Investigators have recovered the flight recorders—also known as black boxes—from both the commercial jet and the military helicopter involved in the mid-air collision near Reagan National Airport in Washington,

The black boxes are the nickname for the flight data recorder and cockpit voice recorder that record events during a flight.

Crews working at the site of the deadliest aviation disaster in a generation have recovered all 67 victims of the collision between two aircraft over the Potomac River in Washington, DC, officials said Tuesday.