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Home > Occurrence Reporting

Reporting Air Safety Concerns

The proactive reporting of Air Safety concerns by personnel from across the Defence Air Environment (DAE) is fundamental in maintaining continual awareness of the risks facing our people.  To enable and facilitate such reporting, the MOD provides a standardized reporting format and management system for DAE personnel to use.

Defence Air Safety Occurrence Report (DASOR)

In accordance with RA 1410, the DASOR is to be used to report all Air Safety related occurrences, be it notification of an event which has already occurred or identification of a potential Air Safety hazard i.e. a Hazard / Observation. In addition to the standard DASOR, complementary forms are available for specific specialist occurrences which require further information from the reporter i.e. the Airprox Report, Birdstrike Report, Air Traffic Management Report, MALDROP Report and the Parachuting Report.
The primary method for submitting a DASOR is through the Air Safety Information Management System (ASIMS). This application is only available on internal MOD networks by navigating to the following URL: If you are unable to access ASIMS, then PDF versions of the DASOR document suite are available in the pane on the right hand side of this page. Once complete, send the PDF documents to your home unit for submission onto ASIMS directly.

Air Safety Information Management System (ASIMS)

ASIMS is an RLI-based tool used for the reporting, management and exploitation of Air Safety occurrence and investigation information.  ASIMS is a dynamic system allowing the most up to date information to be recorded as it becomes available.  
To log into ASIMS DII(f) users can navigate to in your browser.
For access to ASIMS, contact your local Flight Safety point of contact. 
 ASIMS Training and Reference Material
ASIMS basic user training courses are available from the Defence Learning Portal.  


Error Management Systems will also use the DASOR to record Air Safety information; however, individual Ships/Stations/Establishments will have their own local management procedures in place, which will include other options for individuals to report non-Air Safety Hazard / Observations.  For further information, contact your local Ship/Station Error Management Systems Co-Ordinator (SEMSCO). More information on Error Management and the DAEMS programme can be found on the DAEMS page.

Defence Confidential Occurrence Reporting Scheme (DCORS)

This process covers all military, civilian and contracted personnel and allows the anonymous reporting of Air Safety occurrences which fall outside the normal reporting parameters. For further information see RA 1410.