Key Research Needs and Use Cases

This use case describes the actions to be taken to manage safe operations within FCA airspace in case of adverse weather conditions.

Preconditions

An aircraft operating under normal conditions managed by FCA ATCOs will need to modify its trajectory due to adverse meteorological conditions. One or several weather cells traverse the FCA airspace and information about their location is available for FCA tools. ATFCM related to weather are in place, e.g. halving of FCA airspace capacity.

Postconditions: Success end state

The flight deck request is granted, and the adverse weather zone is safely avoided.

Trigger

The trajectory of an aircraft inside the FCA airspace crosses an area where adverse weather conditions are in place (e.g. thunderstorm).

The system identifies an aircraft crossing an adverse weather zone – Main Flow

1. The CD&R tool identifies the aircraft on track towards an adverse weather zone.
2. The CD&R tool calculates a conflict-free avoidance route and provides a visual identification to the FCA ATCO.
3. The FCA ATCO evaluates the weather avoidance maneuver. No coordination with other ATCOs is needed.
4. The FCA ATCO activates the avoidance maneuver.
5. The FCA ATCO  issues an ATC clearance (e.g. level change, direct to, heading) to the flight deck and enters this instruction into the FDPS simultaneously.
6. The flight deck executes the ATC clearance by modifying the trajectory, i.e., updates the FMS.

The flight deck identifies an adverse weather zone ahead – Main Flow

1. The flight deck identifies the adverse weather zone and contacts the FCA ATCO to request an avoidance maneuver.
2. The FCA ATCO evaluates different weather avoidance maneuvers. No coordination with other ATCOs is needed.
3. The FCA ATCO activates the avoidance maneuver, issues an ATC clearance (for example level change, direct to, heading) to the flight deck and enters this instruction into the FDPS simultaneously.
4. The flight deck executes the ATC clearance by modifying the trajectory, i.e., updates the FMS.

The flight deck identifies an adverse weather zone ahead – Alternate Flow

Step 1 is the same as in the main flow.

2. The FCA ATCO evaluates different weather avoidance manoeuvres. Coordination with other FCA ATCOs is needed.
3. The FCA ATCO in charge of the flight that must perform a weather avoidance manoeuvre coordinates with the FCA ATCOs involved in order to avoid potential conflicts.
4. When the new trajectory is clear of potential conflicts the FCA ATCO activates the avoidance manoeuvre, issues an ATC clearance (for example level change, direct to, heading) to the flight deck and enters this instruction into the FDPS simultaneously.
5. The flight deck executes the ATC clearance by modifying the trajectory, i.e., updates the FMS.

This use case describes how a military flight entering and transiting through the FCA airspace is controlled.

Precondition

Military aircraft is going to enter the FCA airspace.

Postconditions: Success end state

Military flight has safely passed through the FCA airspace and is handed over to the next ATC unit.

Trigger

The allocation system receives information from the military aircrfat about to enter FCA airspace.

Military aircraft entering an ARES within the FCA airspace – Main Flow

1. The allocation system allocates the military flight aircraft to the/an FCA MIL ATCO. The frequency of the FCA MIL ATCO is indicated to the upstream controller.
2. The military flight deck performs the initial call, informing the FCA MIL ATCO about its status and intentions.
3. The FCA MIL ATCO reciprocates the initial call and assumes responsibility for the military flight aircraft.
4. The FCA MIL ATCO guides the military aircraft through the FCA airspace, maintaining separation to civil aicraft(which have the right-of-way).
5. When the military aircraft reaches the ARES entry point, the FCA MIL ATCO hands over the aircraft to Air Defence.

Military aircraft entering an ARES within the FCA airspace – Alternate Flow

Steps 1 to 3 are the same as in the main flow.

4. The FCA MIL ATCO detects a conflict indication and has conflict resolution responsibility as civil aircraft have the right-of-way.
5. The FCA MIL ATCO previews and activates the conflict resolution suggested by the CD&R tool to ensure separation to civil aircraft.
6. The FCA MIL ATCO issues the necessary ATC clearances to the military flight deck to solve the potential conflict.
7. The military flight deck executes the ATC clearance by modifying the trajectory.
8. When the military aircraft reaches the ARES entry point, the FCA MIL ATCO hands over the aircraft to Air Defence.

Military aircraft exiting an ARES within the FCA airspace – Main Flow

1. The allocation system allocates the military aircraft to the/an FCA MIL ATCO. The frequency of the FCA MIL ATCO is indicated to Air Defence.
2. Air Defence coordinates entry of military aircraft into FCA airspace with FCA MIL ATCO via telephone.
3. The military flight deck performs the initial call, informing the FCA MIL ATCO about its status and intentions.
4. The FCA MIL ATCO reciprocates the initial call and assumes responsibility for the military aircraft.
5. The FCA MIL ATCO guides the military aircraft through the FCA airspace, maintaining separation to civil aicraft(which have the right-of-way).When the military aircraft is close to reaching the adjacent ATC unit, the FCA MIL ATCO hands over the aircraft.

Military aircraft exiting an ARES within the FCA airspace – Alternate Flow

Steps 1 to 4 are the same as in the main flow.

5. The FCA MIL ATCO detects a conflict indication and has conflict resolution responsibility as civil aircraft have the right-of-way.
6. The FCA MIL ATCO previews and activates the conflict resolution suggested by the CD&R tool to ensure separation to civil aircraft.
7. The FCA MIL ATCO issues the necessary ATC clearances to the military flight deck to solve the potential conflict.
8. The military flight deck executes the ATC clearance by modifying the trajectory.
9. When the military aircraft is close to reaching the adjacent ATC unit, the FCA MIL ATCO hands over the aircraft.

The following Use Case describes the ground-ground coordination between FCA ATCO, in charge of flights within FCA airspace, and non-FCA ATCO, in charge of flights outside FCA airspace.

