Last month, an American Airlines passenger jet and an Army helicopter collided as the plane prepared to land at Washington D.C.’s Ronald Reagan National Airport.

In the three years before the deadly collision between an Army helicopter and an American Airlines flight near Reagan National Airport, at least two other pilots reported near-misses with helicopters while landing at the airport,

The Army was one of 28 government agencies authorized to fly helicopters near Ronald Reagan National Airport before its Black Hawk helicopter collided with an American Airlines passenger jet last week,

On Jan. 29, an American Airlines passenger jet and an Army helicopter collided as the plane prepared to land at Washington D.C.’s Ronald Reagan National Airport.

LIVE: Watch the NTSB press conference in the video player above. The collision was the deadliest plane crash in the U.S. since 2001, when a jet slammed into a New York City neighborhood just after takeoff,