There were no survivors after an American Airlines regional jet with 64 people aboard collided with a Black Hawk military helicopter moments before the airplane was set to land at Washington, D.C.'s Ronald Reagan Washington National Airport on Wednesday night, officials said. The accident was the worst air disaster in the U.S. since 2001.

While landing at Ronald Reagan Washington National Airport in Washington, D.C., on Wednesday shortly before 9 p.m., American Airlines Flight 5342 collided with an Army Black Hawk helicopter and crashed into the icy Potomac River.

Captain Chesley Sullenberger, who famously landed a passenger plane on New York's Hudson River in 2009, has revealed his theory of what happened yesterday.