The U.S. Army helicopter that collided with an passenger jet near Washington, D.C., had an advanced surveillance system turned off.

Salvage crews worked on the Potomac River on Thursday morning and could be seen pulling out pieces of the Army Black Hawk helicopter that crashed with a plane last week, killing everyone on board both aircraft.

WASHINGTON, D.C. (7News) — Recovery crews used a massive crane Monday morning to lift wreckage from the Potomac River, days after a tragic midair collision between a plane and a helicopter left dozens dead.