About the exercise

The exercise validated iinitial 4 dimensional (i4D) trajectory through the issuing of Controlled Time of Arrival (CTA) to inbound aircraft. CTA is calculated thanks to ground-ground datalink coordination between air traffic control sectors and air-ground datalink coordination between aircraft and ATC.

CTA allows pre-sequencing of inbound traffic, which supports safe, smoother and more cost effective operations.

Results

Validation activities in Rome showed that:

• CTA allocation does not impact safety;
• The concept allows improvements of vertical efficiency: flights were flown at higher, more fuel efficient altitudes and descended following a fuel efficient Continuous Descent Profile.

The concept leads, however, to a deterioration of horizontal performance, which needs to be further investigated.