Article

Modernising airspace for a new era of aviation

7 March 2023

This covers

Digitalisation and information management

Juliet Kennedy, Operations Director at NATS, outlines how increasing resilience is an integral part of the UK's airspace modernisation programme from the UK air navigation service provider.

Over a century ago, when the feet of early aviation pioneers finally – fleetingly – left the ground, little did they realise that they had defined the future of world travel, trade and tourism.

Wind the clock forward 100 years and much that defines modern life depends on aviation. Now we face another paradigm shift as a new generation of airspace users, with uncrewed and remotely piloted vehicles, electrification, and extremely high-altitude platforms among others, mark the next chapter in our aeronautical journey.

Given the advances of the last century in airframes and propulsion, airspace is one notable element of our industry that has been much slower to embrace radical change. Of course, it has undergone incremental adaptations to meet growing demand; but the hallmarks of its original design back in the 1950s are still very much in evidence. And what provided resilience in the past will not provide us with the resilience we need for the future.

Today in UK airspace we safely and efficiently handle more than two million flights every year – more than those pioneers could ever have imagined (and with one of the lowest delay rates in Europe). NATS is very future-focused because we have to be. We handle a quarter of Europe's traffic despite having only 11% of its airspace; we are a major transatlantic gateway with one of the world’s premier hub airports at Heathrow, scheduled to 98% of its capacity, and we operate one of the most complex networks in the world in the London TMA with five major airports within a tight geographic radius. Resilience is key to what we do, and we know only too well what happens when we don't have enough.

Aviation has always been an interesting bellwether of the global economy, inherently cyclical with peaks and troughs throughout the year becoming more pronounced as economies grow or recede – aviation is used to dealing with uncertainty. COVID-19 took this to a new extreme as the world closed down. Traffic dropped to less than 10% of normal levels in 2020 and recovered in 2022 to more than 80% of 2019 levels. The story of what happened during those two years has tested the resilience of our industry to the maximum as markets around the world have opened and closed at different times and in different places, in response to unfolding events. And of course, even though commercial traffic may have stopped, airspace remained open and fully resourced to support cargo, PPE and emergency flights.

Coupled with the situation in Ukraine, which has put additional strain on adjacent airspace, this has translated into probably the biggest challenge ever to the industry's resilience and its ability to adapt and flex as circumstances have changed.

We have seen shifting traffic flows across Europe and in the UK, with pinch points emerging in both the airspace and the schedule as normal traffic patterns and busy periods have flexed to deal with constraints. There has never been a more critical time to address the network challenge by cracking on with airspace modernisation and accelerating it wherever we can, to build in resilience for the future. By 2050, when the industry has committed to delivering net zero, the new era of airspace users will be operating, and we'll be providing a service that meets their needs. Put simply, modernising airspace is essential.

"There has never been a more critical time to address the network challenge by cracking on with airspace modernisation and accelerating it wherever we can, to build in resilience for the future"

UK airspace is considered critical national infrastructure and is one of the most complex networks in the world. As the volume and types of aircraft that use it continue to grow, achieving greater efficiency requires new airspace concepts and technologies that can simplify the way it works. Direct trajectories from take-off to boundary, continuous climb and descent, less (and higher) airborne holding, and Free Route Airspace (FRA) are concepts already in place, many of them developed with European colleagues in SESAR (Single European Sky ATM Research) research programmes and which are crucial to enhancing efficiency, reducing emissions and minimising delay not just within our own airspace, but in service of developing the ultimate goal of a single European sky.

The UK's Airspace Modernisation Strategy (AMS), co-sponsored by the Government (the policy maker) and the Civil Aviation Authority (CAA, the regulator) is currently being updated to reflect the latest developments and factor in new users.

Like all Air Navigation Service Providers (ANSPs), NATS has a duty to accommodate safely and efficiently any user that has a legitimate demand on our airspace, whether that is a commercial passenger aircraft, a private recreational aircraft, an eVTOL taxi or a high-altitude, long-range drone that delivers 5G services from 60,000ft. The challenge is doing so without airspace access becoming a blocker or negatively impacting decarbonisation efforts.

While this is still a major work in progress, we know that integrating new types of aircraft, rather than segregating them into their own pockets of airspace, will be crucial if the airspace is to remain accessible to all users and enable all types of aircraft to fly where they want, when they want, and on demand. Achieving that level of integration will require ANSPs such as NATS to modernise the service we provide and the way we manage the airspace.

