The Black Hawk helicopter that crashed into an American Airlines flight was alerted to the plane’s presence by air control twice, according to the reports.

Families and friends of those who lost loved ones in the deadly American Airlines and Army helicopter collision are sharing tributes online in memory of the crash victims.

In the deadliest U.S. major commercial aviation incident in 16 years, there were no survivors in a collision between a commercial aircraft and an Army helicopter by Ronald Reagan National Airport near Washington D.