Donald Trump isn’t his commander-in-chief quite yet, so on Monday the U.S. Air Force general in charge of the troubled F-35 Joint Strike Fighter program pushed back against the president-elect’s comments from last week describing production of the state-of-the-art plane.

Trump had attacked the program on Twitter, saying “The F-35 program and cost is out of control. Billions of dollars can and will be saved on military (and other) purchases after January 20th.” The tweet came less than a week after the incoming president attacked another major Air Force contract -- the deal with Boeing to upgrade the presidential plane, Air Force One.

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Speaking to reporters on Monday, Lt. Gen. Chris Bogdan said, “This program is not out of control.” He added, “I would like to explain to the new administration this is a vastly different program from 2011.”

Bogdan was referring to a time when many of the cost overruns with the program peaked. While the program still faces considerable criticism from within and without the Pentagon, Bogdan insisted that it has been dramatically reformed in recent years.

“Since 2011 we have basically been on schedule,” Bogdan said. “Since 2011 we have basically been on budget. We are delivering now today 50+ airplanes a year.”

He went on to predict that when the program is finally operating at capacity (only a relative handful of planes are currently being produced each year) that they are expected “to come down in price significantly … probably somewhere on the order of six to seven percent.”

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Bogdan said he was not upset that the incoming administration would be looking for efficiencies in the Defense Department’s procurement system.

“The new administration I believe is putting everyone on notice, not just industry but the Department that it wants better value from its dollar. I applaud the new administration for doing that.”

Also on Monday, Air Force Secretary Deborah Lee James spoke at a separate event in Washington and said that if Trump thinks he’ll be able to step in and immediately reduce the costs of the F-35 program, he might want to think again.

“It’s not quite as easy as it seems to get these costs down,” James said, a message she indicated her staff is currently trying to make clear to the Trump transition team.