Precondition

A flight is going to enter or exit the FCA airspace, where transfer procedures and conditions are established.

Postconditions: Success end state

Change request (from pilots or non-FCA ATCO) is coordinated and agreed and new trajectory is applied.

Trigger

Request from pilots or non-FCA ATCO (for example for level change) to a FCA ATCO.

Request from an aircraft operating inside FCA airspace – Main Flow

1. The FCA ATCO receives a request (for example a re-routing) from one pilot.
2. The FCA ATCO assesses the situation, and communicates via voice (by telephone, elbow or hotline) or electronic coordination with the downstream non-FCA ATCO
3. The non-FCA ATCO assesses if the request is free of conflicts. The request is free of conflicts and the non-FCA ATCO communicates it via voice (by telephone, elbow or hotline) with the FCA ATCO. .
4. FCA ATCO gives the clearance for addressing the request and introduces the change into the FDPS simultaneously.
5. Flight Crew executes the ATC clearance and updates the FMS.
6. FCA ATCO transfers the flight to non-FCA ATCO.

Request from an aircraft operating inside FCA airspace – Alternate Flow

Steps 1 and 2 are the same as in the main flow.

3. The non-FCA ATCO assesses if the request is free of conflicts. The request is not free of conflicts.
4. The non-FCA ATCO cannot accept the request as it is;
5. The non-FCA ATCO needs to amend the request or make some changes in his/her traffic or make additional coordination, before he/she can approve the request.
6. When the request is free of conflicts, the non-FCA ATCO accepts the request and communicates it to FCA ATCO via voice (by telephone, elbow or hotline).
7. FCA ATCO gives the clearance, thus addressing the request, and introduces the change into the FDPS simultaneously.
8. Flight Crew executes the ATC clearance and updates the FMS.
9. FCA ATCO transfers the flight to non-FCA ATCO.

Request from a non-FCA ATCO in charge of an aircraft inbound the FCA airspace – Main Flow

1. The non-FCA ATCO sees in the label which is the FCA ATCO that will be next responsible for the aircraft.
2. The non-FCA ATCO contacts via Voice Communication System (VCS, by telephone, elbow or hotline) or electronic coordination, with the FCA ATCO and communicates the aircraft’s request.
3. The FCA ATCO checks if the situation is free of conflicts.
4. The situation is free of conflicts and the FCA ATCO informs about it to the non-FCA ATCO.
5. Non-FCA ATCO provides the clearance, thus addressing the request, and introduces the change into the FDPS simultaneously.
6. Flight Crew executes the ATC clearance and updates the FMS.
7. Non-FCA ATCO transfers the flight to FCA ATCO.

Request from a non-FCA ATCO in charge of an aircraft inbound the FCA airspace – Alternate Flow

Steps 1 to 3 are the same as in the main flow.

4. The situation is not free of conflicts and the request has to wait until it is free of conflict.
5. The FCA ATCO informs the non-FCA ATCO about the situation and both monitor the situation and coordinates necessary actions to avoid the conflict.
6. The situation is free of conflicts and the FCA ATCO informs about it to the non-FCA ATCO.
7. Non-FCA ATCO provides the clearance, thus addressing the request, and introduces the change into the FDPS simultaneously.
8. Flight Crew executes the ATC clearance and updates the FMS.
9. Non-FCA ATCO transfers the flight to FCA ATCO.

Request from a non-Flight Centric ATCO in charge of an aircraft not initially inbound the FCA airspace, but requesting to penetrate the FCA area – Main Flow

1. The non-FCA ATCO communicates via VCS with the Allocator to ask which FCA ATCO is the appropriate one to coordinate the request.
2. The Allocator evaluates the situation with the allocator supporting tool and tells the non-FCA ATCO which FCA ATCO he/she should contact, thus allocating the affected aircraft to a certain FCA ATCO.
3. The non-FCA ATCO contacts via VCS or electronic coordination with the designed FCA ATCO and communicates the aircraft’s request.
4. The FCA ATCO checks if the situation is free of conflicts.
5. The situation is free of conflicts and the FCA ATCO informs via VCS or electronic coordination about it to the non-FCA ATCO.
6. Non-FCA ATCO gives the clearance for addressing the request and introduces the change into the FDPS simultaneously.
7. Flight Crew executes the ATC clearance and updates the FMS.
8. Non-FCA ATCO transfers the flight to FCA ATCO.

Request from a non-Flight Centric ATCO in charge of an aircraft not initially inbound the FCA airspace, but requesting to penetrate the FCA area – Alternate Flow

Steps 1 to 4 are the same as in the main flow.

5. The situation is not free of conflicts and the request has to wait until it is free of conflict.
6. The FCA ATCO informs the non-FCA ATCO (via voice or electronical coordination) about the situation and both monitor the situation.
7. The situation is free of conflicts and the FCA ATCO informs about it to the non-FCA ATCO.
8. Non-FCA ATCO gives the clearance for addressing the request and introduces the change into the FDPS simultaneously.
9. Flight Crew executes the ATC clearance and updates the FMS.
10. Non-FCA ATCO transfers the flight to FCA ATCO.

This use case is identified to describe decision-making process in DCB process from strategic to tactical phase for FCA airspace.

Specific assumptions

• At the first stage, NM defines DCB processes and methods for FCA operations at Network level.
• Secondly, each ANSP, is in charge of the local implementation of the defined DCB processes and methods. Main phases are:
  • Strategic (until D-7)
  • Pre-tactical (D-6 to D-1)
  • Tactical (D-0)
• On strategic phase each ANSP decides on how to organize the DCB service provision. The ANSP ATFCM Unit, this actor is in charge of DCB tasks in strategic & pre-tactical timeframes, giving the elaboration of an appropriated configurations plan.
• At each ACC, there is the Local Traffic Manager (LTM) that acts on tactical phases adjusting.

Precondition

Demand prediction is available.
The airspace design is available including the definition of FCA airspace.

