A holiday jet carrying up to 189 passengers missed a suspect drone by just 6ft while coming in to land.
The close call by a Jet2 flight above Stansted is one of the narrowest near misses ever recorded in UK airspace.
A report revealed the shocked pilot told air traffic controllers that he “did not know how it did not hit the aircraft”.
Investigators found there was a serious risk of collision during the ‘Category A’ incident.
In his evidence the pilot said he was preparing to land “when suddenly a white object believed to be a drone appeared and narrowly avoided hitting the aircraft to the left-hand side of the nose cone.”
He added: “It managed to pass without hitting the aircraft.
“The whole event happened too quickly for any avoiding action to be taken.”
A team from the UK Airprox Board which investigates near misses said: “The Board considered that the pilot’s overall account of the incident portrayed a situation where providence had played a major part in the incident and/or a definite risk of collision had existed.”
The dramatic incident happened at a height of 2,700ft three miles north west of Harlow, Essex, in September this year.
The Boeing 737, believed to have been a Jet2 flight from Menorca, was making its final approach to London Stansted.
According to the report the passenger plane was travelling at 200mph at the time of the near miss.
The suspected drone was being flown at nearly seven times the normal legally permitted height of 400ft.
The pilot reported that the risks of a collision were “high”.
It is believed that the operator of the suspected drone was never found.
If convicted of endangering an aircraft they could have been jailed for up to 5 years.
Air traffic controllers informed other approaching aircraft that a drone had been spotted.
The report said: “Information on the drone was passed over the RT to aircraft following in the approach sequence.
“There were no further sightings and the aircraft following all landed without incident.”
Investigators said they were “unable to determine the nature of the unknown object”.
Aviation experts have warned of the dangers of a drone smashing a cockpit window or causing catastrophic damage to an engine.
Jet2 has not responded to a request for comment.