WASHINGTON — The Air Force will know in June whether the KC-46 tanker program will be set back by another round of schedule delays, a service official told lawmakers Thursday.

KC-46A manufacturer Boeing is conducting a schedule risk assessment for the program and will update the Air Force's top acquisition officials — Darlene Costello and Lt. Gen. Arnold Bunch — during the first week of June, Bunch said during a House Armed Services subcommittee panel.

Bunch told reporters afterward he was concerned about schedule risk to several key dates in the test schedule, including the required assets available deadline in October 2018 that compels Boeing to deliver the first 18 tankers and nine aerial refueling pods. The company is already about one year behind schedule, having originally planned to meet the RAA milestone in August 2017 before technical issues pushed that date into late 2018.

"Boeing's design of several subsystems and production of conformed hardware are still pending FAA  [Federal Aviation Administration] approval, which is slowing flight test execution," Bunch wrote in testimony to Congress. "The test program is also running behind planned pace because several test aircraft are undergoing upgrades to incorporate design changes. Boeing is several months behind schedule, which means the first aircraft will likely to deliver after 12 September 2017."

In March, the Government Accountability Office noted the program was in danger of further delays, citing a packed testing schedule that leaves no margin for redoing test points.

Starting in September, Boeing will have to deliver about three aircraft a month to meet the current RAA date — a higher rate than is expected even in full rate production, the GAO stated. At the time of the report’s release, 12 aircraft were about 70 percent compete, but a tough test schedule still lies ahead.

According to the GAO, Boeing must execute 1,713 test points per month to be able to deliver the first aircraft in September, but its average completion rate is only about 800 points per month, according to data from March 2016 to January 2017. It has exceeded that 1,713 point goalpost only one time, in October 2016 when it completed 2,240 test points.

Despite difficulties keeping the program on schedule, Air Force investment remains steady, as the service still intends to buy 179 KC-46As by fiscal year 2028. In the FY18 budget request, the service called for $93.8 million to continue the engineering, manufacturing and development (EMD) phase and $2.6 billion to award Boeing a contract for 15 tankers in January 2018.

Bunch’s testimony acknowledged that the 179 KC-46As will replace less than half of the service’s current fleet of KC-10s and KC-135s. Therefore, further modernization of the KC-135 and "sufficient funding" of the two follow-on efforts to the KC-46 program — called KC-Y and KC-Z — will be necessary to meet Air Force requirements, he said.

Valerie Insinna is Defense News' air warfare reporter. She previously worked the Navy/congressional beats for Defense Daily, which followed almost three years as a staff writer for National Defense Magazine. Prior to that, she worked as an editorial assistant for the Tokyo Shimbun’s Washington bureau.

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