A-CDM: Partnership progress at Oslo Airport

Posted: 17 June 2014 | Gro Jære, Senior Project Manager A-CDM at Oslo Airport | No comments yet

In January 2014, Oslo became the ninth CDM airport in Europe. Gro Jære, Senior Project Manager A-CDM at Oslo Airport, details the successful implementation.

On 29 January 2014, Oslo Airport Collaborative Decision Making (A-CDM) connected to the Network Management Operations Centre (NMOC) in Brussels, becoming the ninth CDM airport in Europe and the first CDM Airport within Avinor’s network of airports in Norway.

To all stakeholders’ satisfaction, the goal was reached on time, within budget, and meeting all users’ quality requirements. The main benefits experienced so far are better planning capabilities for all the partners through common situational awareness and more accurate data. This is essential for achieving the cultural shift that A-CDM represents: from acting reactively to proactive planning. Passengers benefit from more accurate information, fewer gate changes and reduced risk of delays.

The Oslo A-CDM project was established at Oslo Airport in 2011 in close cooperation with EUROCONTROL and in partnership with Air Traffic Control (ATC), the main airlines (Scandinavian Airlines and Norwegian Air Shuttle) and the airport’s ground handling companies. Oslo Airport took ownership of the project, was responsible for project management and footed the investment in the common solution. The partners were obliged to assign a dedicated project member and to foot any investments in their own system. Furthermore, the Steering Group had members from all partners. All regulated through a Memorandum of Understanding.

In 2011, a pre-study was carried out based on a CDM Gap Analysis from 2007. A decision was made to implement the CDM platform in-house and develop a portal that would fulfil the users’ requirements. The solution is based on a Service Oriented Architecture in line with the development strategy for IT in SESAR. In 2012, the main focuses in the project were to describe the concept; develop the specifications and training material; develop the CDM platform; stakeholder management and to prepare for operational testing. The operational implementation of Oslo A-CDM took place in 2013 with the connection to NMOC as the final milestone.

Partners experienced several benefits after just a couple of weeks of being a CDM airport. For example, better estimates of in block times thanks to more accurate Estimated Landing Times (ELDT) and Variable Taxi Times (VTT), improved stand planning and a reduction in the number of late stand and gate changes. Consequently, passengers benefit from more correct information and fewer gate changes, lowering the stress that they experience while also reducing ATC work. Furthermore, ground handling can make better use of their resources and airlines are able to better plan their flights.

The introduction of Target Off Block Time (TOBT) in addition to ELDT and VTT improves the accuracy of Target Take Off Time. In addition to the benefits for the network, this improves the information from the handling company to the airline and arrival destination in situations where there are delays due to for instance de-icing.

Because the Calculated Take Off Time process is improved, the slots received are based on more precise information and ATC work is reduced.

Several of the initial airports that were CDM-approved have experienced delays during implementation. It was important for the project to learn from these to reduce the risk of delays. We have also benefited from the experience NMOC gained during the initial implementations.

One important learning point is to ensure that all the main stakeholders support the concept and decisions, and understand the consequences of them. Initially, the project focused on short-term benefits and we involved the users throughout the project.

Once the system design was under way, it became clear that seamless integration of existing systems at the ATC and ground handlers’ operations centres would be essential. For ATC this meant developing the tower system Electronic Flight Strip including the interface with CDM, so that it will support the necessary functions for CDM, for example de-icing and activating push and hold for regulated flights.

Supervisors use the portal to change the airport’s departure capacity and increase taxi times under special circumstances in addition to providing a good overview of the situation. ATC had a resource in the project’s core team, which was a key success factor in developing a practical solution.

“With increasing traffic and very complex winter operations, a good planning tool is essential to the controller. A-CDM has been a good experience for us, as it gives us reliable times for planning the sequence. We are looking forward to improving A-CDM further to fit our needs regarding winter operations in the years to come,” explained OSL TWR Supervisor, Frode Engen.

For the airline operator and the ground handler that verifies and updates TOBT on behalf of the airline, a mechanism for allowing airline operators to set their TOBT through an interface was required. Oslo evaluated the possibility of proposing a simple proprietary protocol, and started at the same time to investigate whether any available standards could be used in order to gain quick acceptance from the airline.

When we got information on the Airport Council International’s Airport Community Recommended Information Services (ACI ACRIS) initiative, which included a protocol standard proposal allowing flight publishing and TOBT updates, Oslo attended the early sessions of the standards committee. The available proposal already covered most of what Oslo would need, and the fact that the protocol was en route to becoming an ACI standard prompted us to vote for using the ACRIS CDM API in our design.

Once proposed to the airlines, the system was welcomed under the assumption that its implementation had the potential for re-use at future CDM airports. Implementation of the SetTOBT method followed the protocol without exceptions, and was successfully put into production in January 2013 during an early trial period as the first airport to adopt the ACI standard.

