The B-52H will be redesignated the B-52J or possibly B-52K when it gets a new radar and new engines

Since some of the new APG-79B4 radars will be installed on the B-52 bombers before the new Rolls-Royce F130 engines, the question is whether there will be two designations.

When the B-52H gets a new radar and new engines it will be redesignated the B-52J or possibly B-52K, but the US Air Force (USAF) hasn’t yet decided what will constitute the new B-52 variant, according to Col. Louis Ruscetta, senior materiel leader for the program, Air Force Magazine reports.

The program has also developed a new estimate of what the re-engining will cost and is about to submit it to Congress, as directed under last year’s defense bill, but Ruscetta said reports of a 50 percent overrun are far overstated. In fact, he said he sees no overruns on the horizon.

Ruscetta told reporters at Air Force Materiel Command’s Life Cycle Industry Days conference in Dayton, Ohio that the radar and engine program represent “the largest modification in the history” of the B-52. According to Ruscetta, the change from B-52G to B-52H in 1961 was mainly the switch to the TF33 engine, but the new package includes radar, engines, communications, pylons, cockpit displays, and the deletion of one crew member station, meaning “it makes sense” to have a new designation.

Ruscetta explained that since some of the new APG-79B4 radars will be installed on the bombers before the new Rolls-Royce F130 engines, the question is whether there will be two designations. Ruscetta added that for the version with the new radar the B-52 pilot operating manual and maintenance manuals will be re-written; and will be re-written again when the engines are changed.

“What the Air Force, along with Global Strike Command, needs to look at, is how do we define” the new variant, Ruscetta said. The decision will be made sometime within the next two years, before installations begin.

As the USAF migrates toward the two-bomber fleet of B-21s and B-52s the new active, electronically scanned array radar as a “game changer” for the B-52, Ruscetta pointed out. He said that the APG-79 is effectively the same radar as on the export version of the Navy F/A-18 fighter, with the array turned “upside down” so it looks more down at the ground than up at the sky.

“We will have fighter-quality radar … to support air-to-ground operations,” he said, and be better able to operate “with other coalition partners” because the bomber will be able to use the same sensor format. It will be able to scan farther, “guide weapons in flight,” and improve the bomber’s situational awareness, he said. The B-52 today is still flying with its 1960s mechanical-scan radar.

Flight testing with the new radar will start in late 2025, and the first production versions should be built around the same time. They’ll be installed in early 2027, Ruscetta said, and initial operational capability (IOC) with the radar will consist of 12 aircraft as the required assets available for the declaration.

The first aircraft will be operational with the new engines circa 2030.

“It is more than just new engines,” he said. It’s “new pylons … generators … fuel lines … cockpit displays.” It is “a much bigger effort than just Rolls-Royce.” Boeing is the integrator of the all the B-52 upgrades.

The B-52 was America’s first long-range, swept-wing heavy bomber. It began as an intercontinental, high-altitude nuclear bomber, and its operational capabilities were adapted to meet changing defense needs.

B-52s have been modified for low-level flight, conventional bombing, extended-range flights and transport of improved defensive and offensive equipment — including ballistic and cruise missiles that can be launched hundreds of miles from their targets.

With each variant, the B-52 increased in range, power and capability. In all, 744 B-52s were produced by Seattle, Wash., and Wichita, Kan., plants between 1952 and 1962.

Throughout the 1950s, the B-52 chalked up many distance and speed records. It cut the round-the-world speed record in half, and in January 1962, flew 12,500 miles (20,117 kilometers) nonstop from Japan to Spain without refueling. This flight alone broke 11 distance and speed records.

Photo credit: Staff Sgt. Angelita M. Lawrence / U.S. Air Force