If changes aren't made, that near-miss becomes a mid-air collision,” one aviation safety expert said. “Unfortunately, that's what we had last night.”

An Army Black Hawk helicopter collided midair with an American Airlines flight from Wichita, Kansas, at Reagan National Airport on Wednesday.

Political leaders had warned about the dangers of Ronald Reagan Washington National Airport in Washington, D.C. months before an American Airlines flight collided with a U.S. Army Black Hawk helicopter on its approach to the airport.