POI-0013-IS — Improving the Tactical Trajectory by using ADS-C Data

The Tactical TP underpins the Tactical decision tools which are a key enabler to realising the benefits of Trajectory Based Operations (TBO).
The tactical tools exist to support medium term decision making and are built upon a high resolution trajectory prediction algorithm with a relatively short prediction horizon of up to 30 minutes.
Whilst an aircraft¿s performance envelope may be well understood, the actual performance of a specific flight is dependent on a number of operational factors, including payload and fuel carried, and operator preferences (e.g. selected cost index).
In the absence of flight-specific operational data, a ground trajectory predictor has to make assumptions about aircraft behaviour.
Consequently it is necessary to apply a large uncertainty around that assumed trajectory to encompass all possible flight profiles for that aircraft type or sub-type.
Past SESAR activities have shown that an unknown aeroplane mass and speed schedule are the major contribution to Tactical Trajectory Predictor (TP) uncertainty.
This OI step is related to the use of the ADS-C data (mainly mass and speed) received from the airplane in climb or descent phases to replace assumed performance data in the Tactical TP, thus improving the performance of the predicted trajectory.