Postconditions

Flights are assigned to FCA positions, while the Airstreams are managed by Airstream Manager, and are a segregated airspace not part of the FCA airspace.

Trigger

Months before operation day, ANSP receives traffic predictions and initiates DCB process in order to plan ATC resources.

Main Flow

1. During the strategic phase (months before operation and up to seven days before operation), the ANSP ATFCM Unit, using traffic predictions, asses the FCA configuration plan, which identifies the number of FCA positions to be opened during the day, considering the expected demand inside the FCA.
2. During the pre-tactical phase (from six days before operation, until one day before operation day), ANSP ATFCM Unit):

• Refines the configuration plan for the FCA airspace considering the complexity of the available latest prediction of the expected demand for FCA airspace.
• Prepares the different DCB measures available such as re-routings and level capping scenarios, regulations, cherry picking, etc.

3. During tactical phase, Supervisor:

• At the start of every shift, reviews the configuration plan and confirms enough FCA ATCOs are available. Adjusts planning if not enough FCA ATCOs are available.
• Coordinates permanently with LTM (if needed) every measure needed to fulfil DCB plan and leads the execution of the plan.

4. During tactical phase (on operation day up to 2 hours in advance to operation time), LTM:

• monitors the traffic demand and the complexity predicted for each FCA position, and in case of deviations from the expected scenario, coordinates with supervisor and refines configuration plan for FCA, and  prepares and implements ATFCM measures.
• monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. He/she assures that the FCA capacity is not exceeded.

5. During tactical phase (on operation day from 2 hours to 20 minutes in advance to operation time), LTM:

• Monitors the traffic demand and helps to dynamically update operational room configuration in coordination with supervisor.
• Implements short-term tactical measures such as level capping or early descend to reduces traffic complexity.
• Monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. He/she assures that the FCA capacity is not exceeded.

6. During tactical phase (on operation day from 20 minutes to 5 minutes before FCA entry time), Allocator:

• In FCA area context, the Allocator, accompanied by their decision supporting tool (which updates the network situation and configuration plan taking into consideration the current traffic flying inside the FCA airspace and future traffic that will entry in a window of 20 minutes) monitors the allocation and configuration plan.
• Monitors the traffic demand
• During an opening or closure of an FCA position, they are the responsible for the final traffic  allocation between FCA positions.
• Monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. They assure that the FCA capacity is not exceeded.
• The Allocator ensures that the established configuration plan and allocation is the optimal according to the traffic characteristics. If true, the Allocator does not apply any change.

Alternate Flow 1

Step 1-3 are the same than in main flow.

4. During tactical phase (on operation day up to 2 hours in advance to operation time), LTM:

• Monitors the traffic demand and the complexity predicted for each FCA position, and in case of deviations from the expected scenario, coordinates with supervisor and refines configuration plan for FCA, and/or  prepares and implements ATFCM measures.
• Monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. He/she observes that the  FCA capacity is exceeded.

5. LTM applies ATFM measures to ensure that FCA ATCOs workload are within adequate levels.
6. If needed, affected Airspace Users updates their flight plans.
7. During tactical phase (on operation day from 2 hours to 20 minutes in advance to operation time), LTM:

• Monitors the traffic demand and helps to dynamically update operational room configuration in coordination with supervisor.
• Implements short-term tactical measures such as level capping or early descend to reduces traffic complexity.
• Monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. He/she assures that the FCA capacity is not exceeded.

8. During tactical phase (on operation day from 20 minutes to 5 minutes before FCA entry time), Allocator:

• In FCA area context, the Allocator, accompanied by his/her decision supporting tool (which updates the network situation and configuration plan taking into consideration the current traffic flying inside the FCA airspace and future traffic that will entry in a window of 20 minutes) monitors the allocation and configuration plan.
• In FCA area context, the Allocator, accompanied by their decision supporting tool (which updates the network situation and configuration plan taking into consideration the current traffic flying inside the FCA airspace and future traffic that will entry in a window of 20 minutes) monitors the allocation and configuration plan.
• Monitors the traffic demand
• During an opening or closure of an FCA position, they are the responsible for the final traffic  allocation between FCA positions.
• Monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. They assure that the FCA capacity is not exceeded.
• The Allocator ensures that the established configuration plan and allocation is the optimal according to the traffic characteristics. If true, the Allocator does not apply any change.

Alternate Flow 2

Steps 1-4 are the same than in the main flow:

5. During tactical phase (on operation day from 2 hours to 20 minutes in advance to operation time), LTM:

• Monitors the traffic demand and helps to dynamically update operational room configuration in coordination with supervisor.
• Implements short-term tactical measures such as level capping or early descend to reduces traffic complexity.
• Monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. He/she observes that the FCA capacity is exceeded.

6. LTM applies necessary measures to keep FCA traffic demand under defined thresholds to not exceed capacity, opening/closing FCA positions, applying short-term tactical measures.
7. During tactical phase (on operation day from 20 minutes to 5 minutes before FCA entry time), Allocator:

• In FCA area context, the Allocator, accompanied by his/her decision supporting tool (which updates the network situation and configuration plan taking into consideration the current traffic flying inside the FCA airspace and future traffic that will entry in a window of 20 minutes) monitors the allocation and configuration plan.
• In FCA area context, the Allocator, accompanied by his/her decision supporting tool (which updates the network situation and configuration plan taking into consideration the current traffic flying inside the FCA airspace and future traffic that will entry in a window of 20 minutes) monitors the allocation and configuration plan.
• In FCA area context, the Allocator, accompanied by their decision supporting tool (which updates the network situation and configuration plan taking into consideration the current traffic flying inside the FCA airspace and future traffic that will entry in a window of 20 minutes) monitors the allocation and configuration plan.
• Monitors the traffic demand
• During an opening or closure of an FCA position, they are the responsible for the final traffic  allocation between FCA positions.
• Monitors if the overall workload for the FCA airspace applied in the configuration plan keeps inside the defined thresholds. They assure that the FCA capacity is not exceeded.
• The Allocator ensures that the established configuration plan and allocation is the optimal according to the traffic characteristics. If true, the Allocator does not apply any change.

