Please note: This use case originates from the predecessor project PJ.10-W2-73 FCA as part of the SESAR2020 Programme and is not considered in the current project.
This Use Case describes the processes which are needed regarding the VHF frequency management per Flight Centric controller in FCA taking into account the following facts.
Flight Centric airspace is considered as a wide area that is larger than a common radio frequency coverage. If several frequencies are used over such a wide area by one ATCO, the Voice Communication System (VCS) manages the use of these different frequencies and the respective antennas. If one frequency is used over such a wide area, several ground antennas have to be used for the same frequency. Therefore, the ATC controller will always hear each pilot and each pilot will always hear the ATC controller (just using different antennas, always the one closest to the respective aircraft).
Preconditions
A set of one or more frequencies is allocated to each Flight Centric EC CWP. It is named a frequency cluster and it should cover the whole FCA airspace.
VCS manages the physical frequency antennas and guarantees that the link between antennas and Flight Centric EC CWP is permanently operative.
VCS is connected to the Radar Data Processing System (RDPS) and receives flight tracks.
VCS is connected to the Flight Data Processing System (FDPS) and manages planned trajectory updates.
VCS is connected to the flight allocation system which assigns a flight to a Flight Centric EC CWP.
VCS is capable to elaborate a frequency sequence for each flight from the flight planned trajectory.
Postconditions: Success end state
The flight is on a frequency that allows two ways air-ground communication in an efficient manner.
Postconditions: Failed end state
The flight is not on a frequency that allows two ways air-ground communication in an efficient manner.
Trigger
VCS, using the current position and Flight Centric EC CWP of one flight uses the relevant frequency.
Main Flow
- VCS triggers that a frequency change needs to be performed inside the same frequency cluster and sends a message to the FCA system that the Flight Centric EC ID frequency display should be updated.
- The Flight Centric EC receives an indication on the CWP that a frequency change is needed, and the frequency change display shows the time when a CPDLC message will be automatically uploaded with no manual intervention.
- The Flight Centric EC activates the upload of the predefined CPDLC message.
- The Flight Crew acknowledges the ATC instruction to monitor the next FCA frequency via CPDLC.