Football-sized drone flown 20m from Heathrow-bound plane Published duration 9 December 2016

image copyright PA image caption Rules govern how drones can be operated in the UK

A drone the size of a football was flown within 20m (66ft) of a passenger jet as it approached Heathrow Airport, an investigation has found.

The Airbus A320 was above Biggin Hill, south-east London, when it narrowly avoided a collision with the unmanned craft, UK Airprox Board (UKAB) said.

Crew members saw the drone but would not have had sufficient time to take action.

Police have not been able to locate the drone operator, UKAB said.

The plane was flying at 11,000ft when the drone was spotted passing the right wing "very quickly" by the first officer on 4 August.

The dronecode

UK rules on flying drones, called the dronecode , were drawn up by the Civil Aviation Authority (CAA). It states drones should:

Be visible at all times

Be flown below 400ft (122m)

Not be flown over congested areas

The officer alerted the captain by shouting "look", the report said, but they did not have time to take evasive action.

They informed Air Traffic Control and were interviewed by Met Police officers about the near-miss once they landed.

image copyright Getty Images image caption The Airbus A320 had been waiting to land at Heathrow when it passed the drone

UKAB's board found the drone had "flown into conflict with the A320".

The report concluded the drone had endangered the lives of those on the plane as a collision "had only been narrowly avoided".

An Airbus A320 can typically carry up to 180 passengers.

A spokesperson for the CAA said it was "totally unacceptable to fly drones close to aircraft and airports" and "anyone flouting the rules can face severe penalties including up to five years in prison."

Figures have shown there were more reported near misses between drones and aircraft over the UK in the first six months of 2016 than during the whole of the previous year.

Sion Roberts, the head of drone training academy RUSTA, said the operator would have been flying "BVLOS (Beyond visual line of sight)" which was against regulations.

"These vehicles are easily bought from shops or online and often the people buying them don't know the rules and regulation or indeed the dangers involved", he said.

He added it was "vital distributors and sellers make their customers aware of the rules" or "one incident could put this growing industry back years."

Recent drone near-misses investigated by UKAB