It is not clear whether the Army Apache helicopter collision with the Iranian drone was intentional, and official statements only said the crash is under investigation.
The air traffic controller who was managing numerous aircraft around Reagan National Airport felt a "little overwhelmed" just a few minutes before an American Airlines jet collided midair with an Army helicopter near Washington D.C., an investigator said.
The Orange County Fire Authority is not renewing its participation in a multi-county "quick-reaction force" program comprised of firefighting helicopters.
A private helicopter with four people on board crashed in mountains near Phoenix, Arizona on Friday, authorities said.
Two pilots were killed after their helicopters collided in midair over Hammonton, New Jersey on Sunday.
One person is dead and another is critically injured after two helicopters collided in Hammonton, New Jersey.