Validation projects

Controlled Time of Arrival (CTA) in medium density and complexity environments

Release: 2015

Reference: -

Location: Toulouse


The Controlled Time of Arrival (CTA) is an imposed time constraint at a defined point associated with an arrival runway, using airborne capabilities to improve arrival management. When a time constraint is needed for a flight, the ground system can calculate a CTA as part of the arrival management process, proposing it then to a flight which uses its on-board avionics to achieve the required accuracy. Airborne information may be used by the ground system in determining the CTA (e.g. ETA min/ max) and in monitoring the implementation of the CTA.

Description of the exercises

A series of exercises in Malmö and Toulouse will assess the maturity of the CTA solution and the impact on performance when applying CTA in the Extended Terminal Manoeuvring Area/En-route environments. The exercises will also assess the operational acceptance of CTA by controllers and flight crew.

A combination of flight trials and real-time simulations taking place in Rome and Toulouse respectively will aim to demonstrate compatibility between Airborne Spacing - Interval Management, Sequencing and Merging (ASPA-IM-S&M) and initial four dimension trajectory (i4D)/CTA operations. The exercises will also validate that ASPA-IM-S&M can realistically be integrated into an Extended Arrival Manager (E-AMAN) horizon and brings added value compared to conventional procedures. An important aspect of these exercises will be to assess the acceptability of ground-ground interoperability with regards ASAS and i4D/CTA, in terms of information exchange and coordination, as well as the impact on pilots’ organisation.

Expected benefits

  • Enhanced predictability
  • Improved fuel efficiency
  • Increased capacity in TMA / En-Route phases
  • Cost effectiveness
  • Enhanced safety