Catalogue description Air Registration Board and Civil Aviation Authority, Airworthiness Division, Design and Manufacturing Standards Group: Airworthiness Approval Notes

The Design and Manufacturing Standards Group investigates the design of a new type of aircraft for compliance with the applicable Airworthiness Requirements and once it is satisfied that compliance has been established, it is recorded in an Airworthiness Approval Note (AAN). Similarly, AANs are used to record the basis on which compliance has been established in relation to any major modifications to an aircraft. The approval of engines and propellers, including the basis on which certification is given is signified by an engine (or propeller) Approval Letter.

An Airworthiness Approval Note (Permit) (AAN(P)) is used to record the basis on which the Civil Aviation Authority may issue a Permit to Fly for an aircraft even though the aircraft may not be required to show compliance with a formal civil airworthiness code (eg an historic or ex-military aircraft). An AAN(P) is also used for microlight aeroplanes which are in compliance with appropriate airworthiness codes, but for which the Authority does not issue certificates of airworthiness. AANs were first issued in about 1945.