Reporting air safety concerns

Military Aviation Authority (MAA) guidance to personnel from across the defence air environment on how to report air safety concerns.

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 standardised reporting format and management system for DAE personnel to use.

Air safety information management system (ASIMS)

ASIMS is a MOD software 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, users can navigate to ASIMS in any browser.

For access to ASIMS, contact your local air safety point of contact or the ASIMS Helpdesk at

ASIMS training and reference material

ASIMS users should undertake the appropriate training packages for their role/requirements prior to using the system.

ASIMS user training courses are available through ASIMS with further guidance and information available in the ASIMS user manual.

Defence air safety occurrence report (DASOR)

In accordance with Regulatory Article (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; including for example: airprox, birdstrike, air traffic management and loose article reporting forms.

The primary method for submitting a DASOR is through ASIMS. This application is available from any MOD or personal device connected to the internet by navigating to the following URL:

If you are unable to access ASIMS, then PDF versions of the DASOR document suite are available below. Once complete, send the PDF documents to your home unit for submission onto ASIMS directly.

The ASIMS user manual provides guidance on how to complete a DASOR.

Error reporting

Error management systems will also use the DASOR to record air safety information; however, individual ships / stations / establishments may have their own local management procedures in place, which will include options for individuals to report non-air safety hazard observations.

There may also be occasions when an individual is unable or unwilling to complete a DASOR and where a readily available, paper form option would be advantageous in capturing errors, observations, risks or hazards. The In-Form is the approved reporting form and should replace any legacy Defence aviation error management system (DAEMS) forms within all ships / stations / establishments. Typical examples of when the In-Form may be used are detailed below and completion instructions are detailed on the form;

  • any safety related issues
  • near misses of any type whether air or functional safety
  • any safety hazards such as those affecting flight safety, airworthiness or health and safety
  • any quality concerns
  • any continuous improvement ideas
  • any organisational failings
  • any issues that make human error more likely

For further information, contact your local ship / station error management systems coordinator.

Defence confidential occurrence reporting scheme (DCORS)

ASIMS has the functionality to submit DASORs anonymously to improve the trust and honesty in air safety reporting. If reporting an air safety occurrence anonymously falls outside of routine reporting parameters, then any military, civilian and contracted personnel can report via a Defence confidential occurrence reporting scheme (DCORS) form. The form is available below and further information is available in RA 1410.


Published 14 November 2014
Last updated 1 November 2022 + show all updates
  1. The information on this page and been reviewed and updated.

  2. ASIMS training course information updated.

  3. The Significant Occurrence Notifications (SON) form has been added.

  4. ASIMS is experiencing accessibility difficulties through the Internet Explorer web browser on Windows XP.

  5. First published.