Alternate Flow 3

Step 1-5 are the same than in main flow.

6. The Allocator ensures that the established configuration plan and allocation is the optimal according to the traffic characteristics. If it is not true, the Allocator with help of his/hers support tool sees that workload balance is over the threshold for some position and applies a correction method, re-allocating flight/s (See Use Case 1) to keep workload within acceptable levels.

This use case describes the actions to be taken to opening a new FCA position or closing an existing FCA position.

Precondition

Too high or too low ATCO workload are identified, so it is convenient to open or close a FCA position. For opening a new position, enough controllers are available.  

Postcondition:

The opening/closure of a new FCA position and the reallocation of the correspondent traffic have been correctly done.

Trigger

The allocator monitors continuously the Entry Hourly Rate, Occupancy Counts and Complexity indicators in the Allocation Supporting Tool. When the prediction is out of the defined thresholds (superior or inferior), then the situation is suitable for opening/closing a FCA position, so he/she informs the supervisor to initiate the procedure.

Position opening – Main Flow

1. The Allocator assess with the allocation supporting tool the traffic distribution and decides the optimal traffic allocation after the opening of an FCA position.
2. The Allocator coordinates with the Supervisor (in case the Allocator is a different actor) the opening of an FCA position after having analysed the current and entering traffic to the FCA airspace.
3. The Allocator confirms, enough time in advance, the new traffic distribution among the final positions and expected to be applied in the operational room as well as the related frequencies.
4. The Allocator coordinates with all the ATCOs involved the aircraft that will be assigned to them.
5. All FCA ATCOs are able to see in their HMI the current and future situation at the same time and start the coordination via voice or electronically with their flights to ensure a safe procedure.
6. The Allocator gives the order to open a position through the system after the ATCOs confirm they have coordinated all relevant flights and state they are ready for the position opening.
7. At the moment of the opening, all the involved traffic in FCA position changing (could be entering traffic or existing traffic inside the FCA) will be automatically transferred by the system to its new position according to the decided traffic distribution.
8. The involved FCA ACTOs confirm that all expected traffic under their responsibility is well assigned to them.

Position closure – Main Flow

1. The Allocator assess with the allocation supporting tool the traffic distribution and decides the optimal traffic allocation after the closure of an FCA position.
2. The Allocator coordinates with the Supervisor (in case the Allocator is a different actor) the closure of an FCA position after having analysed the current and entering traffic to the FCA airspace.
3. The Allocator confirms, enough time in advance, the new traffic distribution among the final positions and expected to be applied in the operational room as well as the related frequencies.
4. The Allocator coordinates with all the ATCOs involved the aircraft that will be assigned to them.
5. All FCA ATCOs are able to see in their HMI the current and future situation at the same time and start the coordination via voice or electronically with their flights to ensure a safe procedure.
6. The Allocator gives the order to close a position through the system after the ATCOs confirm they have coordinated all relevant flights and state they are ready for the position closure.
7. At the moment of the closing, all the traffic entering and existing into the FCA will be automatically transferred by the system to its new position according to the decided traffic distribution.
8. The involved FCA ATCOs confirm that all expected traffic under their responsibility is well assigned to them.

This use case describes how incoming traffic is allocated to the FCA ATCOs considering rule based dynamic allocation, automated or semi-manual, which aims to keep the workload balanced between all positions and within acceptable levels.

The threshold workload defined to establish the capacity of FCA is defined taken into account airspace complexity, the complexity of the traffic and the number of needed ATCOs.

Precondition

Aircraft is going to enter the FCA airspace.

Postconditions: Success end state

Aircraft is allocated to one FCA ATCO according to the selected allocation strategy.

Workload of each FCA ATCO is maintained at acceptable levels.

Trigger

1. Approximately 20 minutes before an aircraft enters the FCA airspace the FDPS receives and distributes information about the incoming aircraft.
2. The Allocator with help of their supporting tool is monitoring traffic allocation and sees that  workload is over the threshold for some position and applies a correction method,  re-allocating  incoming flight/s (See Alternate Flow 3 from Use Case 4) to keep workload within acceptable levels.
3. One FCA ATCO ask the Allocator to reallocate one of their flights because they are overloaded. The Allocator applies correction method,  re-allocating  flight/s already inside FCA airspace to keep workload within acceptable levels.
4. An unplanned traffic request to enter FCA airspace and Allocator should allocate the flight to an FCA ATCO (see UC 3 Flow 3).

Dynamic and automatic traffic allocation – Main Flow

1. The allocation system determines the workload that the aircraft is predicted to add to a controller  based on factors such as vertical movements and potential conflicts predicted within the FCA airspace.
2. The allocation system allocates the aircraft to an FCA ATCO so that the workload among all FCA ATCOs is kept balanced and within acceptable levels.
3. The information regarding the allocation (the controller/frequency the aircraft is allocated to is made available to the upstream non-FCA ATCO through the FDPS (for example Sysco/OLDI), dedicated service or IOP as per IOP specifications defined in SESAR 1. The information about the allocation of the aircraft is also distributed to the respective FCA ATCO.

Dynamic and semi-manual traffic allocation – Main Flow

1. The allocation system determines the expected workload that each incoming aircraft will add, based on factors such as expected vertical movements and expected number of potential conflicts, everything predicted within the FCA airspace.
2. The allocation system allocates the aircraft to an FCA ATCO so that the workload (defined as complexity, which is the measure of the difficulty that a particular traffic situation will present to an ATCO) among all FCA positions is kept balanced and within acceptable levels.
3. The information regarding the allocation is made available to the Allocator, upstream non-FCA ATCO and FCA ATCO through the FDPS.
4. The Allocator analyzes the situation with the help of the Allocator support tool so he/she can monitor constantly the workload of the positions to control up to 5 minutes before the aircraft entries the FCA airspace, moment from which the aircraft are definitely allocated.
5. The workload balance is kept under upper threshold in every position, so the Allocator doesn´t take any action thus validating the allocation.

