All relevant operator information, including the aircraft used for flights under the TCO authorisation, is required to be kept up-to-date during the initial application and for as long as the TCO authorisation is valid. This is normally done by the operator, using the TCO web-interface. In most circumstances, provided the information was uploaded prior to using the new aircraft, no prior approval by EASA is required for an aircraft of the same type and variant to be added to an already-authorised fleet. Should you wish to add a new aircraft type or variant (as identified by a different ICAO type designator), then prior approval from EASA must be obtained. This request needs to be submitted 30 days before the planned date of first use of the new aircraft type (TCO.315). It is at the discretion of EASA to allow selected Business Aviation operators to start operation with a new fleet without having to wait for prior approval. These operators will receive specifications for so-called “TCO Business Aircraft”, which combine aircraft of different types as long as they all meet specified criteria. Details are explained in the Annex to the TCO authorisation of the affected operators.
In general, all changes that require EASA to issue a new authorisation document or new technical specifications associated to the TCO authorisation will require prior approval by EASA.