A drone came within 5 metres of crashing into a Boeing 737 passenger jet taking off from Stansted Airport.
The plane, with up to 215 passengers plus crew on board, avoided disaster by seconds in the near-miss at 4,000ft last September.
It is illegal to fly unmanned aircraft at more than 400ft without special permission.
But this was one of seven incidents in which drones flew too close to planes, says an alarming report by the UK Air Proximity Board.
Now airline pilots, fearing a "catastrophic crash", are calling for a clampdown.