B-21 Spotted Flying with KC-135 in Precursor to Refueling Test

Aviation enthusiasts were treated to a historic sight March 10 over Edwards Air Force Base, Calif.—the Air Force’s new B-21 bomber flying alongside its veteran, Eisenhower-era KC-135 aerial tanker.

While the flight led to speculation that the B-21 has started aerial refueling tests, an Air Force spokesperson told Air & Space Forces Magazine that it was actually a “close-proximity flight,” meaning the B-21 never actually locked into the KC-135’s boom.

“We can confirm that a B-21 Raider completed a test event involving a close-proximity flight with a KC-135 Stratotanker,” the spokesperson said. “This flight is part of the ongoing, rigorous test campaign to validate the B-21’s capabilities and operational readiness.”

The aerodynamics of two aircraft flying close together are complicated, and proximity tests are likely a precursor to full-fledged refueling tests to come, though the Air Force declined to comment on that front.

“To maintain enhanced security measures, we will not provide further details on specific test points. The B-21 program remains on track to deliver a survivable, long-range, penetrating strike capability to the U.S. Air Force,” the spokesperson said.

Pictures of the tanker-bomber pairing quickly made the rounds on social media, with an F-16 chase plane also visible.

The KC-135 Stratotanker entered service in 1957 and is now expected to fly to 2050 or beyond, a remarkably long service life matched only by the bomber it was first acquired to refuel: the B-52 Stratofortress.

The B-21, meanwhile, is racing toward the start of its service life with the first bomber expected to be delivered to an operational base in 2027, the Air Force announced last month. The first Raider started flight testing out of Edwards in early 2024, and a second aircraft joined it in September 2025. Officials said at the time the second aircraft would allow them to start testing “weapons and mission systems,” as compared to just airworthiness and handling qualities with the first aircraft.

It is unclear which test aircraft was involved in the flight with the KC-135.

Here’s a few shots I snapped of the B-21 doing AR tests over California yesterday. Much more to come later pic.twitter.com/2yEWXsqyUU

— jmh.creates (@JarodMHamilton) March 11, 2026