The last major collision of a commercial U.S. airline dates back to 2009, when a Colgan Air incident left 50 dead near Buffalo, New York. Federal regulators tightened safety requirements following the crash, including bolstering aircraft carrier inspection requirements and pilot training hours.

No survivors are expected after an American Airlines passenger flight collided midair with a U.S. Army Black Hawk helicopter late Wednesday night near Washington D.C.'s Reagan National Airport. The big picture: While the cause of the crash remains unknown,

Multiple fatalities were reported as an American Airlines passenger flight and an Army Black Hawk helicopter collided midair last night at the DCA airport in Washington D.C.