B-52 Stratofortress engine upgrade clears design milestone, moves toward flight testing

The U.S. Air Force’s B-52 Commercial Engine Replacement Program (CERP) has successfully completed its Critical Design Review (CDR), a key step that clears the way to begin physically upgrading aircraft to the new B-52J configuration.

Led by the Air Force Life Cycle Management Center with partners Boeing and Rolls-Royce, the programme will replace the bomber’s ageing 1960s-era TF33 engines with modern, fuel-efficient F130 engines. This upgrade is central to extending the operational life of the B-52 Stratofortress through at least 2050.

The CDR marks the transition from design to production, confirming that the system meets all technical and operational requirements. With the design now validated, Boeing will begin modifying two B-52H aircraft into B-52J variants at its San Antonio facility, with the first aircraft arriving later this year.

In addition to new engines, the upgrade includes improved subsystems such as enhanced electrical power generation to support future capabilities. After modification, the two aircraft will undergo extensive flight testing at Edwards Air Force Base before the upgrade is rolled out across the wider fleet.

Overall, the milestone reflects years of coordinated engineering work and positions the B-52 fleet for decades of continued service.