The vice president and transportation secretary claimed that diversity hiring efforts had affected staffing levels among air traffic controllers, but there is no evidence that such efforts played a role in the crash.

The transportation secretary, Sean Duffy, said the Federal Aviation Administration had used a backup system while it addressed the problem.

In a briefing that recalled his most extreme first term remarks, President Trump said without any evidence that diversity initiatives caused the midair collision.

President-elect Donald J. Trump has leaned heavily on familiar faces from the cable network as he fills out his second-term cast.

Sean Duffy, a former Fox Business host and Wisconsin congressman, would oversee a sprawling Transportation Department that oversees aviation, rail and transit.

Selections for attorney general, secretary of homeland security, secretary of state and Treasury secretary are among those set to have hearings this week.

President-elect Donald Trump’s chief advisers would include one person who calls global warming an “existential” threat and some who don’t accept it as a problem at all.

© Pool photo by Allison Robbert; Carlos Barria/Reuters; Patrick T. Fallon/Agence France-Presse — Getty Images; Dominic Gwinn/Middle East Images/AFP via Getty Images