"The breakthroughs in technology are changing both the way we use the skies and the types of aircraft that take to them"

NATS continued our network modernisation programme throughout the pandemic because it has never stopped being the airlines’ top priority. We all know that sustainable fuels are still a decade away at commercial scale, while airspace modernisation will deliver within the next decade significant carbon savings in support of the aviation industry's 2050 net-zero goal. Estimates vary up to 20% but we know that once they are in place, improvements generally deliver more fuel savings than the usually conservative expectations built into project plans.

In December 2021, we delivered the biggest airspace change we have ever done, introducing Free Route Airspace over Scotland, the North Sea, the North Atlantic, Northern Ireland and some of northern England. It has enabled a reduction of 12,000 tonnes of CO₂ per year – equivalent to the carbon emissions of 3,500 family homes. Up to 2,000 flights using this airspace every day now fly the route they want between a defined entry and exit point, rather than having to fly along demarcated corridors between navigation beacons.

Over the past two years, our Operational Service Enhancement Programme (OSEP) has deployed six small tranches of change to airspace across the UK, delivering some big benefits. In all, they are saving some 30,000 tonnes of CO₂ annually throughout the European and UK network, equivalent to the emissions from the energy usage of over 8,000 homes. OD6, the most recent in December 2022, was a change to Humber Sector, currently the second most regulated high-level sector at Prestwick. With a new flexible boundary allowing us to split the sector dynamically, we expect to reduce delay and emissions, and improve routings through both Scottish and London Upper Information Regions (UIR). The change adds extra route connections between Prestwick, Copenhagen, Maastricht and London Area Control and links Scottish and Maastricht FRA. There are new conflict areas, different traffic flows and new procedures with Copenhagen and Maastricht. OD6 alone is expected to deliver substantial fuel savings, enabling up to 18,000 tonnes of annual CO₂ reduction throughout the European network.

And this month we will introduce our most complex modernisation project so far, including the second deployment of FRA in the high-level network (above 24,500ft) over the west of England and Wales, together with a systemised lower network (above 7,000ft). This project will introduce large-scale systemisation for the first time in UK airspace, with a more efficient and direct route structure in this busy section of UK airspace expected to enable savings of over 12,000 tonnes of CO₂ per year.

But airspace modernisation isn’t just about the structures. Hand in hand with new design concepts is technology transformation and tools and our 10-year, £ 1 billion technology roadmap which underpins our airspace modernisation programme.

The Deployment Point (DP) En Route and Voice programme is key to this transformation, consolidating multiple aging systems into a single platform for upper airspace. The new adaptable technology platform will enable the full benefits of redesigning airspace, such as cross-border Free Route Airspace, and support innovation into the future. Our Second Voice System (SVS), a backup communications system in the event of a main voice system failure, is set to be in full operation later this year and provides enhanced resilience and capability.

Other tools are already proving their value. One example is the Extended Arrival Management (XMAN) tool in operation at Heathrow and Gatwick. Working cross-border with neighbouring ANSPs, XMAN helps avoid conventional holding by slowing aircraft and absorbing any forecast delay into the more fuel-efficient cruise phase of flight. At Heathrow alone this saves around 8,000 tonnes of fuel each year.

Another is Intelligent Approach, an arrival spacing tool that means we can improve the consistency of spacing between aircraft based on their wake vortex, optimising runway efficiency and delivering better on-time performance. We developed this with Leidos and with airport customers, and first introduced the time-based separation module of the tool at Heathrow in 2015, which has reduced headwind delays by about 60%, making the operation more resilient.

So, the breakthroughs in technology are changing both the way we use the skies and the types of aircraft that take to them. Before 2030 we can expect the return of supersonic flight (only this time without the carbon cost), electric air taxis moving people between and within urban centres, and remotely piloted drones delivering goods, connecting communities, and performing complex tasks.

A greater level of digitalisation and automation of the services we provide today both inside and outside controlled airspace will be one of the fundamental building blocks required for this new way of managing airspace, as will the need for every aircraft to see and be seen by other airspace users using tools like electronic conspicuity and detect and avoid systems. Research is gathering pace into how data science and artificial intelligence can be used in air traffic management to support next-generation ATC systems and use automation to reduce controller workload.

As the aviation ecosystem evolves and expands, the role of an airspace manager will also remain critical in areas of busy airspace to ensure all aircraft are safely separated, and able to enjoy the benefits of an integrated and modernised airspace. As the UK's leading provider of air traffic control services, and with decades of experience in this industry, we are confident we can do that.

This is the beginning of a new era for aviation across the world, and certainly in the UK. Working with partners across government and industry, our airspace modernisation programme is driving forward new tools, technology and airspace design to deliver a sustainable and modern network; one that continues to make air travel in the UK as safe, quick and resilient as possible, and fit for whatever the future might bring.