What is Direction Finding?

When you call the emergency services on land, the despatcher is able to determine your location in just a few seconds thanks to your phone’s internal GPS and the location information available on the cellular network. However, what happens when there is an emergency at sea, in the middle of the desert or in the height of the mountains where a GPS position cannot be determined?

Search and Rescue crews aboard aircraft still rely heavily on Direction Finder (DF) systems to determine those in distress even when those individuals themselves are unable to determine or communicate their position. While GPS and other newer technologies become more dominant in the SAR and C-SAR arenas, you would think it would be easier to find those in distress but that is not always the case.

For many years, GPS has been labelled as the answer for many search and rescue needs however, it's not enough to simply rely on GPS for SAR missions. There are multiple beacons still in service across the world working on a variety of legacy frequencies. If SAR equipment doesn't cater for all instances or frequencies, then some emergencies could take longer or even missed altogether - leaving no peace of mind for the rescuer.

Instead, DF which operates on and is certified for use on both legacy and modern beacons, is the only system which can provide true peace of mind for search and rescue crews. Future-proofed so that newer beacons are detectable; not forgetting the legacy ones still in use.

We have heritage in DF; delivering equipment for over 60 years to guide Search and Rescue crews. With Chelton DF on your team, searches are more efficient, more accurate and faster; all critical especially in harsh environments when you are up against the clock.

  • Extended Range
  • Multiple Beacons
  • Broader Frequency Coverage
  • Trusted by many
  • Platform Tailored

Chelton's DF family has been meticulously designed to maximise range whilst not compromising size, weight and power characteristics. 

The design of Chelton's 935 DF Antenna has been proven in a customer trial to have had 3x the range detection when compared to other competitor systems.

If you'd like to know more about these results and performance, please contact us below.

935 1 New

With decades of experience in the antenna industry and having worked closely with agencies, our design enables peace of mind for the user and ease of operation.

Chelton's DF family has the unique ability to both continuously and simultaneously monitor separate frequencies using 6 receivers built into the system in parallel meaning beacons can be found, quicker.

Close Up Of Pilot In Heli

Chelton's DF covers up to 9 SAR frequency bands depending on the applications of your aircraft.

This is more than alternatives in the market including Tactical VHF, Marine Distress, COSPAS/SARSAT and more.

1071001820 RT 7000+AW139 300Dpi

From the lightest utility helicopters to the largest military transport jets, Chelton's DF family is certified for use across a large number of commercial and military platforms.

Our superior DF equipment is used across the world by a diverse set of agencies including coastguard, emergency services and military agencies for both SAR and civil and combat SAR.

MH 60R Lockheed Martin

With Chelton’s expertise and our advanced modelling techniques such as digital twinning, we can decode your requirements and advise you on the best DF configuration for your platform to maintain optimal RF performance.

In addition, each implementation can be supported by our team of in-house experts.

Airgreen AW139 From Remote (12)

When it comes to performance, Chelton comes top of the class

The design of Chelton's DF family is such that it outperforms other systems in a number of areas including:

  • Broader Frequency Coverage

Chelton's DF family can cover up to 9 different frequencies with the ability to monitor 6 simultaneously giving you confidence in your aircraft's ability to locate beacons. This includes Tactical VHF, Marine Distress and COSPAS-SARSAT depending on the application and requirements of your platform.

  • Low Airframe Protrusion

Chelton's antenna experts focus designs on optimal RF performance without sacrificing on size, weight and power; that's why our DF family offers the best performance to drag ratio with the lowest amount of airframe protrusion combined with largest frequency range.

Conformal options are available in the market but the reality is that this is only ever a reasonable solution for platforms at the beginning of the design and not for existing helis in operation.

When it comes to the best all-rounder, Chelton DF comes top of the class.

  • Flexibility

The Chelton DF family offers not only flexibility in use but also flexibility in operation and installation. The DF family is configurable for both SAR and C-SAR and because of the broader frequency coverage we can offer, Chelton's DF will be easy to use for however your agency needs to; whether that's marine bands for coastguard rescue or tactical VHF for mountainous terrain.

Thanks to our large install base, we know exactly how best to install a DF system based on your platform and your requirements including different plinth options to ensure protrusion is as low as possible while still functional to work at lower altitudes.

Chelton Direction Finder Systems - giving you peace of mind for your search and rescue operations

Contact Chelton, Marlow (Head Office)

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