Published date: 4 February 2022

In October 2021 the CAA approached aerodrome operators, following up on our earlier request for updated traffic movement figures (rule 139.505 Reporting traffic volumes). We’ve received some questions about 139.505 and our request, so we’re outlining here why we want these figures and what we do with them.

The CAA requires this information so we know how best, and where best, to use our finite resources. Fundamentally, the numbers allow us to identify where our oversight is, or isn’t, needed. The movement data also allows us to develop incident rates, and therefore trends in risk.

Aerodrome movement data is important for aviation safety management at both an operational and a regulatory level. The data is used to monitor activity at aerodromes and to track various incident rates, for instance, bird strikes. But it’s also critical for oversight by the CAA and aerodrome operators, and so everybody can continue to fly safely.

All aerodromes – whether certificated, public or private – present various risks which must be identified and controlled. An understanding of such risks means we have to be aware of the amount and nature of activity at any given aerodrome. Without this data, adequate aerodrome safety management isn’t possible. As a risk-based and intelligence-led regulator, this data helps us focus our efforts on key risk locations.

Here’s an example of the analysis we can develop when we get good movement data:

While the rules do outline specific requirements, we acknowledge the need for the Authority to be pragmatic. While at times we do require actual figures, in some instances we’ve accepted estimated numbers of movements. On other occasions we’ve advised aerodromes they don’t need to report numbers of movements, because of the type of activity at their aerodrome – for instance, agricultural airstrips.

Estimates of traffic volumes are an acceptable means of compliance and minimum compliance with the rule shouldn’t be a significant imposition on aerodrome operators, because they should be aware of traffic volumes and types of activity.

The Authority has an online tool to help aerodromes operators with their report: 24139/06 - Rule 139.505 Movement Data Reporting for Non-Certificated Aerodromes [XLSX 535 KB]

We’re happy to work with aerodrome operators to improve the online reporting tool to make sure that complying with the rule is a quick and easy process.