Dynamic and semi-manual traffic allocation – Alternate Flow 1

Steps 1 to 4 are the same as in the main flow.

5. The workload balance is not kept under upper threshold in one position, so the Allocator takes action.
6. The Allocator analyzes the situation, with the help of the allocator support tool, and re-allocates an aircraft from the affected position to another FCA position, so both positions will be at acceptable levels.
7. The Allocator applies the new allocation.
8. The information regarding the allocation is made available again through the FDPS to the Allocator, upstream non-FCA ATCO and FCA ATCO.

Dynamic and semi-manual traffic allocation – Alternate Flow 2

Steps 1 to 5 are the same as in the main flow.

6. An FCA ATCO communicates to the Allocator that is overloaded. A reallocation of their flights is needed.
7. Allocator analyses the situation inside FCA airspace in order to fix the unbalance and applies measures to correct it.
8. Allocator coordinates with the affected FCA ATCOs the reallocation of flights.

This use case describes the detection and resolution of conflicts within the FCA airspace managed by several FCA ATCOs working in SPO, who have a CD&R tool available. The conflict occurs between two  aircraft controlled by different ATCOs. The conflict appears before an STCA is triggered, otherwise the procedure described in section 3.3.2.1.9 must be followed.

Precondition

Two aircraft under the responsibility of different ATCOs have conflicting trajectories.

Postconditions: Success end state

The trajectories are no longer conflicting. The warning is no longer displayed.

Trigger The CD&R tool detects conflicting trajectories between two aircraft and a warning is shown to the involved FCA ATCOs.

CD&R equipped with less impacted flight algorithm involving imminent and non-imminent conflicts – Main Flow

1. The CD&R tool detects a conflict between two aircraft. Both aircraft are inside the FCA airspace. The CD&R tool based on the LIFA algorithm and defined rules determines which aircraft needs to give way. The FCA ATCO controlling the aircrafthas the responsibility to solve the conflict.
2. The conflict warning and conflict responsibility are indicated by colour to the involved FCA ATCOs. Furthermore, a conflict resolution proposal is indicated to the FCA ATCO who must solve the conflict.
3. The FCA ATCOs assess the conflict situation.
4. The FCA ATCO who is responsible for conflict resolution assesses the conflict resolution proposed by the CD&R tool.
5. The FCA ATCO issues an ATC clearance (e.g. level change, direct to, heading) to the Flight Deck and updates the flight plan data in the system simultaneously
6. The Flight Crew executes the ATC clearance by modifying the trajectory, i.e., updates the FMS and conflict is resolved.

CD&R equipped with less impacted flight algorithm involving imminent and non-imminent conflicts – Alternate Flow

1. The CD&R tool detects a conflict between two aircraft. One aircraft inside the FCA airspace and the other is outside. The CD&R tool (with the less impacted flight algorithm) assigns conflict resolution responsibility to the Flight Centric ATCO, based on the rule that the FCA ATCO must have conflict responsibility in case one of the conflicting aircraft is outside of the FCA airspace.

Steps 2 to 6 are the same as in the main flow.

Solving non-imminent conflict without less impacted flight algorithm – Main Flow

1. The conflict detection tool detects a problem between two aircraft. Both aircraft are inside FCA airspace.
2. The tool alerts the FCA ATCOs involved.
3. FCA ATCOs involved assess the validity of the shown conflict.
4. FCA ATCOs involved coordinate and agree on a solution and will share responsibility of solving the conflict.
5. FCA ATCO(s) (one or both) execute the agreed conflict resolution  by issuing an ATC clearance and updates the FMS.
6. The Flight Crew implements the ATC instruction and updates the FMS.

Solving non-imminent conflict without less impacted flight algorithm – Alternate Flow

1. The conflict detection tool detects a conflict between two aircraft. One aircraft is inside the FCA airspace, and the other aircraft is outside.
2. The conflict detection tool alerts the FCA ATCO and the non-FCA ATCO involved in the conflict.
3. FCA ATCO and the non-FCA ATCO involved in the conflict assess the criticality of the shown conflict.
4. FCA ATCO and/or non-FCA ATCO execute the agreed conflict resolution by issuing an ATC clearance and updates the FMS. The FCA ATCO and/or the non-FCA ATCO issues an ATC clearance (for example level change, direct to or heading) to the Flight Deck, and simultaneously enters this instruction into the FDPS.
5. The Flight Crew implements the ATC clearance, and consequently updates the FMS.

Solving an imminent conflict by vertical evasive manoeuvres – Main Flow

1. The iCD&R tool detects an imminent conflict between two aircraft.
2. The iCD&R tool determines, based on an algorithm and defined rules, a resolution proposal to ATCOs involved in the conflict by suggesting vertical evasive manoeuvres to aircraft involved. Both aircraft are inside the FCA airspace.
3. Both FCA ATCOs involved in the conflict quickly assess the validity of the shown conflict and the proposed solution.
4. FCA ATCOs issue clearances to affected aircraft, aligned with the solution proposal issued by the iCD&R tool and enter this instruction into the FDPS simultaneously.
5. The Flight Crew executes the ATC clearance and updates the FMS.

Solving an imminent conflict by vertical evasive manoeuvres – Alternate Flow

Steps 1 is the same as in the main flow.

