According to Sky News, the pilot reported that an object had struck the Airbus A320 as it arrived at the London hub from Geneva. The flight, BA727, landed safely at Heathrow's Terminal 5.
British Airways said the aircraft was checked by engineers and cleared and cleared to make its next scheduled flight. Sky News reported that London's Metropolitan Police were investigating the incident and no arrests had been made.
The strike is the latest in a string of incidents involving drones and aircraft over British airspace. A report released last month recorded 23 near misses between drones and aircraft between April and October 2015.
Frankly it was only a matter of time before we had a drone strike given the huge numbers being flown around by amateurs who don't understand the risks and the rules," Steve Landells of the British Airline Pilots Association told Sky.
The UK Civil Aviation Authority's so-called "drone code" requires the unmanned craft to be kept away from planes and airports, and not be flown above 400 feet.