IFPLID uniquely identifies a flight plan. When a flight plan is cancelled in the ATM world it doesn't necessary mean that the flight leg is cancelled. Often a flight plan will be refiled and a new IFPLID created. After the flight leg is airborne the IFPLID will stay the same for the rest of the flight leg. NB! When an ATM cancellation is received IFPLID should be cleared to avoid any matching issues.
See AircraftData for details. All aircraft related data, much of which is also reference data. Reference data is copied to this entity to ensure that the exact aircraft configuration for the flight leg is preserved.
