Helicopters will be permanently restricted from flying near Washington, D.C.'s airport on the same route where a passenger jet and an Army helicopter collided in midair, killing 67 people, the Federal Aviation Administration said Friday.

The closure of the helicopter route near the airport makes permanent the restrictions put in place after Jan. 29 midair collision.

The closure comes after crash investigators said there was a history of safety risks near the busy airport that had gone unaddressed.