mission-specific variants, including the RC-135V/W RIVET JOINT, RC-135S COBRA BALL, RC-135U COMBAT SENT, and WC-135R CONSTANT PHOENIX, all of which perform critical intelligence, surveillance, and reconnaissance (ISR) missions under the direction of Air Combat Command (ACC). The primary objective of this line item is to ensure these aging but essential aircraft remain viable, reliable, and technologically relevant through at least 2050, despite their average airframe age exceeding 57 years.

The RC-135V/W RIVET JOINT component comprises seventeen aircraft that form the backbone of the Air Force's manned reconnaissance capability. The FY26 budget focuses on initiating integration and testing of Baseline 15, continuing conversion of Baseline 12 aircraft to Baseline 14, and starting conversion of Baseline 13 aircraft to Baseline 15. These upgrades include scalable processor improvements, Wideband Agile Receiver and Pulse Detector (WARPD), expanded steered beam capability, augmented remote maintenance, and integration of StarShield for enhanced communications. The objective is to maintain ISR collection parity in a rapidly evolving threat environment and ensure interoperability with ground systems and training assets.

RC-135S COBRA BALL consists of three aircraft tasked with collecting foreign instrumentation signals intelligence (FISINT). FY26 funding supports integration and testing of Baseline 14 enhancements and procurement of long-lead items for Baseline 15. Upgrades include advanced direction finding antennas, high-gain steerable-beam K-band collection antennas, digital data recording, improved signal identification and classification, and integration of the RIVET JOINT Baseline 14 communications intelligence suite. The goal is to keep pace with adversary weapons system developments and maintain collection effectiveness through incremental, spiral upgrades.

RC-135U COMBAT SENT involves two aircraft focused on technical intelligence collection against adversary radar and electronic systems. FY26 procurement completes the conversion of Baseline 5 aircraft to Baseline 6, which features wideband collection, improved scientific and technical processors, enhanced antennas, upgraded operator interfaces, and sensor calibration systems. The program will also begin procurement of long-lead items for Baseline 7, ensuring continued capability improvements in dense signal environments and integration of communications intelligence upgrades derived from the RIVET JOINT program.

WC-135R CONSTANT PHOENIX is a specialized aircraft used for atmospheric collection and nuclear treaty verification missions. The FY26 budget includes funding for continued capability improvements to ensure mission effectiveness and survivability in evolving operational environments. These modifications are aligned with the overarching baseline integration strategy that governs the entire RC-135 fleet, leveraging synergies across variants for cost and schedule efficiency.

A key management approach across all RC-135 variants is the incremental baseline upgrade strategy, overseen by the 645th Aeronautical Systems Group (645 AESG). This strategy involves contracting for long-lead items in advance and synchronizing aircraft and ground system upgrades to maintain operational readiness and training alignment. The program manager is authorized to redirect funding as needed to address emerging Combatant Commander and Intelligence Community requirements, reflecting the dynamic nature of global threats and technological advancements.