Fuser Flight Plan Handling

Summary

Flights will sometimes file multiple flight plans to ERAM before departure time. For example, we might see a CLT departure flight with more than one flight plan in ZTL ERAM, with the same route, but different PTimes (departure times). Why does this happen? It could be by mistake, or it could be intentional. For example, if a GA pilot isn't quite sure when they will depart, they might file an extra flight plan for a later time to keep one alive in ERAM, just in case the earlier flight plan might time out in the system.

When this happens, ERAM will generate a new computer ID (CID) for each flight plan. In general, the Tower controllers will sort out any duplicate flight plans and cancel the unnecessary ones before the flight enters the movement area.

The Fuser matches multiple flight plans to the same flight, but only stores a single "current" set of flight plan data (e.g. PTime, route, source facility, computer ID, etc) in the Fuser database. With the AEFS integration, it is becoming increasingly important to introduce flight plan management for pre-departure flights. AEFS communications require knowing the current computer ID in the messaging. Previously, the Fuser data would merely update with the data from the most recent message.

Pre-Departure Flight Plan Management

The Fuser manages a list of FlightPlan elements for pre-departure flights for each Fuser Flight Object element. Each FlightPlan in the list corresponds to a unique source facility (e.g. KZTL) and computer ID (e.g. 455). The authoritative source for FlightPlan data is currently TFMS_Flight messages that are triggered by ERAM. Eventually, we may switch to SFDPS. This authoritative source is the only source that can update the FlightPlan elements in the preDepatureFlightPlanList.

The FlightPlan data elements are data that can appear in an ERAM flight plan message, and use the same names as the "current" elements in the Fuser Flight Object:

• timestampSource
• lastUpdateSource
• systemId
• sourceFacility  
• computerId     
• eramGufi                 
• flightPlanCanceled             
• aircraftRegistration            
• beaconCode              
• flightRules
• flightType
• aircraftType
• aircraftEngineClass
• aircraftEquipmentQualifier
• wakeTurbulenceCategory
• departureStandProposedTime
• departureAerodrome
• arrivalAerodrome
• routeText     
• standardInstrumentDeparture
• standardInstrumentArrival  
• departureFixSourceData
• arrivalFixSourceData   
• altitudeAssigned
• altitudeRequested
• altitudeFiled
• speedFiled

The flightPlanCanceled element is set to TRUE when the Fuser receives either of:

• TFMS cancellation message triggered by a HCS_CANCELLATION_MSG
• AEFS remove strip message.

Flight Plan Data Handling

The Fuser detects when the "current" flight plan data in Fuser database is out of sync with the incoming messages. Generally, updating with the latest incoming messages works fine, but there are cases when it doesn't. In these cases, the Fuser will inject a new message into the Fuser processing queue with lastUpdateSource = "FUSER". There are two types of FUSER messages:

• Flight Plan Cancelation : If the "current" MatmFlight flight plan computer ID is canceled, the Fuser sends a message, systemId=FUSER_FLIGHT_PLAN_CANCEL. This message includes the elements of the most-recently updated, not canceled, FlightPlan.
• Flight Plan Correction : If the "current" MatmFlight flight plan computer ID is different than a new incoming message, the Fuser sends a message, systemId=FUSER_FLIGHT_PLAN_CHANGE. This message includes the elements of the corresponding FlightPlan that matches the incoming message.

Multiple Flight Plan Indicator

The Fuser mutlipleFlightPlansIndicator is TRUE when there is more than one "active" (i.e. flightPlanCanceled = FALSE) flight plan computer ID, from the same sourceFacility. As duplicate flight plans are canceled, the mutlipleFlightPlansIndicator will change to FALSE.

ERAM Identifier Mediation

ERAM is the ATC system that manages flight plans. The Fuser doesn't currently have a direct ERAM feed. The Fuser current authoritative source for flight plan data is the TFMS SWIM feed messages that are triggered by ERAM. These messages have the highest preference for setting computerId, sourceFacility, and eramGufi. And they are the only elements capable of affecting the FlightPlan data in the preDepartureFlightPlanList.

STBO Flight List

The STBO flight list now includes a CID column with the current Fuser database computer ID, and a "Mutliple CIDs" column that indicates when a pre-departure flight has multiple active flight plans in ERAM.