WASHINGTON ― President Donald Trump’s nominee to be secretary of the Air Force has become mired in a conflict-of-interest controversy, raising the possibility that he will fail to secure any of his first three picks to run the three military departments.

Heather Wilson, the Air Force nominee, is combating accusations that she has disqualifying problems because of her relationship with the defense company Lockheed Martin Corp. Vincent Viola, Trump’s choices to run the Army and the Navy withdrew from consideration last month, saying they were unable to comply with government ethics requirements.

Wilson, a former congresswoman from New Mexico, began serving as an adviser to Sandia Corp., a Lockheed subsidiary, and other defense contractors immediately after she left office in 2009. As Air Force secretary, she would play a central role in Trump’s plans to reassess the development of Lockheed’s costly F-35 fighter jet and expand the U.S. nuclear arsenal, which includes Lockheed missiles, according to a Politico investigation into her conflicts.

“She has what I call the appearance of a conflict of interest, and appearances matter,” Gordon Adams, a former Office of Management and Budget official, told Politico. “She should probably recuse herself from anything involving Lockheed. That’s tricky — in particular for the F-35 ― because it’s a big part of the job.”

The Project on Government Oversight has called Wilson “a textbook example of the revolving door” between high government office and government contractors, urging close scrutiny from senators who will vote on her confirmation.

Wilson’s work was implicated in Energy Department inspector general inquiries into Lockheed’s lobbying in 2013 and 2014, but the watchdog found no fault with her conduct.

Wilson has responded to questions about her Lockheed work by saying she was not a lobbyist. Powerful Republicans still support her nomination.

But the drumbeat continues. In a Daily Caller column published Monday, Wes Martin, a retired Army colonel, demanded that Trump withdraw Wilson’s nomination.

“It is beyond logic for President Trump to believe Heather Wilson possesses the judgment and integrity to lead the Department of the Air Force further into the 21st Century,” wrote Martin, himself a former Sandia employee who described himself as a whistleblower. “The Secretary of the Air Force should exemplify the highest level of ethics, not be a living testimonial of personal interest over national security.”

LGBTQ advocates also have challenged Trump’s choice of Wilson, noting that she received a score of zero from the Human Rights Campaign during her time in Congress, and opposed efforts to fight discrimination. Under President Barack Obama, the U.S. military made historic strides toward incorporating and protecting LGBTQ service members. Leaders like Wilson could change course.

Trump’s Pentagon has struggled with staffing issues. No senior jobs other than defense secretary have been filled, The Wall Street Journal reported Tuesday. And the White House has pushed back against Defense Secretary Jim Mattis, who Congress and the foreign policy world had hoped would be a powerful force for moderation, most recently by opposing his choice to be the Pentagon’s top policy adviser.