The Critical Design Review of the CERP program paves the way for the modification of two B-52 bombers with the new engines, with work on the first bomber starting later this year.
The U.S. Air Force has announced that the B-52 Stratofortress bomber’s Commercial Engine Replacement Program (CERP) has passed the Critical Design Review (CDR). Following this milestone, the service says it can start the modifications to replace the old TF33 engines with the new F130 engines on two bombers.
The CERP’s CDR comes just over a year after the F130 completed its own CDR in December 2024. with the final designs validated through review of analyses, simulations, schematics, software code, and test results. Recently, Rolls Royce completed altitude and operability testing for the F130 engine at the U.S. Air Force Arnold Engineering Development Complex (AEDC) in Tullahoma, Tennessee.
The B-52 Commercial Engine Replacement Program held its Critical Design Review. This milestone enables the program to move closer to modernization of #B52 aircraft with fuel-efficient engines and advanced systems into the 2050s.
Learn more: https://t.co/VdjdDLZXI1 pic.twitter.com/xHwp0OtuG7
— Boeing Defense (@BoeingDefense) May 4, 2026
“This CERP critical design review is the culmination of an enormous amount of engineering and integration work from Boeing, Rolls Royce, and the Air Force that will enable the B-52J to remain in the fight for future generations,” said Lt. Col. Tim Cleaver, Bombers Directorate CERP Program Manager.
During the CDR’s comprehensive technical assessment, experts from the Air Force, Boeing, and Rolls-Royce scrutinized the complete system design to ensure it meets all requirements before major modification work begins. Cleaver described the CDR as a pivotal moment, as it now allows the program to rapidly move toward aircraft modification.
The work on the first bomber is scheduled to begin later this year. The Air Force says Boeing will modify the first two B-52H aircraft into the B-52J configuration with the new engines at its facility in San Antonio, Texas.
The two modified B-52J aircraft will undergo extensive testing at Edwards AFB, California, allowing to validate the new engines and related systems. Once testing is complete, the program will move toward modifying the remainder of the B-52H fleet.
B-52J and CERP
As we have often reported here at The Aviationist, the bomber’s current Pratt & Whitney TF33-PW-103s, used since the 1960s, will no longer be supportable beyond 2030. Because of this, the B-52 Commercial Engine Replacement Program (CERP) was kicked off in 2018, with GE Aviation, Pratt & Whitney and Rolls-Royce competing for the contract.
The winning offer from Rolls-Royce is the F130, the military version of the BR725 engine used by the Gulfstream G650 business jet and already powering both the C-37 and E-11 BACN in service with the U.S. Air Force. In 2023, two years after the selection in 2021, Rolls-Royce announced it launched F130 engine testing.
As happened with the B-52G, when new engines were the main reason the B-52G was redesignated as B-52H in 1962, with the new F130 engines, the Stratofortress will be given the designation B-52J. Another critical component of the B-52J upgrade is the Radar Modernization Program, with the first modified aircraft currently undergoing testing at Edwards AFB.
The Air Force planned to finalize integration activities and deliver the first lot of B-52Js in the 2026-2027 timeframe, with initial operational capability initially expected in 2030 but later delayed to 2033. The new engines will increase the bomber’s fuel efficiency, increase range, reduce emissions in unburned hydrocarbons, and significantly reduce maintenance costs.
While their overall shape is still the same, the new nacelles of the F130 engine are bigger than the original ones, while the new struts are shorter and get the nacelles closer to the wing. The wind tunnel testing on these was completed in 2022.
The new nacelles will be supplied by Spirit AeroSystems, which was awarded a contract from Boeing in 2023 to provide both struts and nacelles for the CERP program. The company, one of the world’s largest suppliers of struts and nacelles, has meanwhile been acquired by Boeing.
In December 2025, Boeing has been awarded a $2.04 billion task order for the Post-Critical Design Review (CDR) phase of the CERP. This will see Boeing completing system integration work, modification and testing of two B-52 aircraft with the new engines and associated subsystems by May 2033.
