The collision involved a Bombardier CRJ700 regional jet operated by PSA Airlines and a military Black Hawk helicopter.
The former FAA head tussled with Musk and wanted to fine SpaceX for safety violations. He resigned after Trump won the election and hasn't been replaced.
Before Wednesday's crash between a passenger jet and an Army Black Hawk helicopter, the last fatal crash involving a U.S. commercial airline occurred in 2009 in New York.
American Eagle flight 5342 collided with a Black Hawk helicopter over the Potomac River, home to some of the country's most restricted airspace.