The U.S. Air Force has completed the Critical Design Review for the B-52 Stratofortress Commercial Engine Replacement Program, clearing the path for modifications on the first two bombers. The review, conducted by experts from the Air Force, Boeing, and Rolls-Royce, verified that the design meets technical and operational requirements.
Under the program, the aging TF33 engines from the 1960s will be replaced with Rolls-Royce F130 turbofans, along with new generators and subsystems. Boeing will perform the work at its San Antonio, Texas facility, starting with the first B-52 later this year, followed by a second aircraft. The modified B-52J bombers will then undergo flight testing at Edwards Air Force Base in California.
The upgrades aim to improve fuel efficiency, extend range, cut emissions, and lower maintenance costs across the fleet of 76 operational B-52H aircraft. In December 2025, Boeing received a $2.04 billion task order to handle post-review integration, modifications, and testing of the two aircraft by May 2033. Initial operational capability is now projected for 2033, delayed from earlier targets. The Air Force requested $998 million for the program in fiscal 2027 to support development and hardware.
The Critical Design Review, originally planned for 2023, faced delays and cost increases, with total program estimates rising to around $9 billion by 2024 reports.