2. The iCD&R tool determines, based on an algorithm and defined rules, a resolution proposal to ATCOs involved in the conflict by suggesting vertical evasive manoeuvres to aircraft involved. One aircraft is inside the FCA airspace, and the other is outside.
3. The ATCOs involved in the conflict (FCA and non-FCA) assess the validity of the shown conflict and the proposed resolutions.
4. The ATCO which is assigned an action issue the ATC clearance proposed by the iCD&R tool to the Flight Deck and enter this instruction into the FDPS simultaneously.
5. The Flight Crew executes the ATC clearance and updates the FMS.

This use case describes the actions to be taken in an FCA airspace in case of a loss of communication with an aircraft.

Precondition

An aircraft is assigned to an FCA ATCO and has been assumed. Air-ground communication is established.

Postconditions: Success end state

The aircraft has safely left the FCA airspace.

Trigger

An aircraft inside the FCA airspace experiences a radio failure.

Main Flow

1. The FCA ATCO has tried multiple times to contact the flight deck via radio communication with no success. He/she manually sets the affected aircraft on “communication failure” status by setting a flag in the aircraft’s label.
2. The aircraft’s “communication failure” status is shared and notified to all other FCA ATCOs and the FCA Supervisor through the ATM System.
3. The FCA ATCO informs the downstream ATCO about the situation.
4. All FCA ATCOs ensure that all aircraft under their responsibility that might be affected by the aircraft with communication failure are out of the way. Whenever this aircraft has a conflict with another aircraft in the FCA airspace under control of a different FCA ATCO, the conflict responsibility is assigned to the other FCA ATCO who solves the conflict, following the methodology established on UC2.

Alternate Flow 1

1. The flight deck identifies the radio failure and squawks 7600. The ATM system automatically sets a “communication failure” flag in the aircraft’s label.
2. The aircraft’s “communication failure” status is automatically shared and notified to all FCA ATCOs and the FCA Supervisor.
3. The flight deck maintains the assigned speed and level for a period of 7 minutes after realizing their communication failure status and thereafter adjusts level and speed in accordance with the filed flight plan (ICAO Annex 2 Rules of the Air chapter 3.6.5.2.2).

Steps 4 is the same as in the main flow.

This use case describes the actions to be taken in an FCA airspace in case a short-term conflict alert occurs.

Preconditions

Two aircraft are on converging trajectories in a timeframe of around 5 to 2 minutes.

Post conditions: Success end state

A Short-term avoidance maneuvers have been conducted and the two aircraft are clear of conflict. The warning is no longer displayed.

Trigger

A short-term conflict alert is shown to the FCA ATCOs.

Main Flow

1. The short-term conflict alert is shown to the different FCA ATCOs. The short-term conflict responsibility is clearly defined by procedures.
2. The FCA ATCO  responsible to take action over this short-term conflict immediately issues an instruction (avoidance maneuver). He/she monitors the resolution of the conflict. No coordination between the two involved Flight Centric ATCOs takes place.

Alternate Flow

Step 1 is the same as in the main flow.

2. The Flight Centric ATCO should not take action over this short-term conflict. He/she monitors the resolution of the conflict.

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 actions to be taken for activating the Flight Centric Area. There are two modes for the transition/switch from sectored ATC to Flight Centric ATC operations:

• Alternating system mode: Two different controller teams control in conventional ATC and FCA. There are also two different CWP platforms (equipment) for the different modes.
• Remodelling system mode: The same controller team controls in both conventional ATC and FCA. The CWP platform is prepared to change the mode in the same system.

Preconditions

Parameters or time is fulfilled to change from sectored ATC to Flight Centric ATC.
Parameters should be set or overall capacity/complexity for defined portion of airspace. This parameter is used for decision making whether the FCA mode of operation is applicable/useful in a certain portion of airspace for a certain period of time.

Postconditions: Success end state

Flight Centric ATC mode of operation is applied in the defined airspace.

Postconditions: Failed end state

Flight Centric ATC mode of operation is not applied in the defined airspace.

Trigger

Local FMP monitors continuously the Entry Hourly Rate, Occupancy Counts and Complexity indicators in the Local Traffic Management Tool (Complexity Management Tool) in the airspace predefined for FCA operations. When the prediction is out of the defined thresholds and suitable for activation of the FCA operations he informs the Supervisor in order to initiate the transition/switch procedure.

Main Flow

Alternating system mode

1. The Supervisor, Local Traffic Manager, PC with EAP role (depends on local implementation) monitor the expected workload per trajectory.
2. The Local Traffic Manager, Supervisor and PC with EAP role (depends on local implementation) analyse the situation and decide that the FCA preconditions are met and prepare to activate a predefined scenario to dynamically switch from conventional ATC to FCA operation in a specified portion of airspace as a solution for the detected imbalance.
3. The Supervisor confirms to activate the Flight Centric Area at least 20 minutes in advance and the allocation support function is activated. In case the Allocator is not performed by the Supervisor he starts to work.
4. The Allocation support function analyses automatically (shadow mode) the traffic situation and indicates the traffic expected to be transferred to the Flight Centric controllers to the Supervisor and Allocator (in case if not performed by the Supervisor);
5. Based on the information presented by the Allocation support function, the Supervisor decides about the required number of FCA positions (with the respective frequencies to be used) and which sectors (and parts of sectors, in case the vertical profile of the sectors is changed) will be transferred/switched into a Flight Centric Area. In case an Allocator is available the Supervisor coordinates with the Allocator;
6. In automatic allocation the Supervisor or Allocator (if not performed by the Supervisor) reviews and decides if whether to override the automatic allocation. In semi manual allocation the Supervisor or Allocator (if not performed by the Supervisor) revises the information of the allocation support function and may change it if needed;
7. The Allocator (if not performed by the Supervisor) and/or Supervisor informs each of the conventional EC/PC teams about the new FCA and sector configuration, the frequencies of the FCA positions (the EC/PC teams in the airspace volume that will remain in conventional sectored mode can keep their original frequencies) and the traffic expected to be transferred to the FCA positions as well as conventional sector positions;
8. The Allocator (if not performed by the Supervisor) and/or Supervisor informs the Flight Centric ECs and PC(s) about the allocation strategy (dynamic or static) that will be applied and the traffic that will be transferred to their positions from the current conventional sectors as well as the respective FCA frequencies;
9. Before Flight Centric Area activation (time horizons depend on local conditions), FCA controllers can analyse the traffic situation on their CWP (shadow mode) and if they have any doubt about the traffic situation, they can contact via hotline the corresponding controllers to clarify the problem and keep situational awareness.
10. The Supervisor activates the new airspace configuration that includes the Flight Centric Area;
11. As soon as possible, following the activation of the new airspace configuration, the impacted EC and PC conventional controllers transfer the identified flights to the new FCA positions and/or to conventional sector positions;
12. All involved controllers confirm to the Supervisor that all expected traffic have been received.

