Call recording requirements at Flight Information Service (FIS) aerodromes

Closed 14 Feb 2018

Opened 14 Nov 2017

Feedback updated 2 Aug 2018

We asked

We proposed that the requirement for the recording of a Flight Information Service (FIS), currently mandatory within CAP 797, but recommended within CAP 670 are harmonised and that both documents make the requirement mandatory. 

We asked about the impact of this change and proposed that all units offering a FIS service ensure they are providing recording facilities within a reasonable time scale. 

We proposed that so called ‘Custom PC based’ solutions where recording software is employed on a standard desktop computer are permitted as a temporary measure, and that such systems could be used as an interim solution for up to 5 years, by which point an appropriately approved recording system should be installed.

You said

We received 13 responses to our consultation.  8 from FIS units impacted and 5 from other stakeholders.  The majority of responses were in favour of the proposal, many appreciating the safety benefits such a requirement would bring, many identifying specific examples where the provision of recording has provided critical evidence or would have been beneficial if installed at the time.  A number of responses suggested that such recording should already be mandatory.  The addition of the availability of an audio recording when investigating an accident or incident brings significant evidence and reduces the reliance on evidence from memory.  Many responses appreciated the additional protection this brings for FISO staff.

Specific feedback included:

  • Concern that the requirement for minimum specifications would add additional cost.  The CAA believe that a set of minimum specifications is critical to ensure interoperability when playing back recordings and ensures that the recording recovery team can interpret recording files.  Additionally a minimum set of requirements also ensures the credence of recordings which is a critical factor in the protection and retention of evidence.
  • Another response highlighted the additional cost of recording land lines due to the technical complexities and differences in recording differing telephone systems.
  • One response highlighted the requirement for a safety case and the burden this places on units that will have to produce it.
  • A number of units expressed concern regarding the immediate cost of such a system and the continued maintenance cost of such equipment, along with the additional costs due to the requirement to ensure equipment is appropriately accommodated and powered.

We did

Following feedback we are maintaining our proposed approach, in light of some specific elements of the feedback we have made some minor modifications to the proposal and are investigating ways in which we can reduce the burden on individual units who have to install equipment.

As proposed in the consultation, The CAA will not require a full solution to be installed immediately, and for an interim period a PC based solution will be permitted.  Our research has shown that such a system can be purchased at a cost of between £600 and £1000 with little requirement for ongoing maintenance.  This system can be used for up to 5 years before a full system is required.  We believe this is a compromise that will allow time for units to establish funding for equipment whilst maintaining momentum behind the adoption of recording.  It also addresses units that have already made the investment in a PC based system and ensures a reasonable duration of use is achieved from such systems.  This time scale also considers the approaching introduction of the ATM-IR, which is likely to mandate recording of FIS.

The CAA understands that maintenance costs can be kept low and that some manufacturers offer maintenance packages as low as £400 per year.  Whilst the requirement will add some additional costs we believe the ongoing costs that would be passed onto the flying public are acceptable and that the safety benefits of mandating recording outweigh the financial impact.  As discussed within the original consultation, we are aware that a significant majority of FIS units already record radio transmissions.

We have reviewed the requirement for the recording of telephone systems and will modify this requirement to be highly recommended to reflect the considerable costs that could be incurred by having to record a wide range of different systems including VOIP (Voice Over Internet Protocol). 

Overall following feedback we believe the introduction of recording for FIS and the harmonisation of requirements as discussed in the consultation is beneficial for all.

What happens next?

Our intention, following this consultation is to update the relevant documentation to clarify this requirement.  As originally indicated, it is our intention to require all FIS units to provide recording services through appropriate recording equipment within 1 year, this includes the use of a custom PC based recorder, provided it is configured as required by the consultation document.  Finally, within 5 years recording should be provided through the use of appropriately approved systems (as specified within CAP 670).

Please Note:

Please note that the introduction of Regulation 2017/373 (ATM-IR)  may have an impact on the equipment requirements in future.  The CAA will provide updates on the rule making process as it progresses.  Any units making a purchase of equipment are recommended to discuss their requirements with the CAA so the latest information can be considered.


While Air Traffic Control (ATC) units are already required by the International Civil Aviation Organisation (ICAO) to record and retain two-way radiotelephony, the same requirement is not currently clear for UK Flight Information Service (FIS) units: it is non-mandatory under the requirements of CAP 670, but mandatory under CAP 797.
We propose that, in order to clarify requirements for UK FIS units:
  • the requirements in CAP 670 are changed to match those in CAP 797
  • radio telephony recording is made mandatory for all FIS units
  • all FIS units be equipped with at least a FIS-type recorder (a ‘cutdown’ ATC recorder). 
We believe the majority of UK FIS units are already doing this: a survey conducted by the CAA in 2012 indicated that roughly half of FIS aerodromes are equipped with some form of automatic recording equipment.
The recording equipment provided at some FIS aerodromes is similar to that provided at an ATC unit, but the equipment installed can vary between a custom PC-based solution and an MP3 recorder.
The replay quality obtained from these systems is therefore of concern to the CAA Transcription Unit, and users are encouraged to discuss their implementation with the CAA.
Custom PC-based solutions (such as specialist software run on a standard desktop PC) are a reasonable compromise for FIS aerodromes as an interim measure, provided that the hardware and software are appropriately configured and maintained.
The CAA has conducted research with a number of FIS units already operating this type of system, and established a set of parameters to ensure its suitability. We are proposing that such a solution could be used for a period not exceeding five years.

Why your views matter

In 2014, the CAA published the second edition of the Flight Information Services Officer Manual (CAP 797). Paragraph 22.32 of Section 9 requires the “recording and retention of data for investigative purposes”.

In order to support this requirement, the “recommendation” currently contained in the Air Traffic Service Safety Requirements (CAP 670), paragraph COM01.5, should be strengthened to a “requirement”.

The CAA is obliged to undertake an Impact Assessment before introducing any new regulatory requirement.

It is also expected that future regulation from EASA will require the recording of FIS stations, and the CAA requirements are expanding on the details of this.

Scope of the requirement

This requirement shall apply to all flight information services that operate within the UK for over 30 days (total) per year. This applies to continuous and staggered operations across the year for services run for specific events.

It is strongly recommended that short-term or temporary operations that operate for less than 30 days a year also record and utilise the requirements set out.

Recordings shall be required for radiotelephony messages and telephone conversations conducted during operational hours with other FIS units,  ATC facilities and airfield ground vehicles. These shall be retained by the FIS Unit for a minimum period of 30 days from the date of the last recorded message (as required by ICAO Annex 11, paragraph ).


  • Aerodrome Operators


  • Safety
  • Security