The UK Airprox Board investigated a drone near-miss reported by Airbus A320 near London-Heathrow Airport on 15 March 2015. Separation distance reported as 50 feet.
THE A320 PILOT reports conducting a normal approach to RW09L at London Heathrow. At 4.5nm from the threshold, a black object appeared and was observed tracking in a westerly direction, up the approach path. The object passed about 50ft directly above the aircraft. ATC were informed. The pilot did not take avoiding action, and the approach was continued to a normal landing. The pilot stated that the object was rectangular in shape and appeared to be propeller driven, ‘like a drone’.
The Board considered the actions of the A320 pilot and noted that, with his aircraft configured for landing, he had had only a limited capability to take avoiding action had it been required. They also noted that the pilot had simply reported that the encounter had involved a non-specific drone-like or balloon-like object; Board members opined that it had probably been a combination of his closure speed and the startle factor of suddenly seeing something on his approach path that had contributed to his uncertainty. Some members felt that it may indeed have been a balloon, which the prevailing wind would have blown along the approach path, but others noted that he had later commented that it appeared to be propeller-driven and so this indicated to them that it was more possibly a small unmanned object. After much discussion, members agreed that, although there had clearly been something there, in this case there was simply too little information to make a reliable assessment of either what it was or the risk of collision. Nevertheless, it was clear that the A320 pilot had been concerned by its proximity and the consequent safety of his aircraft.
Aircraft: Airbus A320
Aircraft altitude: 1700 ft
Separation: 50 feet
Please note that separation distances are solely based on pilot’s judgements and not necessarily accurate since horizontal and vertical separation distances can be hard to judge.