Alternate flow

Remodeling system mode

Steps 1 to 6 are the same as in the Main Flow.

7. The Supervisor and/or Allocator (if not performed by Supervisor) informs the controller team and in case more controllers are required in FCA operations the new FCA controllers about

• the new roles (Flight Centric EC/PC team, which Flight Centric PC(s) supports which Flight Centric ECs or SPO),
• the new airspace configuration in the Flight Centric Area (airspace and team composition) and in conventional sectors area (airspace and sector configuration),
• the allocation strategy (dynamic or static) that will be applied in FCA,
• the traffic that will be transferred to them from the current conventional sectors and
• the new FCA frequencies if more controllers are required (the original ECs maintain the original frequencies).

8. Before Flight Centric Area activation (time horizons depend on local conditions) all controllers (if more controllers are required in FCA configuration) can analyse the traffic situation in their CWP (shadow mode), in two different options:

• Visualize the shadow mode in the same screen when holding or clicking a button;
• Visualize the shadow mode in an additional screen when the Supervisor has communicated the switch;

and if they have any doubt about the traffic situation of other flights not assumed by them, but which will be under their responsibility after the switch, they can contact via hotline the corresponding controllers to clarify the problem and keep situational awareness. If new controllers are needed, they will be able to maintain the situational awareness and ask questions from their CWP in shadow mode (since they are not controlling).

9. The Supervisor activates the new airspace configuration that includes the Flight Centric Area;
10. As soon as possible, following the activation of the new airspace configuration, the impacted EC and PC conventional controllers transfer the identified flights to other FCA positions and/or to other sectors and the remaining flights stay with the same controller (some now as FCA controller).
11. All involved controllers confirm to the Supervisor that all expected traffic have been received.

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 actions to be taken for changing from FCA to sectored ATC.

There are two modes for the transition/switch from Flight Centric ATC to sectored ATC operations:

• Alternating system mode: Two different controller teams control in conventional ATC and FCA. There are also two different CWP platforms (equipment) for the different modes.
• Remodelling system mode: The same controller team controls in both conventional ATC and FCA. The CWP platform is prepared to change the mode in the same system.

Preconditions

Parameters or time are fulfilled to change from Flight Centric ATC to sectored ATC.

Postconditions: Success end state

Conventional mode of operation is applied in the defined airspace.

Postconditions: Failed end state

Conventional mode of operation is not applied in the defined airspace. Flight Centric mode of operations remains active.

Trigger

Local FMP monitors continuously the Entry Hourly Rate, Occupancy Counts and Complexity indicators in the Local Traffic Management Tool (Complexity Management Tool) in the airspace predefined for FCA operations. When the prediction is out of the defined thresholds and suitable for activation of the conventional sectored operations, he informs the supervisor in order to initiate the transition/switch procedure.

Main Flow

Alternating system mode

1. The Local FMP coordinates with the Supervisor the deactivation of the Flight Centric Area returning to conventional sector configurations;
2. The Supervisor confirms, at least 20 minutes in advance, the conventional sector configuration expected to be applied in the operational room as well as the related frequencies;
3. The Supervisor (could also be performed by the Allocator) analyses the traffic situation and informs the Allocator (in case the Allocator is an own actor) about the traffic expected to be transferred to the new conventional sectors. In case Supervisor and Allocator are performed by the same actor, then he analyses the traffic situation through the allocation support function (shadow mode); The shadow mode can be shown in two different options:

• Visualize the shadow mode in the same screen when holding or clicking a button.
• Visualize the shadow mode in an additional screen.

4. The Supervisor informs each of EC and PC from FCA and non-FCA positions about the new sector configuration expected to be applied and the new related frequencies as well as the traffic expected to be transferred to other positions;
5. Before the activation of new airspace configuration (time horizons depend on local conditions), the non-FCA controllers that were not working when the FCA was opened, can analyse the traffic situation in their CWP (shadow mode) and if they have any doubt about the traffic situation, they can contact via hotline the corresponding controllers to clarify the problem and keep situational awareness;
6. Supervisor activates the new airspace configuration with conventional sectors and Allocation support function is disconnected. In case the Allocator is not performed by the Supervisor he stops to work;
7. As soon as possible, the impacted Flight Centric EC and PC controllers transfer the identified flights to the new conventional positions;
8. All involved controllers confirm to the Supervisor that all expected traffic have been received.

Alternate flow

Remodeling system mode

Steps 1 to 2 are the same as in the Main Flow.

3. The Supervisor (could also be performed by the Allocator) analyses the traffic situation through the allocation support function (shadow mode) which shows the traffic expected to be transferred to the new conventional sectors and informs the Allocator in case the Allocator is an own actor. The shadow mode can be shown in two different options:

• Visualize the shadow mode in the same screen when holding or clicking a button.
• Visualize the shadow mode in an additional screen.

4. The Supervisor informs the Flight Centric ECs and PCs about

• the new sector configuration expected to be applied (if less controllers are required in conventional configuration, then some FCA positions will be closed),
• in case of SPO in FCA about the new controller teams in the new sector configuration,
• the new related frequencies,
• the traffic expected to be transferred to other positions.

