For commercial air transport of passengers, mail and cargo (CAT), an Air Operator's Certificate (AOC) and an Operating Licence are required.
Once certified, an operator is required to have any changes, e.g. to the fleet, personnel, operating principles, processes and/or documentation, reviewed by the FOCA in accordance with EASA regulations. Thereby, some changes require prior approval by the FOCA, while others only need to be notified.
Economic viability must be ensured in order to obtain and maintain an operating license.