Replacement B-52 test engine deliveries expected in 2027

AURORA, Colorado—Test engines meant to keep the B-52 Stratofortress in the skies through the bomber’s 100th birthday are expected to be delivered in 2027 after recent key performance evaluations, Rolls Royce confirmed to Defense One.

The upgraded F130 engines completed altitude and operability testing earlier this month at the Air Force’s Arnold Engineering Development Complex in Tennessee, the company said in an emailed statement. 

The planned replacement of aging Pratt & Whitney TF33-PW-103s is intended to keep the B-52s flying after the B-1 and B-2 bombers retire in the 2030s, when the upgraded Stratofortress and next-generation B-21s will be backbone of the service’s long-range strike missions.

Initial F130 flight test engine builds are underway “with delivery in 2027 to support the start of test aircraft modification,” Rolls Royce confirmed to Defense One.

As part of the multi-billion dollar Commercial Engine Replacement Program, or CERP, the company and the Air Force put the engines through tests simulating “long-duration, high-altitude strategic missions.” Boeing, which was awarded a $2 billion task order in December to outfit two of the bombers with the new test engines, also conducted electrical testing alongside Rolls Royce. After the engine and key avionics upgrades, the Air Force will designate the aircraft as the “B-52J” Stratofortress. 

“We are proud to deliver another milestone for our F130 engine testing program, on-time and on-budget, for the Air Force,” Jennifer Schwerin, a Rolls Royce program director, said in an emailed statement, adding that “our team has demonstrated the F130’s ability to meet mission requirements and further strengthened confidence that this engine is the right choice for the B-52J.”

A critical design review for the entire commercial engine replacement program is scheduled for this April, the Government Accountability Office said in its annual weapons report this past summer. 

The Air Force awarded Rolls Royce a $2.6 billion contract in 2021 for the engine overhaul.

The F130 replacement engines passed a Critical Design Review in late 2024. The program will conduct further dual-pod testing at NASA Stennis Space Center in Mississippi marking “another milestone in the propulsion development,” Rolls Royce said in a statement.

Other aspects of B-52 modernization efforts have been under intense scrutiny following F130 engine integration problems tied to Boeing and skyrocketing radar upgrade costs that triggered a breach of the Nunn-McCurdy Act last year.