Advanced ATC TWR airports

An Advanced ATC TWR airport provides only a subset of DPI messages from their TWR systems to NMOC.

What is it ?

The best way for an airport to integrate into the ATM Network is to implement the Airport Collaborative Decision Making (A-CDM) process as specified in the Airport CDM Implementation Manual.

However, airports that have no plans to implement the A-CDM process but still wish to integrate into the ATM network may do so as an Advanced ATC TWR Airport. Such an Airport may provide a reduced set of DPI messages with a reduced set of advantages (compared to CDM Airports).

An Advanced ATC TWR Airport provides Target Take-Off-Time (TTOT) estimations as well as Variable Taxi-Times (VTTs) and SIDs to the NMOC. These are provided from the moment that the aircraft leaves the blocks.

How does it work in a nutshell?

The exchange of dynamic information between the NMOC and the TWR at the airport is a two-way process which consists in:

  • sending DPI messages from the TWR concerned to the NMOC. These messages contain the latest information on, for example, estimated times for the take-off of a particular flight, the aircraft type, taxi times, and the SID;
  • sending Flight Update Messages (FUM) from the NMOC to the airports concerned, providing the Airport CDM platform with the flight status, the estimated landing times, etc.

The main information to be received via the DPI message is:

  • an accurate estimate of the take-off time;
  • the taxi time;
  • the departure route (SID)

This allows the proactive sharing of real time data with the NMOC, therefore optimising the ATFCM slot allocation process and achieving a more efficient use of the ATFCM network capacity.

Pre-requisites for becoming an Advanced ATC TWR Airport

In order to qualify for integration into the ATM network as an Advanced ATC TWR Airport the following must be available:

  • Variable Taxi-Time
  • Actual Off-Block event
  • Return-to-Stand event
  • Communication set-up TWR-NMOC
  • Connection to the AFTN network

For more details please refer to the Advanced ATC TWR implementation guide.

If possible the Advanced AT TWR Airport could also provide the following information for the benefit of the ATM network and its users:

  • the confirmed/verified Aircraft type and registration
  • the Actual Off-Block Time (AOBT) and Date (AOBD)
  • the information that the flight will be or has been de-iced

How can the Network Manager assist airports?

EUROCONTROL and the NMOC strongly support the development, harmonisation and dissemination of new methods and best practices to meet the requirements and expectations of airports.

As a first step, the NMOC can provide initial information on the DPI and FUM messages to airports - after the Advanced ATC project implementation decision has been taken.


The overall objective of the FUM/DPI message exchange is to better coordinate ATFCM with ATC at the Airport in order to ensure the punctual updating of flight data, more consistent slot calculation and improved slot adherence. 

Departure Planning Information (DPI)

This airport situational information is collected direct from the TWR system at the Airport in order to update the real-time flight situation, prior to take-off, in the Network Operations systems.

Thanks to this improved accuracy of flight information, DPI ultimately serves to improve ATFCM traffic predictions andn consequently, the effectiveness of the ATFM measures to be taken.

For Advanced ATC TWR Airports one phase has been identified which requires coordination with ATFCM:

  • ATC phase or pre-sequencing: At delivery of engine start-up clearance delivery, the flight is handed over to the tower for push-back, taxiing and take-off. Local control units (ATC/Apron) will ensure that the flight goes off-blocks and takes-off as close as possible to the local target times (TSAT, TTOT).

Flight Update Messages

The objective of the FUM message is to provide the airport with an accurate estimated landing time of arriving flights in order to improve the planning of outbound traffic.

Benefits of becoming an Advanced ATC TWR

The benefits for an airport to become an Advanced ATC TWR Airport are:

  • the CTOT is frozen at the moment the aircraft leaves the blocks
  • IFPS no longer accepts flight plan updates (DLA, CHG) messages after the flight has left the blocks
  • The TWR may benefit from extended Slot Tolerance Windows (STW) for flight that require de-icing.
  • Flight Activation Monitoring (FAM) is based upon the Take-Off-Time received from the airport, which reduces the risk on FLS messages due to “not reported as airborne” in case the flight suffers from a longer ATC Ground delay.

The benefits for the ATM network are:

  • improved Traffic predictability for FMPs in en-route ACCs,
  • improved flight plan consistency
  • improved situational awareness for AOs when the aircraft is at an outstation via CHMI, NOP portal and NMOC’s data distribution service
  • improved estimated landing time estimates for Airports of Destination (ADES) via the NMOC’s data distribution service for airports (FUM message)

Implementation support

The NMOC is ready to assist any airport that would like to explore the possibilities of integrating into the ATM Network as an Advanced ATC TWR Airport.

The assistance consists of:

  • explanation of the concept
  • exploration of the possibilities of becoming  an Advanced ATC TWR Airport
  • discussing and agreeing the DPI message interface in detail
  • agree the implementation planning
  • organise & support the integration test phase
  • put into operations

For more information, please do not hesitate to one of the persons listed in the Contacts tab.

The Implementation phases are described in detail in the DPI and FUM Implementation Roadmap document.

Implementation Status

The following table sets out the European Airport DPI implementation plans that have been provided by Advanced ATC TWR airports to the Network Manager Operations Centre (NMOC).

Advanced ATC Tower Implementation Status map