UK investigators have revealed another two serious drone encounters with commercial aircraft took place in the same week as three previously-disclosed incidents.

The encounter involved an Embraer 190 departing London City on 20 July. It had been conducting a right turn at 2,700ft when the first officer saw the apparent drone ahead and slightly above the jet.

UK Airprox Board investigators state that the first officer believed there would be no collision if the Embraer continued its turn and maintained its climb rate, and the vehicle passed down the left side of the aircraft.

The crew had estimated the separation as 30ft vertically and 20m horizontally.

In its assessment the board categorised the encounter as bearing the highest collision risk, adding that the drone was “beyond practical” visual line-of-sight of its operator, who could not be traced.

The board had previously detailed three other drone encounters affecting London Heathrow flights during 16-18 July.

It adds that another serious airprox occurred at Manchester airport on 20 July, involving a Boeing 767 on final approach to runway 23R. While the board says the 60cm object encountered “did not look like a drone” to the crew, it says it “did not look like a balloon either”.

The board says the object was level with the cockpit window and close enough to have probably passed over the starboard wing. It has treated the object as a drone in its assessment, adding that the operator could not be traced.

Investigators have also detailed another serious London encounter, which took placed about two weeks later, when the crew of an Airbus A320 in the Biggin holding stack for Heathrow identified a drone at 11,500ft some 20-40m from the aircraft. The board says the drone was “about the size of a football” with a flashing magenta light.

There was “insufficient time” to react or avoid a potential collision, says the board, adding that another aircraft reported a drone sighting about 2min later.

Source: Cirium Dashboard