Link It

Link It

With Link It project ENAV tests and implements the data link services for airspace communications (CPDLC – Controller Pilot Data Link Communications) that replace certain voice exchange instructions between the controller and the pilot with pre-formatted messages.

During the controller's normal work, actually, instructions such as a change of flight level or a change of frequency relating to the sector are spoken directly to the pilot, using radio channels.

Using the data link services the controller sends the airspace communications, by completing pre-formatted messages which are transmitted with the support of new functionalities, integrated into the human machine interface (HMI) of the console.

The introduction of CPDLC mainly increases operation safety, by guaranteeing no misunderstandings take place, which is typical of voice communications, as well as guaranteeing the integrity of messages exchanged between the controller and the pilot.

Other advantages are: a reduction in congestion of the airspace band frequencies, a reduction in the pilot’s and controller’s workload and, as a result, an increase in airspace capacity.

ICAO has defined multiple CPDLC services that support normal ATC functionalities. These services are not time critical and therefore will be used where operating conditions allow, without impacting on operation safety.
Initial CPDLC services are:

• DLIC (Data Link Initiation Capability)
• AMC (ATC Microphone Check)
• ACL (ATC Clearance)
• ACM (ATC Communication Management)

ENAV has always been involved in the implementation of CPDLC, since it is considered the key to entering the future of ATM.
In 2001 ENAV decided to support the Eurocontrol “Link2000+” program whose objective was the operational implementation of the initial CPDLC services, by conducting various research to define the basic project requisites, for example, the identification of airspace where data link services could be used and the strategic choices for technical and operational implementation.  

The initial business case enabled the analysis of the feasibility of data link service use, the operational environment, the impact on safety and the analysis of the choice of technology to use. 

The approval of this business case gave way to the formal start of the first "Link It" project phase, a test and validation phase of the operational methods introduced by the data link applications.

Using two series of Real Time Simulations it was possible to validate new, CPDLC services work methods, using an application prototype of the data link functionalities implemented in the HMI in operation in Roma ACC. 

A Fast Time Simulation verified an increase in the sector capacity, but above all the simulations enabled verification of the safety assessment results conducted with an analysis of the behaviours and limit cases that impact on operation safety by demonstrating the safety introduced by CPDLC. 

At present the "Link It" project, which has passed the testing phase, has reached the operational implementation of initial CPDLC services in the UIR managed by Rome ACC as early as 2010. Besides, the project foresees the implementation of the services DCL (Departure Clearance) and D-ATIS (Digital – Air Traffic Information Service) at the airports of Fiumicino and Malpensa. Subsequently, they will be implemented in the UIR in Padova and Brindisi, in compliance with European Community legislation, which introduces the obligation to use CPDLC services from 2013 ("Implementing Rule" by Single European Sky).