• Airworthiness Approval Notes (AANs) represent an approval at a point in time. The approval holder going out of business or changes to CAA policies or requirements do not necessarily cause updates to the AANs. The designs covered by AANs may therefore no longer be available under the same conditions or even at all.

    Whilst the AANs are publicly available, readers should not assume that technical reports, drawings or documents referred to therein are also publicly available.

    AANs do not, intentionally, contain sufficient information from which to "copy" a design, evidence of identicality is the responsibility of applicants for design approvals where they are attempting to oblige the CAA to make use of technical information it already holds for the purposes of easing the path of subsequent approval for a similar design.

    Most AANs issued after AAN Number 21700 and some earlier AANs that have been re-issued after 29 July 2002 are available from this site. Documents prior to 1992 were not usually stored electronically and are consequently only available as a paper copy.

    There are currently no plans to provide these in an electronic format.

    AAN Database Search

    • The AAN Database contains the details of over 30,000 AANs and can be searched using the  Database Search function.

    Frequently asked questions

  • It is a function of the Safety Regulation Group to issue Certificates of Airworthiness or permits to fly to allow aircraft to fly in compliance with the UK Air Navigation Order 2009. Implicit in this activity is the task of agreeing the standards to be applied, and that compliance with those standards has been shown in the particular case by the Applicant for the certificate or permit. A similar activity is required to approve modifications so that a Certificate of Airworthiness or permit may be issued or reinstated for a modified aircraft.

    The Airworthiness Approval Note is a document which records the approval that the particular certificate or permit may be issued (or reinstated following modification). In so doing the AAN provides a record of (either directly or by reference to controlled documents) the build definition of the aircraft or modification, the standards that have been applied, the justification of compliance with those requirements, any restrictions or limitations affecting the approval, and a statement of approval.

    Fields on database search screen

    AAN No. This is normally just a number i.e. 27777 (some of these AAN numbers will have the suffix 'P'. This was used in the early 90's to indicate the AAN was for a permit to fly.
    Applicant This is usually the organisation or individual that made the application (the applicant is the owner of the AAN). 'CAA Internal purposes' is used here if the AAN has been generated by the CAA and not via an external applicant.
    Aircraft Type The aircraft type should always match the aircraft type shown on the UK Aircraft Register for UK registered aircraft (older AAN's may not adhere to this standard).
    Mod No. The modification number used by the applicant (can be numbers or text).
    Registration Mark This includes foreign aircraft registrations as well as UK aircraft registrations.
    Serial No. Serial number of aircraft (This is not an aircraft line number or military registration).
    Subject This describes the content of the AAN. This is normally a short description of the contents of the AAN and will reflect the modification title shown on the AAN document.
    STC This field contains a Supplemental Type Certificate number if the AAN approves a foreign STC. Just type the number of the STC in this field. To improve the chances of locating the STC just use the numbers not characters i.e. 6789 not SA6789-D. Please note that this field includes any foreign approved STC's not just FAA STC's.

    Extra fields shown on the database search return screen

    Issue Issue status of AAN (if there is no number the AAN is at original issue).
    Addendum The addendum number (if applicable).
    AAN Date This is the application date.
    Issue The second issue field is used if an addendum has been re-issued.
    Approved Date This is the date that the regional office surveyor approved the modification.
    Final Date This is the date the AAN was issued. If the AAN was issued without a regional office inspection then there will be no approved date on the record. The AAN has not been issued if there is not a final date showing. However, prior to the recording of data on the AAN database in the early 1990's the issue or approval of the AAN may not be recorded.
    Cancelled Date Occasionally an AAN will be cancelled, usually because the applicant decides not to progress the modification further. The date that the CAA actions the applicants cancellation request is shown here.
    • Issues - Where it is necessary to amend an AAN at Final status to correct errors, improve clarity etc, the AAN is re-issued. The first re-issue will be issue 2, any subsequent re-issues will be raised in sequential numerical order.
    • Addenda - Where the Applicant (named on the particular AAN) requires the scope of the approval to be extended, an Addendum to the AAN will be requested. The Addendum will be considered as supplementary to the basic AAN at latest issue.