Sunday’s incident at Gatwick, where a drone spotted on the airport’s final approach path caused the runway to be closed for two separate periods, has understandably received a lot of press coverage.

The incident caused significant knock-on effects for air traffic control, beyond just stopping arrivals while the runway was closed and caused serious disruption in the sky above southern England.

It is always the airport’s decision whether to close the runway to arriving aircraft. Safety is always going to be the number one priority and Gatwick was left with little choice on this occasion, given the location of the drone.

Our job is to work with the airport to manage and minimise the disruption caused by such a closure. This is no small challenge when you’re talking about the world’s busiest single runway airport in some of the world’s busiest airspace, particularly during a busy summer weekend. I was in the Operations Room when the call came in on Sunday.

Our first job was to divert aircraft coming into land away from the runway. This meant tactically manoeuvring aircraft to avoid the runway, which significantly increases controller workloads. This is where a controller’s extensive training really comes to the fore, managing multiple aircraft in a relatively confined area of airspace…and keeping them safely separated at all times.

We directed the aircraft back to the two holds that support Gatwick – one called Timba to the South East of the airport and another called Willo to the South West. You can see this in the radar replay footage below. With the runway closed, these holds soon started to fill up and it wasn’t long before we had to open the contingency hold – Mayfield – as well.

Radar replay footage of the incident at Gatwick on Sunday as seen by Air Traffic Controllers. Overflights and flights to airports other than Gatwick have been removed for illustrative purposes.

The next challenge is dealing with any required diversions as aircraft continue to burn fuel whilst they wait to land. Airlines carry a set amount of fuel for their scheduled journey, with a contingency amount for unforeseen circumstances, but after a while spent burning fuel in the hold and without knowing when a runway is going to re-open and, pilots have to consider whether diverting to an alternative airport is the safest option. On Sunday, four aircraft had to divert – one to Stansted, one to Southend and two to Bournemouth.

At the same time, we were also looking at other ways to slow the flow of arriving aircraft in to the airport. This included introducing an ‘en-route’ hold near the Solent, with some aircraft held far away from the airport and at higher altitudes while they waited for the backlog to clear. This saved clogging up the airspace immediately around the airport even further, as well as reducing fuel-burn for aircraft as the en-route holds at higher levels are less fuel-intensive than the standard arrival holds.

We also had to place a flow regulation on arriving aircraft, which led to aircraft due to depart for Gatwick from elsewhere delaying their take-offs.

The disruption was significant and took hours to clear; it was around midnight before everything was fully ‘back to normal’ and even then, hundreds of passengers had ended up away from their intended airport and thousands of passengers had been delayed. All as a result of one drone pilot flouting the rules.

Drone users have a responsibility to others in the air, just as any other pilots do. It’s their responsibility to fly safely and to respect other users of the airspace. It’s hard to imagine this drone pilot didn’t know that what he was doing would disrupt the airport’s operations.

If you know anyone who’s planning to fly a drone, please, make sure they read the CAA Dronecode and download the Drone Assist app before they fly so that they fly safely.