Boeing notified operators in January 2023 that it had detected an issue with the paint primer used by a supplier in the central wing fuel tank of some KC-46A Pegasus and 767-300F aircraft.
According to The Air Current, which first reported on the issue, Boeing has not fulfilled aircraft deliveries to commercial operators over the past several months. The problem could also have consequences reaching far beyond the Boeing 767 family of aircraft.
Only three aircraft have been delivered between December 2022 and March 9, 2023, namely Manufacturer Serial Number (MSN) 63141, a 767F to FedEx (registered as N284FE), MSN 63140 also to FedEx (N285FE), and a KC-46 to the USAF, registered as 20-46073, per planespotters.net data.
Boeing’s Orders & Deliveries data showcased that two 767Fs were handed over to FedEx in December 2022, with no aircraft of the type delivered to customers in 2023, according to the manufacturer’s data up to January 31, 2023. In total, Boeing has 55 unfilled orders for the 767F.
Meanwhile, there are 13 MSNs that are slated for delivery, as shown by planespotters.net data. Out of these, only one flew recently, namely N283FE, a FedEx 767F. The wide-body freighter operated two flights in January 2023, departing and landing at Everett Paine Field (PAE) on January 8 and January 10, 2023. An Air Tanzania Boeing 767F was spotted with its livery painted at PAE.
The Air Tanzania Cargo 767 is now painted pic.twitter.com/1svLba9Zc7— Paine Airport (@mattcawby) March 9, 2023
“We will deliver airplanes as we complete rework and we are not changing our overall delivery plans for the year,” Boeing told Flight Global. “Our engineering analysis to date is that the issue is not an immediate safety of flight concern.”
AeroTime approached Boeing for comment.
Are USAF fighter jets at risk of grounding?
The Boeing KC-46A Pegasus is an aerial refueling and transport aircraft derived from the 767-2C commercial aircraft and is currently in service with the United States Air Force and the Japan Air Self-Defense Force. The Israel Air Force has four KC-46A tankers on contract to be delivered. To date, the USAF has ordered 128 KC-46A Pegasus.
“Initial assessment has not identified any immediate safety risk to the fleet,” an Air Mobility Command spokesperson told AeroTime in an email comment. “Full root cause analysis and corrective action are still in work.”
If an issue, such as the paint flaking and contaminating the fuel, was detected, it could have substantial consequences for the USAF. Indeed, the center wing tank is not only responsible for storing the fuel needed by the Pegasus, but also for distributing it to other aircraft.
Since the first KC-46A Pegasus tanker was delivered to the USAF in January 2019, the aircraft has been incrementally certified to refuel more and more aircraft operated by the country.
In October 2021, the KC-46A conducted its first “alert launch and response,” refueling fighters on their way to intercept and identify a potential air threat. In June 2022, Air Force Secretary Frank Kendall reported that the Pegasus was capable of servicing 97% of the US aircraft it was meant to refuel.
Thus, a fuel contamination issue with the Pegasus could potentially extend to other aircraft fleets. However, so far, the Air Mobility Command has not identified any issue.
“There have been no documented instances of fuel contamination caused by non-conforming tank primer on KC-46A aircraft,” according to the Air Mobility Command spokesperson. “As a result, there are no inspection requirements for refueling receiver aircraft.”
The Japan Air Self-Defense Force did not report any issue with the two KC-46As it has already received, out of the six on contract.
The Boeing aircraft has encountered numerous technical problems since its first delivery. After the United States Air Force discovered issues with the design of the KC-46A’s boom, operational refueling missions were temporarily restricted to the use of the aircraft’s centerline drogue system.