Air traffic controllers warned a US Army helicopter that it was getting dangerously close to an American Airlines passenger plane that was landing at Ronald Reagan Washington National Airport before the deadly collision on Wednesday night,

The tragic, midair collision in Washington, D.C. is putting a spotlight on air traffic controller shortages. It's a nationwide problem, but the area around NYC is especially hard hit.

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.