The Federal Office of Civil Aviation publishes information on unapproved parts. In the aviation industry, unapproved parts are defined as aircraft parts, components, raw materials and consumables that are not manufactured, maintained or modified in accordance with the applicable regulations and international standards, or that have counterfeited certificates.
Foreign UPNs, provided they are known to the FOCA, can be accessed using the links to the appropriate supervisory authorities. UPNs that are only available to the FOCA in written form are made available for download in electronic form under the heading ‘Foreign UPNs’.
When a notification has been made, the procedures set out in the operating manuals to ensure that unapproved parts are identified and removed from parts stocks and aircraft must be strictly applied.
"Unapproved Parts Notifications" EASA and FAA