A Boeing KC-46A Pegasus tanker with the US Air Force (USAF) suffered an emergency during a refuelling flight over California that reportedly resulted in significant damage to the jet’s fuel-transfer boom.

The aircraft is assigned to the 22nd Aerial Refueling Wing at McConnell AFB in Kansas, but on 21 August was operating over Santa Barbara, California – where President Joe Biden is currently on holiday.

The pilots “declared an in-flight emergency in relation to the aircraft’s boom equipment”, the USAF tells FlightGlobal.

The jet apparently was operating with call sign “Wide 12”, according to publicly available air-traffic control recordings.

F-15 refuelling in flight

Source: Travis Air Force Base

The KC-46 was reportedly refuelling an F-15E fighter when the emergency occurred, although the USAF has not confirmed any details

Flight tracking site Flightradar24.com shows multiple USAF tankers in the area throughout the day bearing call signs with the “Wide” prefix. Air-traffic-control audio posted to social media captured the pilot of Wide 12 declaring an emergency with “hydraulic failure”.

The pilot subsequently requests firefighting support on the ground at Travis AFB, where the KC-46A diverted. Travis is near San Francisco and some 260nm (482km) north of Santa Barbara.

The USAF confirms the KC-46 crew landed safely at Travis.

While the service does not disclose the nature of the mission, the sortie many have been related to Biden’s presence in the area. Air & Space Forces Magazine, a publication of the USAF-affiliated Air & Space Forces Association, reports that the KC-46 suffered the problem while refuelling a Boeing F-15E fighter.

Unverified photos posted to Facebook on 21 August appear to show a heavily damaged KC-46 on the ground, with a severed refuelling boom and crumpled tail section. The images have not been verified by the USAF.

Air-traffic control audio from the day appears to corroborate that possibility.

“We were relayed info that their boom fell off,” the pilot of an aircraft with the call sign Noble 41 tells controllers about the status of the tanker.

The USAF says the incident is under investigation.