By spring 2014, we expect approximately 80 per cent of flights to have a TOBT update using the ACI ACRIS integration. Furthermore, there is a proposal to use the same mechanism for the next Norwegian airports to become CDM airports (Bergen, Trondheim and Stavanger). SAS CDM Program Manager, Allan F. Sørensen, cited the benefits of the ACRIS standard: “SetTOBT is issued when the handler updates the delay message (MVT DEL) in our existing Operations Control System. There is consequently no need to update both our current systems and CDM when we have delays, i.e. we reduce the amount of manual work and are certain to have the same estimated departure times in both systems.

“As an airline, the biggest challenge in our Flight Operations Control and Flight Dispatch Centre is that there is no single system available that can display A-CDM times for all A-CDM airports we fly to, but we depend on access to various A-CDM portals (Common Situational Awareness tools), which is not practical. The standard means that we can now integrate it into our internal systems and require our suppliers to comply with the standard.”

The implementation strategy, including user involvement, ensured hand-in-hand technical development and cultural change. The users were involved in the development of the CDM portal, and the solution was put into operational trial at an early stage. The users’ experiences were thus taken into account during the development, and the quality of the solution was well proved in parallel with the implementation of CDM procedures. The technical team has delivered quality throughout the project, and this has built the necessary confidence in the system. The operational implementation of OSL A-CDM took place in 2013 and was carried out according to the CDM manual, and further divided into three steps:

  1. TOBT processes – the ground handling companies started to update TOBT on behalf of the airlines according to CDM procedures. As soon as the data quality was proven, TOBT was prioritised above EOBT in the Electronic Flight Strip in ATC
  2. CDM start-up procedure ‘best planned, best served’, local implementation of CDM procedures
  3. Connection to NMOC – testing and implementation.

Each operational step was prepared in writing with operational plans including purpose, goal, start-up criteria, roles and responsibilities.

One important decision regarding implementation was the start-up procedure. The subject of major discussion in EUROCONTROL’s Harmonisation Task Force, many good arguments were brought to the table both to support the view that pilots should report ready at Target Start-up Approval Time (TSAT) and at TOBT. At Oslo we chose TOBT, mainly because of the airlines, and due to the fact that TOBT is the airlines’ responsibility while TSAT is ATC’s responsibility. TOBT and TSAT represent the handover from airline to ATC. We believe this has made implementation easier, since this represents a smaller change for the pilots compared to the TSAT procedure.

Another important aspect of the implementation strategy was to make the CDM concept work locally at Oslo. A lot of time has been invested in understanding the CDM concept, and discussing local procedures and benefits. The implementation manual is an excellent guide, but it must be understood locally, and at the same time it is important to harmonise throughout Europe. In the initial part of the project we prioritised a local focus, based on the hypothesis that if it works locally, it will work for the network. Even though, we started to work out the Interface Control Document towards EUROCONTROL at an early stage. The work and help from EUROCONTROL and their ability to respond quickly and thoroughly on questions have been an important contribution to the project’s success.

Besides the project partners, there are a lot of other important stakeholders that need to know about CDM including catering, cleaning and fuelling companies, as well as other airlines flying to Oslo. We conducted more than 50 information meetings throughout the project and developed information material aimed at different user groups.

Ensuring the success of the project required its prioritisation by all partners, i.e., allocating resources with the right skills and attitude with firm organisational backing. The management’s declaration that success was expected also helped keep the project on track.

In the future we look forward to further improvements and benefits as Avinor implements CDM at Stavanger, Bergen and Værnes, and the enlargement of the network in Europe. At Oslo, our partners are working to further improve CDM and situational awareness will be further improved when CDM information is available at docking and on mobile devices.

Furthermore, we will improve the sequencing tool to better support winter operations. In the end, the most important issue is to remain focused on operational procedures, to make sure TOBT is updated in due time and the pilot reports ready according to the rules.

What is A-CDM?

In its implementation manual, EUROCONTROL defines A-CDM as:

“The concept which aims at improving Air Traffic Flow and Capacity Management (ATFCM) at airports by reducing delays, improving the predictability of events and optimising the utilisation of resources.

Implementation of Airport CDM allows each Airport CDM Partner to optimise their decisions in collaboration with other Airport CDM Partners, knowing their preferences and constraints and the actual and predicted situation. The decision making by the Airport CDM Partners is facilitated by the sharing of accurate and timely information and by adapted procedures, mechanisms and tools.

The Airport CDM concept is divided in the following elements:

  • Information Sharing
  • Milestone Approach
  • Variable Taxi Time
  • Pre-departure Sequencing
  • Adverse Conditions
  • Collaborative Management of Flight Updates.”

For further information about A-CDM visit:


Gro Jære began working at Oslo Airport May 2012 and has since become Project Manager for the A-CDM project. Gro has a MSc in Engineering Cybernetics, and has also joined a Master of Management Program including Project Management. She has more than 15 years’ experience from different industries.

Send this to a friend