Surface CDM

Airport Collaborative Decision Making in Europe

A Guide to Why Sharing Airport Data Makes Sense

Splendid Isolation

Imagine yourself sitting at the gate, waiting to embark your flight. You’re early, and you see the aircraft arriving at the stand. It barely came to halt when different rolling stock and teams aim for  the aircraft doors, almost in perfect unison.  Almost, because those different vehicles and teams often belong to different aircraft handling companies  and most of the time, airport players operate in ‘perfect isolation’, not necessarily taking the needs or restraints of the other into consideration.

Let’s zoom out a bit: turnaround activities of your flight have finished, but caught a delay earlier on due to a baggage conveyor of ground handler A with a flat tire, which blocked the catering truck of ground handler B. The departure time is restricted by Eurocontrol’s Network Manager due to air traffic congestion, but the aircraft won’t make the allocated ‘slot’.  The airline was advised of this delay by handler A, but cannot make a correct estimation of the problem and counts on local Air Traffic Control instances to still be able to clear the aircraft for pushback. Only, the tower controller doesn't know of any delay from handler A or B, and has no means to advise the Network Manager (formerly known as CFMU) that your aircraft will not be airborne as planned…

Enjoy this vintage strip from the World famous Belgian comic strip book series “Suske en Wiske” (translated in English nowadays as “Spike & Suzy); standard airport operations caught in one image…

“No member of a crew is praised for the rugged individuality of its rowing”  R.W. Emerson

Apart from frustrated handling teams, a stressed out airline which is faced with an unforeseen delay which it could not anticipate, and you, nail biting in your seat and wondering why it’s always taking so long at this bloody airport, your aircraft blocks air space capacity at the time it was expected to be airborne, and puts a strain on air traffic flow and capacity management.

By the turn of the century, air traffic growth predictions skyrocketed, and both air traffic service providers and airports saw themselves faced with future capacity issues. Add to this the fact that in the early 1990s, about one fifth of all airborne take-off slots in Europe went to waste, partly as a result of -involuntary- cases of ‘rugged individuality’ by airport stakeholders. Jokingly, air traffic control considered  airports to be black holes, in which aircraft disappeared after landing, without ever knowing when they would emerge again.

Time to start acting…

Square One

Already in the late 1990s, European decision makers started looking at an American decision making initiative called CDM, later renamed as Surface CDM, which was first rolled out at San Francisco International Airport in 1998.

The concept was mainly focused on en route capacity restrictions and bad weather situations, less on turn-around operations. Nevertheless, the concept of making collaborative decisions to enhance operational predictability was withheld in the ATM Strategy 2000+, in which future European air transport needs were outlined. It was then further elaborated by Eurocontrol and developed into what we now call A-CDM, or Airport Collaborative Decision Making.

'The Network Dimension'

We’ve come a long way, and meanwhile, A-CDM characteristics were written down in Community Specifications by European standardization bureau ETSI, as mandated by the European Commission. The content is based on 3 EUROCAE (European Organisation for Civil Aviation Equipment) documents, which list the minimum technical  specifications, interface specifications and validation guidelines to make your airport A-CDM. In turn, this documentation, together with a detailed description of the operational concept, refers to the content of the A-CDM Functional Requirements Document  and, last but not least, the Implementation Manual; the ‘Holy Bible’ which you’ll find on the bedside table of all of us into A-CDM  (well, most of us…).

Requirements, guidelines, specifications, manuals… this must be Europe! And indeed, the ‘network dimension’ makes us different from other airport collaboration initiatives across the globe. Not only do we exchange data between the local stakeholders  at our airports -which is already challenging; we are also invited to share our decisions with the Network Manager, and this can easily be called both ambitious as well as underestimated.

How does one become European-style A-CDM?

It takes quite a bit for that… Next time, I’ll guide you through the 6 steps of the operational concept, from getting the Memorandum of Understanding signed by all your data sharing partners, up to linking your airport to the Air Traffic Flow Management Network.

This article is part 1 in a series of 6 articles on European Airport Collaborative Decision Making

Additional Resources Eurocontrol Airport CDM