It is universally accepted that the way airspace is used will change dramatically over the next decade. New users will include small unmanned air systems (sUAS, or drones), large airships or the long-endurance, solar-powered and unmanned craft that may replace expensive communications satellites, and even commercial space passenger flights. The advances in technology that have made these once exotic-sounding applications a reality have occurred have occurred across numerous areas including artificial intelligence, automation, sensors, batteries and solar cells.

A combination of this technical progress with increased commercial demand for the services they could provide mean an exponential increase in airspace use is inevitable. However, these new aircraft will need to operate safely not only with each other but also with existing air traffic, as demand for traditional passenger and freight transportation shows no sign of abating.

Industry response

The rising number of airspace users coupled with a significant shift in the mix of aircraft will place a new set of demands on the communication, navigation and surveillance infrastructure. This has already been recognised by all the leading industry bodies. ICAO’s Aviation System Block Upgrades programme, as outlined in 2016’s ‘Framework for Global Harmonisation’, includes a thread on digital air traffic management (ATM) information management that is aimed at addressing the need for increased data integration, and supporting a new concept of online information exchange.

SESAR’s latest version of the European ATM Master Plan includes for the first time explicit reference to remotely piloted aircraft systems (RPAS), and states that the ATC network will "evolve with digitalisation technology" to support more diverse users.

The FAA and SESAR have active research in the area of UAV traffic management (UTM), with the aim of integrating non-traditional airspace users into the existing ATM picture safely and efficiently.

With specific reference to the communications infrastructure that will be needed, SESAR’s ATM Master Plan communications roadmap identifies the major trends in the evolution of aeronautical communications. They can be summarised as:

nncontinued use of ground-air voice, namely very high frequency (VHF) radio, supporting critical communications, as well as the provision of ultra-high frequency (UHF) radio for state aircraft

nnmigration towards ground communication networks based on distributed internet protocol (IP) technology to enable network-centric architectures

nna greater deployment of voice over internet protocol (VoIP) supporting ground communications; digital voice for air-ground communications may be introduced in the longer term

nnwidespread implementation of air-ground datalink communications that will supplement air-ground voice.

nnthe introduction of new technology and the use of distributed IP networking technologies for the ground and the airborne sides will require the provision of greater security capabilities addressing (cyber) security concerns and relevant threats.

The first point here is critical, but could almost be overlooked in the enthusiasm to embrace new technology; the backbone of ATC communications is – and will remain – VHF and UHF voice. Pilots and crew will remain on board the vast majority of passenger aircraft for many years to come, and voice over VHF radio is likely to remain the primary form of communication with controllers. As such, the foundational capabilities provided by traditional radios will be required in the ATC network of the future.

The opportunity for those involved in the design and development of ATC ground-to-air radio communications equipment is to evolve the trusted and reliable, but often decades-old, ground radio into the hub of a digitally enabled, highly flexible and scalable communications network that supports voice and data.

Designed for digital

Northrop Grumman’s UK-based ATC Communications subsidiary, Park Air, have been in the business of ATC radios for over 50 years. Park Air radios are in operation in almost every country in the world, and the company has been among the leaders in implementing new advances such as VHF datalink in 1997 and VoIP in 2010.

Many of these developments were incremental changes to established products. With the Sapphire Communications range launched in 2015, Park Air is now delivering complete ATC communications systems, and at the heart of Sapphire sits the Park Air T6 radio – the first radio designed specifically with the digital ATC network of the future in mind.

With Park Air’s heritage in this field, it is only to be expected that the T6 offers class-leading RF performance, giving excellent range and sensitivity, even in highly congested radio environments. What really sets it apart, however, are those features that enable it to sit comfortably within an increasingly digital and data-enabled communications system.

It is fully compliant with all the latest VoIP protocols (ED137 A/B/C, G711/G729 and IPv4/IPv6), can support as many as ten simultaneous VoIP sessions and up to four IP voice recorders. It has dual redundant IP ports with configurable services on each. While maintaining full backwards-compatibility, it has unrivalled connectivity, scalability and security for future voice and data communication.

For users and maintainers, these networking features bring a host of benefits. The radios support redundant system architecture, giving high resilience and minimum risk of critical failure. They are interoperable with the widest range of voice control system (VCS).

Critically, the T6 is able to support not just a growth in the local communications network size but also increasing diversity and complexity of airspace users, with differing voice and data communications requirements.

Security in mind

With an increasingly digital and interconnected communications network may come an increase in concern over data assurance and system security. The Sapphire system and Park Air T6 radio are able to support the individual security requirements of different users managing networks of differing complexity.

The T6 supports industry standard HTTPS and SNMPv3, including encryption and authentication, and the innate flexibility of the radio means it can be configured to match a user’s individual network security philosophy.

It also has the ability to receive remote software upgrades, including security updates and patches that can protect against new threats. As with any IT network, new threats will continually emerge seeking to exploit any perceived network weakness, and ensuring protection is regularly updated will be critical.

The changing nature of airspace use is set to bring huge societal advantages, and the recognition of these benefits has prompted the sometimes-conservative ATC industry to embrace the change. In his 2017 speech to the Global Operations Conference in Madrid, CANSO director general Jeff Poole spoke of the benefits to future ATM networks of increased automation, and the need to welcome unmanned aircraft into the system.

This will only become a reality if the supporting infrastructure is designed for the traffic of today and of the future. Park Air’s Sapphire and T6 radio show how the traditional foundation of voice communication can evolve to meet the needs of the digital ATC network.