6.5.1 Transitioning from a conventional tower to a remote tower

For the case when the service is migrated from a conventional tower to a remote tower, a transition plan should be developed and should define the different phases to be followed and the associated transition criteria, including fall-back procedures for how to revert the ATS to the conventional tower in case of unexpected events or problems. The capability of providing ATS from the conventional tower should be maintained during all transition phases, plus an additional period (to be defined by the ATS provider) following the successful migration, for contingency reasons. The transition plan should consider the following phase, as appropriate: Conventional tower control: While in this phase, ATS will be provided from the conventional tower. Transferring control: In this phase, ATS will still be provided from the conventional tower, but the necessary data will also be re-routed to the remote tower for shadow mode operations/transfer of control initiation. Remote tower control: In this phase, the responsibility for providing ATS will lie with the remote tower personnel. The transition between phases may be performed through a handover process between the conventional tower and the remote tower. This handover process should only start once the remote tower is ready to assume responsibility for the ATS. The handover protocol may be split as follows: While maintaining the provision of ATS from the conventional tower (conventional tower control phase), the remote tower ATCO/AFISO calls the conventional tower in order to declare their ability to assume responsibility for ATS. The acknowledgement of this request by the conventional tower will trigger the transition to the ‘transferring control’ phase. When all the necessary information is transferred and when all the required technical operations are completed in order to allow the remote tower system to work properly, the remote ATCO’s/AFISO’s acceptance of the responsibility will trigger the transition to the ‘remote tower control’ phases. The conventional tower unit will then inform all the other actors involved (i.e. local emergency personnel, aerodrome services, adjacent and relevant ATS units, etc.) of the successful completion of transfer of responsibility. The remote tower functional system should be designed in such a way that these phase (or equivalent ones) and the associated transitions are feasible. Additionally, the possibility to return to the ‘conventional tower control’ phase from the ‘remote tower control’ phase should be maintained throughout the transition process, and should be also maintained for some time after the successful transition for contingency reasons.