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UK – EU Transition, and UK Civil Aviation Regulations

To access current UK civil aviation regulations, including AMC and GM, CAA regulatory documents, please use this link to UK Regulation. Please note, if you use information and guidance under the Headings, the references to EU regulations or EU websites in our guidance will not be an accurate information or description of your obligations under UK law. These pages are undergoing reviews and updates.

A way to structure risk descriptions is the ECE Risk Expression, which gives a simple, clear description and assists risk assessment by identifying the adverse Event, likely Cause and the expected Effect. It is structured as follows:

E – what is the adverse EVENT?

C – what is the likely CAUSE? (hazards)

E – what is the expected EFFECT? (outcomes / consequences)

Example:

  • Event: aircraft control restriction
  • Likely Cause: loose tools in the cockpit
  • Effect: loss of control in flight
  • Risk description: loose tools left in the cockpit cause control restriction which leads to loss of control in flight
LIKELIHOOD: how often the Cause could potentially lead to the stated Event and result in the stated harmful Effect
Likelihood level Frequency descriptor: use available evidence and appropriate judgment to estimate the potential likelihood level
5 – Almost certain The Safety Risk (stated CEE) could occur at least once a month
4 – Likely The Safety Risk could occur at least once a year
3 – Possible The Safety Risk could occur once in 2 years
2 – Unlikely The Safety Risk could occur once in 3 years
1 – Rare The Safety Risk could occur once in 4+ years
IMPACT: estimation of potential harm, to how many people as a result of the stated effect
Impact level Descriptor: use available evidence and appropriate judgment to estimate the potential harm below
First and second parties Third parties
5 – Very High Such as following the loss of passenger carrying aircraft (est. 50+ fatalities) 10+ fatalities
4 – High Such as following the loss of passenger carrying aircraft (est. 20-49 fatalities) 3-9 fatalities
3 – Medium Such as following the loss of smaller passenger carrying aircraft (est. 10-19 fatalities) 1-2 fatalities
2 – Low Such as following the loss of smaller passenger carrying aircraft (est. 6-9 fatalities) Any serious injuries
1 – Very Low Such as following the loss of a small GA aircraft (est. 0-5 fatalities and/or any number of injuries) Any non-serious injuries

Note
Each Impact Level is derived from the result from the First/Second Parties column AND/OR the Third Parties column.

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