As the flying season is now well underway, we thought we’d provide a deeper look over the coming weeks, at some of the services that are available to pilots. Today we’re starting with the Lower Airspace Radar Service (LARS).

The LARS service at Farnborough has provided advice on avoiding infringements of controlled airspace on more than 1000 occasions per year since January 2009 when the service was introduced and is available to all GA pilots operating in the area covered.

Farnborough provides a service for south east England not only for airspace users who are flying underneath the London TMA, but also aircraft flying in close proximity to the edge of other major airfields’ airspace.

A LARS controller’s main priorities are to provide advice and useful information for the safe and efficient conduct of flight. In the south east especially, their other priority is to help GA pilots avoid accidently infringing controlled airspace. In doing so they also create and maintain a “known” traffic environment, within which both GA and commercial airline pilots can operate safely.

A LARS controller can provide pilots with three different levels of service:

  • A basic service is a type of UK Flight Information Service (FIS) provided for the purpose of giving useful advice and information such as weather information, serviceability changes, conditions at aerodromes, general airspace activity, warnings about airspace restrictions and other information likely to affect safety. It will also include information on other aircraft which the controller sees and believes to pose a high risk of collision. However, under a basic service, the controller is not required to and cannot always physically maintain a constant watch on each aircraft, so there is no guarantee that such information will be passed
  • A traffic service (TS) is a surveillance based FIS where in addition to the provisions of a basic service, the controller will provide traffic information to assist pilots to see and avoid other traffic
  • A deconfliction service (DS) is a surveillance based FIS where in addition to the provisions of a basic service, the controller will provide traffic information on conflicting aircraft along with headings or levels to fly at in order to resolve the confliction. The pilot is at liberty to ignore such advice, but must tell the controller he is doing so and becomes subsequently responsible for avoiding the other aircraft
  • It is important to remember that, regardless of the service being provided, it is ultimately still the pilot’s responsibility to avoid other traffic when operating outside of controlled airspace. Also, where a controller is very busy, a traffic service or deconfliction service may have reduced traffic information or may not be able to be provided at all, so pilots shouldn’t get airborne counting solely on a radar service to get them through busy traffic or bad weather en route.

Upon requesting a service, a controller issues pilots with a squawk code particular to the ATC agency they are working. This allows controllers to identify them and shows any other controlling agencies in the vicinity who are working the traffic. In the busy south east, a known squawk also gives reassurance to TMA controllers that the aircraft is less likely to infringe controlled airspace, and more likely to be quickly pulled out if it does.

So if you’re out flying this weekend, don’t forget that the LARS service is available to you and can provide assistance. By working together in this way, we can ensure that infringements are avoided and a safe environment is provided for the whole flying community.

For more information on how to avoid infringing controlled airspace:


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Aldo Muir

“As the flying season is now well underway” ?

Have I missed something ? When did it stop ?

You’re a FISO ?



Ministry of Flying

Great stuff Sean but your article seems to be about Farnborough,flying life does exist north of the Home Counties too!

Poor participation in the LARS service is a major problem, the PPL Skill Test requires a MATZ or CA transit but also should need to require the candidate to show successful participation of a LARS service too. If more pilots used LARS I think there would be less illegal penetration of CA

Many instructors set bad examples by flying in the local area with the base airfield tuned in when a better service could be obtained by using a LARS. Being able to contact a LARS for a VOLUME LOW service would be really helpful too EG Shawbury G-ON operating in block 500- 3500 feet Bridgnorth-volume low. At least Shawbury would then know what was happening and could issue a dedicated squawk.

Most candidates/students/instructors do not understand the range of a LARS mainly because it always seems to be missing from article on LARS! I teach contact at 40 and expect a service at 30 from the head.

The FIS seems to prevent pilots from contacting LARS, many pilots will contact the FIS as a first choice rather than a LARS. This habit needs to be broken and the FIS needs to considered a secondary option when LARS isnt available.



Robert Baldwin

Would have been nice to say that the Deconfliction service is only available for IFR flights



Phil Simpson

I often fly in the Farnborough West area in my PA28 and I cannot understand why Farnborough West does not have a listening sqwark. I have installed a mode-s transponder and you could call me up even when I am sqwarking 7000 and just listening in as there is too much for the controller to handle. Thanks for the LARS service but a listening sqwark would help in my opinion



Phil Simpson

See my post and write Farnborough East



Keith Miller

Hi Phil, only had my PPL for a month and I could be wrong however with ref listening SQUAWK for Farnborough West please see below

Farnborough LARS West
If you intend to fly within 8/10miles of Farnborough or through the OCK to Biggin Hill corridor then we strongly advise you make yourself known to Farnborough Radar. If you are not operating in these areas (see map below) and either cannot get in on a busy frequency or would just rather listen out on frequency then you can squawk 4572 whilst
listening on 125.250.

hope that helps



Philip Watkins

An aircraft with a mode s transponder as well as squaking the set code also transmits its call sign and this is visible on radar screens. Why do controllers require a change of squak from 7000 when the aircraft is already clearly identifiable?


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