An RAF tanker aircraft and two F-15 fighters narrowly avoided a catastrophic collision over the North Sea when a flight controller was distracted by a phone call.
The F-15 travelling at 402 mph (643km) was so close to the RAF Voyager that its crew could feel the turbulence before they turned on afterburners to avoid the crash on 5 January 2017 around 10 miles (16km) off the coast of north Norfolk.
After the near miss, a pilot on the tanker told flight controllers that he and his crew "were very close to not being there anymore".
The incident was revealed in a report by the UK Airprox Board, which said the F-15s had flown "into conflict" with the Voyager but it also blamed air traffic controllers and misunderstandings between them and the US pilots.
There appeared to be confusion after the F-15 pilots said they would flying into the Wash area when they meant the wider Wash Aerial Tactics Area where the RAF tanker was flying.
Thinking there were not close to each other, the controller in Stanwick, Hampshire, answered a "distracting and complicated" phone call and was unable to stop the F-15s mistakenly flying into the zone which was being used by the Voyager crew for mid-air refuelling.
The RAF probe concluded that the controllers "did not effectively prevent the F15 from entering the airspace around the Voyager" and its report made 15 recommendations to stop it from happening again, the Telegraph reported.