Following the departure of Deputy Secretary of State Ash Carter, President Obama has appointed Christine Fox to serve under Defense Secretary Chuck Hagel as the acting Deputy Defense Secretary. Fox, who previously served as the director of the department's Cost Assessment and Program Evaluation, will become the highest-ranking women to ever serve at the Defense Department.

"As a key leader of the Strategic Choices and Management Review, [Fox] helped identify the challenges, choices, and opportunities for reform facing the department during this period of unprecedented budget uncertainty," Hagel said in a statement released by the Pentagon.

According to Politico, Fox has been working in defense for decades, and was the inspiration for the fighter-pilot instructor in "Top Gun," the film's lead female role played by Kelly McGillis. A defense source told the news outlet that despite her vast experience, Fox does not want to be considered as a candidate for the permanent deputy defense secretary position. 

Former Deputy Defense Secretary Carter announced his resignation in October, but did not officially leave his post until Dec. 4. Fox will take over this week and serve until Carter's successor is appointed.