Amanda Rhodes, NATS air traffic controller at Swanwick Centre looking after airspace around Luton Airport, talks about her experience with airspace infringements for this week’s Infringement Series story…

Airspace infringements have been an issue for as long as I can remember, not just at NATS but for other Air Navigation Service Providers (ANSPs) too. Over the years NATS has developed tools to help us manage them as far as we can, including modifying some airspace and local flying areas, and have carried out lots of engagement activities in a bid to educate pilots – most of whom we know take their responsibilities  seriously.

As a controller, if there is an aircraft which we believe to have infringed controlled airspace I need to take immediate action to achieve 3 miles lateral or 3000ft vertical separation from the unknown aircraft. If I have a long stream of inbounds, managing the traffic situation can become very complex very quickly. I will assume the pilot of the infringing aircraft is lost and their intentions are unknown.

“I will assume the pilot of the infringing aircraft is lost and their intentions are unknown”

Once I’m confident my IFR (Instrument Flight Rules) aircraft are safely separated from the unknown aircraft I will try to establish contact. For pilots operating on a listening squawk the issue can be resolved very quickly, but even if they’re not I will still make a few blind transmissions on the off chance they may be listening.  If there is no response I’ll be trying to figure out where they might be flying from or to or whether they’ll be in contact with a different air traffic unit. All of this is happening whilst trying to manage my IFR traffic.

If I can’t contact the aircraft and the infringement continues, to keep the situation safe I’ll have no choice but to give non-standard manoeuvres to my IFR traffic and also stop any further arrivals. The stacks can then fill up very quickly, adding further pressure to me and my colleagues.

Once the aircraft departs controlled airspace I have to start the process of re-establishing aircraft back onto the final approach.

“If you are flying around and you think you are lost or you are unsure of your position, please talk to us.”

After I unplug from my position I will then have to start all the paperwork. If I have had a loss of separation I might not be able to control until the incident has been investigated. If deemed appropriate I can then return to duty, but if further investigation is needed then it’s not that simple.

It can be very uncomfortable– not to mention the risk it places on passengers  so if you are flying around and think you are lost or you are unsure of your position, please talk to us.  People think that speaking to ATC can be scary but I assure you, infringements can be much scarier.

“You have no idea what the pilot is about to do next.”

Often when we contact infringing pilots after the event we hear “It was only a short infringement” or “it was only a few hundred feet”.  In hindsight that might be correct, however we won’t know that at the time. When you’re sat in front of a radar screen and see an aircraft outside controlled airspace climb to 1600ft, 4 seconds later it appears at 1700ft and then 1800ft.

Those 4 seconds can feel like a very long time.  You have no idea what the pilot is about to do next.  We might issue avoiding action to an aircraft only for the Infringing aircraft to descend or turn immediately further complicating the situation.

We also often hear that “there’s too much airspace”, and “aircraft climb rates aren’t what they used to be” or “you don’t need airspace down to 2,500ft”. What some people fail to appreciate is that the airspace has to be designed with the lowest common denominator in mind in terms of aircraft performance. Departing aircraft generally do climb quickly, but what about arrivals or if an aircraft carries out a missed approach? We want to ensure the aircraft can do the manoeuvres required whilst contained within controlled airspace.

So please remember, if you think you have entered controlled airspace please call ATC as soon as possible so we can identify you and resume normal operations. That way there’s no dramas, for us or you.

According to the Civil Aviation Authority, in 2018 there were a total of 1,358 reported airspace infringements. Analysis of reports from 2017 has shown that:

  • The correct use of a moving map with alert could have prevented 85% of infringements
  • Using an frequency monitoring code (Listening Squawk) could have prevented 65% of infringements
  • Recognition of/dealing with overload, fixation and distraction – possibly effective in 43% of cases
  • Better familiarity with aircraft and equipment – possibly effective in 24% of cases

Pilots are encouraged to request entry into controlled airspace as early as possible, either by free call, radio transmission or our Airspace Users Portal.

Via the portal,, pilots can submit a CAS request before their intended crossing so our controllers can prepare for their arrival – helping pilots with their requests and enabling safer use of the airspace.


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Kev Barnes

A good article, thanks. How are drones / UAVs / RPAS dealt with with regard to Air space infringement? I expect they present quite a challenge.



Andreas Wuerde

As an ATCO in Germany I read, that You are not allowed to work if an infringement of Separation occurs. Is that true for all controllers from NATS? What are the Procedures if you fail to maintain prescribed separation?

Cheers from Germany

Andy “WU” Wuerde
Rhein Radar UAC



Jim V

Bravo Amanda for your nice article. I am an ancient retired ARTCC controller in the US. I started out in the Centers when it was non-radar environment and then transitioned to a broadband Radar to the. Present digital Radar control here in the National Airspace System in the the US. In the US we had the same process essentially of dealing with airspace enfringements as your NATS controllers. I enjoy following your NATS blog Amanda and wish you and your colleagues continued success in your career. Sincerely, Operating Initials: Juliet Victor



John Webb

Excellently expressed. Thanks




I don’t agree with your idea of online CAS submissions and am happy to explain why but this box is a bit too small.

Hi Andreas
If a suspected loss of separation occurs, the controller can be relieved from duty while the event is investigated, replays are looked at and the radar replay is matched to the voice recordings. The controller also has to file a Mandatory Occurrence Report.

Hi Kev
As recent events have shown, drone infringements do present a challenge when they stray into controlled airspace. Drones can have a massive effect on air traffic operations, not least because they don’t show up on air traffic control radar. At NATS we take reports of drone sightings very seriously and will always ensure we put safety first in the way we respond to reported infringements.
In the past couple of years we’ve seen an increase in air proximity reports involving drones, so it’s especially important that drones are always flown safely and responsibly, away from controlled airspace and according to the drone code, which encourages drone operators to keep their drone in sight, below 400ft (120m) and away from people and property at all times – and, since the law changed earlier this year, it is illegal to fly a drone within 5kms from an airfield without specific permission from air traffic control.
More information is available from our DroneAssist app and the DroneSafe website, and via the NATS Airspace Users’ Portal.
Mark Watson, Manager UTM Strategy & Service Integration




Interesting read… A far departure from West Drayton. Well done you.


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