Sixty passengers and four crew members from the plane and three Black Hawk helicopter personnel are feared dead as a recovery mission is underway.

Black Hawk helicopter that collided with a jetliner on Wednesday night just off of Ronald Reagan Washington National Airport were all very experienced and not only had thousands of hours of flight time between them but were very familiar with the flight patterns above the Potomac River.

The helicopter involved in the fatal midair collision on Wednesday night may have flown off its approved path, The New York Times reports.