A British Airways A320 was hit by what most likely was a drone as it prepared to land at London's Heathrow Airport on Sunday.
Police said the pilot of the BA flight from Geneva had reported that he believed a drone had struck the aircraft before it landed safely.
Britain's Air Accidents Investigation Branch confirmed on Monday that it had launched an investigation into an incident involving an unmanned air vehicle and a passenger aircraft at Heathrow, Europe's busiest airport.
The use of civil drones, whether for commercial purposes such as crop surveillance, monitoring of natural disasters, photography or just as a leisure activity, is rising.
That popularity has led to increasing reports of near-misses with commercial aircraft.
The European Commission has conceded that "drone accidents will happen", while the UK's Civil Aviation Authority last year issued a warning after seven incidents in less than a year where drones had flown near planes at different UK airports.
Pilots' associations and others have called for drones to be fitted with geo-fencing technology, which uses GPS software to stop them straying into certain areas, along with height and distance limits. They also call for registration of drones.
Commenting on the latest incident, the British Airlines Pilots Association said that more education for drone users and stronger enforcement of the rules around drones were needed to keep aircraft safe.
"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," BALPA flight safety specialist Stephen Landells said.
British Airways said in its statement that the aircraft, which had 132 passengers and five crew on board, was fully examined by engineers before being cleared to operate its next flight.
The incident was reported to police by the pilot after the flight landed at about 11:50 GMT on Sunday.
"It transpired that an object, believed to be a drone, had struck the front of the aircraft," the police said.
The incident on Sunday followed another at Heathrow in February, when a New York-bound plane was forced to return to the airport after a "laser beam incident".