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.

Air-traffic control radar appears to have measured a US Army helicopter flying at a lower altitude than an American Airlines Group Inc. jet before the two collided near Washington, DC, on Wednesday, National Transportation Safety Board officials said.

The Army has released the name of the third soldier who died Wednesday when an Army helicopter collided with an American Airlines jet near the D

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,