A key safety system was turned off on the U.S. Army helicopter that collided with an American Airlines regional jet last week near Washington's Reagan Airport, killing 67.

The Army Black Hawk helicopter that collided with an American Airlines commuter plane near Reagan Washington National Airport in Virginia Wednesday was on a “training flight” when they crashed into the Potomac River, according to the military service branch.

The Army Black Hawk helicopter involved in the fatal midair collision in Washington, D.C., had a tracking system turned off, Sen. Ted Cruz said.