Article

Time to rethink infrastructure ownership

17 June 2022

This covers

Innovation, research and simulation

Network operations

Aviation sustainability

Disruption and crisis management

Paul Ravenhill of Think Research, one of the authors of the European Airspace Architecture Study (EAAS), discusses why in addressing volatility we need to rethink infrastructure ownership as part of the transition to the Digital European Sky.

The global pandemic and war in Ukraine have cast air traffic management’s (ATM) issues into stronger contrast: the traditional approaches we have to design and operate ATM infrastructure are not resilient to large volatility in demand.

ICAO’s Chicago Convention placed responsibility for ensuring ATM service provision on States. At the time, this naturally meant that States provided ATM services themselves, designing infrastructure around local requirements in terms of expected traffic. To provide additional capacity, the air navigation service provider (ANSP) could really only add a new sector. As the complexity of traffic (and ATM) grew, sector design became a real art. Just look at the sectorisation between the UK and France – see how well aligned it is with normal traffic flows in and out of London and Paris airports. It has a beauty of its own, but these very specialised sectors come at a price – the diminishing returns of further sectorisation.

Adding a new sector in any airspace is a complex undertaking that can take several years from identifying the need to the final validation and operation. When traffic demand is growing at a steady two to four per cent per annum, as historically it appears to have done, then airspace designers can plan ahead and meet demand.

The simple truth is that growth in demand isn’t really linear. Various crises over the years have led to sharp and dramatic falls in traffic, followed by accelerated growth. The current global pandemic is by far the most dramatic, and hopefully one-off, event. ANSPs had to reduce capacity significantly, and already we are being warned that Summer 2022 is going to be a difficult time because replacing capacity is just as hard as stripping it out.

Sadly, geo-political events like the war in Ukraine are not a one-off. The closeness of Ukraine to the EU and NATO States makes it seem rare, but armed conflict anywhere in the world can move a major air route in Europe from one State to another. We shouldn’t think that volatility is only caused by disasters; on a more temporary basis it can be generated by events such as the Olympics or football World Cup, with a major impact on flows. As can a change in preferred holiday destinations.

The truth is the closer you look the more volatile traffic appears. Global and European traffic forecasts may look like steady growth, but traffic flows themselves might be much more chaotic – even at sector level we can see volatility caused by convective weather. Have a look at Canada’s airspace design for receiving the North Atlantic flows which moves on a daily basis.

Volatility is caused by the airline business models being faster to react to external stimuli than the traditional ANSP business model. It has always been such. An airline can drop an unprofitable route overnight and develop a hopefully profitable one in a matter of weeks. In that timeframe all an ANSP can do is adjust the air traffic controller (ATCO) roster – paying more or less overtime. If the swing becomes large and sustained then the ANSP begins retraining ATCOs, adding sectors, adopting new technology all of which takes years and comes with the risk that demand has changed again before they are implemented.

The solution is to adapt the ANSP business model to react as fast as the airlines. In Europe that means sharing the problem across all the ANSPs. Initially through the EUROCONTROL’s CFMU (Central Flow Management Unit) and then Network Manager, Europe’s ability to understand demand and apply Demand Capacity Balancing has improved substantially since the 1990s and put the days when holiday makers feared spending as much time at the airport as they did on the beach behind us; but modern technology can take us further.

"Volatility is caused by the airline business models being faster to react to external stimuli than the traditional ANSP business model"

The novel solution in the EAAS is “Capacity on Demand” – a surprisingly simple idea where an ANSP with spare capacity opens a sector on behalf of an ANSP with insufficient capacity, with a lot of implementation complexity: who pays? How is the data distributed? How is the opportunity identified?

The SESAR3 Joint Undertaking is coming up with the answers through virtual centre projects, but there is a wider airspace design issue that needs to be addressed at network level. For future concepts like Capacity on Demand, we want more harmonised sectors. Rather than use sector splitting we need to use controller tools and automation to increase capacity. Fundamentally, if any controller could control any bit of airspace we need to harmonise separation standards and sector design so that controllers validate on the system and not the airspace.

Traditionally the Area Control Centre (ACC) is the beating heart of the national system. Communications, navigation and surveillance (CNS) is planned around the Flight Information Region and monitored from the ACC equipment room. This has also moved on.

ANSPs no longer own large parts of the CNS infrastructure they rely on. Outsourcing of ground-ground communications started at least 20 years ago, culminating in Europe with PENS (pan-European Network Service). GNSS (global navigation satellite system) is aviation’s use of navigation aids initially developed for the military (GPS) and citizens (Galileo). The SATCOM system used for FANS (Future Air Navigation Systems) in oceanic airspace is owned and operated by Inmarsat, and through the Iris project the modern equivalent will be available in continental Europe. The Aireon spacebased ADS-B system is providing an additional surveillance source.

In order to provide an air traffic service for a given volume of airspace, the ANSP is responsible for ensuring adequate CNS infrastructure for the desired separation standard. Documents like the ICAO Gold Standard defined the requirements for communications, navigation and surveillance. The modern ANSP is using a mix of their own assets and services from the likes of SITA, Inmarsat, ESSP and Aireon to demonstrate the safety (and interoperability compliance) of the ATS service.

As we move the more dynamic distribution of sectors to ACCs, this responsibility needs to become a collective responsibility of all the ANSPs. The EAAS separates the provision of CNS and ATM data services from ATS provision with the suggestion that different business models might emerge in the different layers, but rightly is silent on what they might be – after all the market decides.

ATM is of course a unique industry, with market pressures applied by proxy through Economic Regulation in Europe (and often just pressure from the customer elsewhere). ATM is a public service whose provision States have agreed to ensure. While making some parts of the ATM market contestable may drive economic benefit for the airlines, the lesson to be learned from the recent upheavals is more about how risk is shared and priced into the services.

The main risks are traffic and system development/ deployment costs. Using dynamic airspace sharing as part of the Demand Capacity Balancing solution set allows traffic risk to be shared. Think about the Network Manager collaboratively agreeing the sector opening plan to even out traffic across the ANSPs, leading to more stable ATCO requirements and reducing local risks.

Sharing system costs is different. Risk can be taken by both the supplier and the purchaser. The reason ANSPs are able to rely on external systems like GPS, Galileo, Aireon and Iris is that the development and deployment costs were borne by external providers. To some extent aviation gets a free ride.

ANSPs have traditionally taken the full risk of developing the ground ATM system. As the requirements become more and more complex, ANSPs have looked to common procurement to share that risk (COOPANS and iTech being great examples). However, with the emerging ATM Data Service Provider (ADSP) models, it is the ADSP that takes the risk – and if the ADSP includes the supplier then we are sharing the risk with the organisation that is best able to control it.

We know we need ATS. We know airspace is sovereign. We know the military have an important role to play both as airspace user and service provider. We know the costs of transitioning to a new system will be high.

Given all that we need to talk more about how risk is shared. By using the AAS’s “five layer” model we can have a more nuanced debate about risk. We can foresee sharing risk with specialist organisations that operate similar systems within aviation or beyond. We can look at national ANSPs becoming ATSPs providing flexible and scalable ATS based on consuming ATM data and CNS services rather than taking the entire risk of ownership.

"Rather than use sector splitting we need to use controller tools and automation to increase capacity"

In Europe the SESAR programme and the Network Manager give us the ability to develop and adopt technical solutions that better manage volatility, but if we are to do so costeffectively we need to address business models and asset ownership fully. Now is the time to agree on what the ANSP of the future looks like.