Determination of Causal Factors

Determination of Causal Factors

Best Practice – Determination of Causal Factors

  • Contact the pilots involved. Use a questionnaire to follow up infringing pilots to establish the cause of the incident.
  • Analyse replies and produce causal factors data to focus improvement actions.

Cost – Staff costs to follow up pilots and produce analysis


The EUROCONTROL data shows how difficult this can be to achieve, with 32% of causal factor data fitting into an “other” category. Often, unless a controller can speak to a pilot at the time of the infringement the cause can remain unknown. The Federal Office of Civil Aviation (FOCA) in Switzerland send out a questionnaire to every pilot that they can trace from the reports submitted to them by the ANSP. This has enabled them to compile accurate causal factors data, resulting in the active participation of GA bodies to help resolve what can be shown to be problem areas for pilots. Also, in the UK, the ANSP has recently started to contact every pilot they can trace and send them a follow up form to complete. In all of the work they have done, they regard this as the most effective tool that they have ever used for a number of reasons:

  • The cause of the infringement incident is fully understood by the ANSP and causal factor information can be accurately gathered to look for and confirm trends. This enables specific conversations to be had with GA representative groups and regulatory authorities with hard evidence of the areas of concern.
  • Accurate causal factors data now drives all future improvement initiatives.
  • The cause of the infringement incident is fully understood by the pilot. It is unlikely that, in many cases, the pilot had even realised that he had infringed controlled airspace until he was contacted. Instead of making the same error again through ignorance, the pilot has to do some self-analysis and is therefore less likely to make the same error again.

It is this engagement by the pilots in the resolution of the problem that is proving successful in Switzerland and the UK. This approach has brought about a general “breaking down” of barriers between the ANSP, the Regulator and the GA community. GA representative bodies are now fully engaged in trying to prevent airspace infringements, including running safety evenings, carrying out presentations on the subject and also writing regular articles in GA magazines. The UK CAA regard the engagement of the GA community as a major step forward in tackling the risk of airspace infringements and following up with the pilot in a pro-active way has been fundamental to this new relationship.

Sample Material

UK Analysis of Causal Factors Data

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