5. Before the activation of the new airspace configuration (time horizons depend on local conditions), the FCA controllers, which will be the same when the conventional mode will be opened, can analyse the traffic situation in their CWPs (shadow mode), in two different options:

• Visualize the shadow mode in the same screen when holding or clicking a button.
• Visualize the shadow mode in an additional screen when the Supervisor has communicated the switch.

and if they have any doubt about the traffic situation of other flights not assumed by them, but which will be under their responsibility after the switch, they can contact via hotline the corresponding controllers to clarify the problem and keep situational awareness. If new controllers are needed, they will be able to maintain the situational awareness and ask questions from their CWP in shadow mode (since they are not controlling).

6. The Supervisor activates the new airspace configuration with conventional sectors and the Allocation support function is disconnected. In case the Allocator is not performed by the Supervisor he stops to work.
7. As soon as possible, the impacted Flight Centric EC and PC controllers transfer the identified flights to the conventional positions (if required), and the remaining flights stay with the same controllers (now as conventional controllers).
8. All involved controllers confirm to the Supervisor that all expected traffic have been received.

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 actions to be taken in Wide Area Communication over VHF to establish air-ground communication.

Preconditions

The Flight Centric EC needs to contact the Flight Crew.

Postconditions: Success end state

Communication with the Flight Crew is established.

Postconditions: Failed end state

Communication with the Flight Crew is not established.

Trigger

The Flight Centric EC needs to contact the Flight Crew, for example to answer the initial call or a request of the Flight Crew or to issue a clearance or instruction.

Main Flow

1. The Flight Centric EC identifies the flight he wants to talk to.
2. He clicks on the label of the respective flight (to activate the corresponding transmitter/frequency). Note: After clicking on the label the systems may need up to one second until the Flight Centric EC is able to send a radio message using push-to-talk (PTT).
3. He pushes the push-to-talk (PTT) button of the headset to initiate the voice communication with the pilot.

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

1. 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.
2. 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.
3. The Flight Centric EC activates the upload of the predefined CPDLC message.
4. The Flight Crew acknowledges the ATC instruction to monitor the next FCA frequency via CPDLC.

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 actions to be taken in a Flight Centric Area in case of an emergency descent.

Preconditions

Several aircraft are assigned to different Flight Centric ECs and are assumed.

Postconditions: Success end state

The aircraft has safely left the Flight Centric Area.

Trigger

An aircraft starts to descend, and the Flight Crew notifies the Flight Centric ATCO about the emergency descent and sets the squawk to 7700.

Main Flow

1. An aircraft starts to descend, and the Flight Crew notifies the Flight Centric ATCO about the emergency descent and sets the squawk to 7700.
2. The Flight Centric EC sets a flag in the particular aircraft’s label that this aircraft is doing an emergency descent (that means the emergency descent status is shared and notified to all other Flight Centric ECs) and the ATM system automatically sets this aircraft on “emergency” status in the CD&R tools.
3. This Flight Centric EC as well as the Flight Centric ECs controlling other aircraft take immediately all possible action to safeguard all aircraft concerned.
4. This Flight Centric EC as well as the Flight Centric ECs controlling other aircraft forward further clearances to all aircraft involved as to additional procedures to be followed during and subsequent to the emergency descent.
5. All Flight Centric controllers monitor the situation. Once the emergency descend has been completed the Flight Centric EC reroutes the dispersed aircraft to re-join the flight plan.
6. The ATS unit additionally informs any other ATS units and control sectors which may be affected by the emergency descent.

Note: In today’s operation the pilot stays on the frequency and the ATCO is responsible to coordinate the descent.

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 actions to be taken in a Flight Centric Area in case of fallback from main (primary) system to fallback system.

Preconditions

Failure of important segments of the main system.

Postconditions: Success end state

The Fallback System is working properly, Flight Centric ATCOs continue their work.

Trigger

Failure of two important modules of the main system. The main system may no longer be used for operations.

Main Flow

1. The CMMC displays failure of two important modules of the main system. A Technical Systems Operator detects this warning and informs the Supervisor.
2. All Flight Centric ATCOs are informed by the Supervisor and the Supervisor informs the Local Traffic Manager, the Flight Centric PC with EAP role and the EoD and they analyse quickly the situation (situation assessment).
3. All the surrounding sectors/units are informed (for example by the Flight Centric ATCOs) about the failure (according to their training concerning such situations) and the possibility of the switch to the fallback system.
4. The result of the situation assessment is that the main system cannot be used any longer and a switch to the fallback system must be done.
5. The Local Traffic Manager arranges the agreed Traffic Flow Measures.
6. All Flight Centric ATCOs are informed about the upcoming switch to the fallback system.
7. All surrounding sectors/units are informed (for example by the Supervisor) about the upcoming switch to the fallback system.
8. The fallback system gets started and runs properly.

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 actions to be taken in Wide Area Communication over VHF in FCA to establish air-ground communication in case of fall back from integrated to stand-alone mode (radar and communication systems are disconnected).

Preconditions

The Flight Centric EC needs to contact the Flight Crew and the connection between radar HMI and communication system is not working.

Postconditions: Success end state

Communication with the Flight Crew is established.

Trigger

The Flight Centric EC needs to contact the Flight Crew, for example to answer the initial call or a request of the Flight Crew or to issue a clearance or instruction.

Main Flow

1. The Flight Centric EC identifies the flight he wants to talk to.
2. He clicks on the respective callsign on the Voice Communication System panel (to activate the corresponding transmitter/frequency). Note: After clicking on the VCS panel the systems may need up to one second until the Flight Centric EC is able to send a radio message using push-to-talk (PTT). 
3. He pushes the push-to-talk (PTT) button of the headset to initiate the voice communication with the pilot