This is why we need FAA rules for drone flights. I can't even imagine what was going on in the cockpit when this happened.
An Airbus A320 capable of holding 180 passengers was approaching the runway at 700 feet during a landing when a helicopter drone suddenly appeared. The Civil Aviation Authority (CAA) has not released how close the drone came to the plane, or which airline it was.
But what we do know is that it was a mighty close call. The CAA rated the near-collision as an "A" incident, which is the highest rating possible and means "serious risk of collision."
The drone seemed to come out of nowhere. The Heathrow control tower was unable to notify the Airbus because the drone did not appear on the air traffic control radar and disappeared after the incident.