WASHINGTON — The Air Force secretary expects the KC-46A tanker to have its first flight sometime over the summer, a "several month" delay for a milestone on the program.

The timeline laid out for Defense News by Air Force Secretary Deborah Lee James clarifies provides clarity to comments made Tuesday by Brig. Gen. Duke Richardson, program executive officer for tankers, that the tanker was going to miss the expected first flight date of mid-April.

"It is concerning me," James said in a Thursday interview. "My best belief, at this point, is it will be a several-month delay. So hopefully summertime is when it would occur."

This is not the first delay of a major test point on the tanker. The first test flight of a Boeing 767-2C, a test version of the KC-46A without the refueling boom and other tanker equipment, had originally been was scheduled for June of 2014; it eventually occurred just before the New Year.

Executives for Boeing have emphasized in the past that its focus is on a contractual obligation to provide 18 ready-to-go tankers on the ramp by 2017, and noted that first flight dates are targets, not obligations.

James did say note that the KC-46 program has some good news, noting that the costs are capped and the company is largely on track for its major contractual requirements.

However, Richardson warned on Tuesday that the margin built into the schedule was essentially gone, and that any delay in getting that first flight up was a concern because of the need to get air worthiness certifications.

James echoed Richardson's concern about the lack of margin, and added that Boeing has submitted a new integrated master schedule, laying out its internal target dates, for review by the Air Force. She added that timeline is under review.

"The worrying news is that underneath those contractual and milestone requirements, there are a whole lot of other milestones," James said. "This is the internal plan for how do you get from here to there to meet the milestones. That's where there have been challenges and slippages and so forth, so that is the worrying part."

The KC-46A will replace the majority of the service's current tanker fleet with 179 new planes, based on a Boeing commercial design.

Email: amehta@defensenews.com

Aaron Mehta was deputy editor and senior Pentagon correspondent for Defense News, covering policy, strategy and acquisition at the highest levels of the Defense Department and its international partners.

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