Air Force Materiel Command’s KC-Y program has outlined a number of challenges for commercial derivative aircraft (CDA), such as the Boeing [BA] KC-46A Pegasus tanker, as the U.S. Air Force (USAF) contemplates whether to move forward on a KC-Y “bridge tanker” program.

“Primary depot support challenges surround unscheduled maintenance and unplanned parts supportability discovered during schedule letter checks,” the program said on July 13 in a response to questions from an unidentified contractor. “Additionally, parts tracking once they are in supply has been problematic, as well as engineering disposition challenges for repairs outside of task orders. Lastly, excessive and repetitive inspections to meet FAA [Federal Aviation Administration] requirements based on commercial flying program versus USAF flying hour program has been a challenge.”

“Letter checks” are scheduled maintenance with A and B checks falling under light maintenance, while C and D checks fall under heavy maintenance.

The Air Force has been examining whether to go forward on a program to buy 140-160 KC-Ys CDA tankers to fill the gap between the final delivery of the 179th KC-46A in 2029 and the future KC-Z tanker.

The KC-46A fleet and possible future tankers would replace more than 400 Boeing KC-135s and KC-10s in the coming decades.

Lockheed Martin [LMT] has been gearing up for a KC-Y competition and, in January, said that the company plans to build the LMXT refueler, based on the Airbus A330, in Mobile, Ala., and Marietta, Ga. (Defense Daily, Jan. 31).

The baseline for KC-Y may be the KC-X requirements, which resulted in the KC-46A award to Boeing.

Asked by the unspecified contractor for a summary of the KC-X sustainment solution, the KC-Y program replied on July 15 that “KC-X leveraged CDA, has and continues to utilize meet-the-intent (MTI) for FAA repair station certification, is in the process of migrating select parts for organic supply chain management, embraces public-private partnerships with vendors to advance Title 10 core and 50/50 compliance, and invests in software OS [operating system] to gather and analyze fleet logistics and sustainment data.”

Sustainment for the KC-46A features field and depot maintenance and letter check intervals under FAA MTI repair certification. While the Air Force provides maintenance with contractor support, supply chain management for some parts is to move from the contractor to the Air Force.

Air Force Secretary Frank Kendall told the Senate Armed Services Committee on May 3 that “as we looked at the requirements, it doesn’t look as necessary or as cost effective as it once did to introduce another aircraft as KC-Y.”

Nevertheless, the KC-Y program office is continuing its work, should the Air Force decide to move forward on KC-Y.

In the July 15 response to contractor questions on digital support for sustainment of the tanker fleet, the KC-Y program office said that the AFMC Mobility and Training Aircraft (MATAC) directorate’s digital architect “is currently instituting a MATAC digital enterprise strategy for its entire aircraft portfolio, which includes both KC-46 and KC-Y.”

“This MATAC digital enterprise strategy is an integrated digital approach encompassing all functional disciplines in order to support lifecycle activities and processes,” per the KC-Y program office. “It includes utilizing all Air Force digital enterprise tools to support the MATAC airlift, tanker and trainer fleets of aircraft and accelerate change. The baseline digital tools are CAMEO (model based systems engineering tool); TEAMCENTER (product lifecycle management tool; CLOUD ONE (cloud platform tool); CONFLUENCE, JIRA, BITBUCKET (agile software tools)
Exceptions to any of these tools require a waiver.”

The House’s version of the fiscal 2023 defense authorization bill would allow the Air Force to buy KC-Y without an open competition but would require the Air Force secretary to explain such a decision (Defense Daily, June 23).