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,

U.S. commercial pilot Rick Redfern was preparing to land at Reagan Washington National Airport about a decade ago when he spotted a bright red Coast Guard helicopter hovering about 50 feet (15 m) above the Potomac River.

The crash disrupted flights at Reagan National Airport. Several dozen emergency crews could be seen at the scene of the crash, apparently just south of Reagan National Airport’s upper departure area,

When aircraft volume goes down, a supervisor can make the decision to combine two controller positions into one position, which happens routinely, according to a source with direct knowledge.

The National Transportation Safety Board has begun an investigation into the deadly mid-air collision between an American Eagle regional jet and a military helicopter that left all 67 people onboard the aircrafts dead.