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UK Civil Aviation Regulations

These are published by the CAA on our UK Regulations pages. EU Regulations and EASA Access Guides published by EASA no longer apply in the UK. Our website and publications are being reviewed to update all references. Any references to EU law and EASA Access guides should be disregarded and where applicable the equivalent UK versions referred to instead.

UK Mandatory Occurrence Reporting

ECCAIRS2 Aviation Reporting Portal

Mandatory Occurrence Report (MORs) has been a part of the fabric of UK aviation operations since 1976. Reporting is mandated by UK Regulation 376/2014 which requires the reporting of safety related occurrences involving UK airspace users.

Occurrence reporting helps improve aviation safety by ensuring that relevant safety information is reported, collected, stored, protected, exchanged, disseminated, and analysed. It is not to attribute blame or liability but supports continued learning to make flying safer.

UK organisations must report to the UK CAA. The only exception is for occurrences that involve Annex 1 (non-EASA) aircraft. For these occurrences reporting is strongly encouraged but currently remains voluntary.

ECCAIRS (European Co-ordination Center for Accident and Incident Reporting Systems) provides a digital platform to integrate European National Aviation Authorities (NAA’s) and Safety Investigation Authorities (SIA’s) to enable the implementation of the provisions defined in regulation 376/2014. More information on ECCAIRS, and the safety benefits of reporting is available on ECCAIRS2.

During an average year we received around 30,000 occurrence reports, although in 2020 this reduced to around 18,000 due to the coronavirus pandemic. These reports help us to continue to work proactively, helping us identify safety concerns and allowing measures to be implemented before they escalate.

Voluntary Occurrence Reporting

Voluntary Occurrence Reports (VORs) are reported in the same format as MOR as all reports are triaged and prioritised individually, processed, and then analysed together.

Voluntary reports are classed as:

  • Occurrences not captured by the mandatory reporting system
  • Other safety related information which is perceived by the reporter as an actual or potential hazard to aviation safety


Occurrence reports are treated confidentially to maintain full and free reporting and protect the identity of the individual.

Requesting MOR information

Occurrence information can only be used to maintain or improve aviation safety. This means that we can't release occurrence information to the general public or to the media, including in response to Freedom of Information Act (FOIA) requests.

If you have a requirement for occurrence report analysis or listing, these can be requested using our SRG1604 and SRG1605 forms. These requests allow for the release of occurrence reporting data to support safety improvement activities.

SRG1604: Application for monthly MOR listings
SRG1605: SRG1605: Application for MOR Data Release for the maintenance or improvement of aviation safety

The value of occurrence reporting

Occurrence reports are a core data source used to inform our decision and policy making. We make frequent use of occurrence data to identify safety trends, hazards, risks and issues that have the potential to impact on the safety of the UK aviation system.

We also support numerous academic and safety related studies through the provision of analysis and de-identified datasets.

What should be reported

Any occurrence that you feel could have an impact on aviation safety should be reported, this will ensure that we always review and learn from events.

The detail given in IR 2015/1018 is a plain and simple list classifying occurrences in civil aviation to be mandatorily reported.

How reports are made

You can use the ECCAIRS2 Aviation Reporting Portal to submit MORs to the UK CAA (and EASA member states).

It is designed to allow reports to be submitted from individuals and organisations.

If your organisation is submitting a high volume of reports it may be easier to use an ECCAIRS compatible (E5x) file or reporting software solution.

ECCAIRS (E5x) file format

If you have an internal reporting system, it may be possible to submit MORs using in an ECCAIRS compliant format (also referred to as an E5x file).

An E5x file uses an xml/xsd specification to send occurrence report data based on the attributes and values contained within the Reduced Interface Taxonomy (RIT). More details about this specification can be found on the aviation reporting portal

Approval must be granted by the UK CAA before an E5x file can be submitted. This is to ensure that the structure and contents of E5x files is compatible with our occurrence reporting database.

For more information about E5x reporting, please contact safety.intelligence@caa.co.uk

Reporting software solution

For larger reporting organisations and those who seek to produce a compliant format report directly from their own reporting system, advice on how to produce and submit occurrence reports can be found here.

More information

Contact the Safety Intelligence Team: Safety.Intelligence@caa.co.uk

Safety reports and reviews