Why the remotest idea is a good one…

With Africa predicted to be one of the fastest-growing aviation regions over the next 20 years, the pressure on its aviation infrastructure is set to grow. Jon Lake reports.

Appropriate, affordable and cost-effective infrastructure development will be critical to the sustainability of any future expansion of African aviation.
A key part of that infrastructure lies in the provision of adequate air traffic control (ATC) services, which may be required at airports that may be used on an irregular basis, or that are geographically remote.
Some airports may log very small numbers of arrivals and departures each day and manning the tower permanently at such airfields can be problematic, and wasteful, if not prohibitively expensive. But these airports can be immensely valuable to the local communities, providing a lifeline with the outside world, and closing them may not be desirable.
One solution, now being marketed by Saab Digital Air Traffic Solutions, is to use what the Swedish company calls a ‘digital aerodrome’ concept, leveraging its newly developed remote tower system.
This system, developed under a joint venture with Sweden’s air navigation service provider Luftfartsverket (LFV), promises to revolutionise air traffic control by allowing a number of airports to be controlled from one location, allowing small and medium sized regional airports to remain competitive and reduce costs.
The system uses a range of remote sensors, including video, audio and others, to provide a continual, comprehensive view of an airport. It also incorporates sophisticated software and datalinks to allow ATC services to be provided by personnel located at a remote tower centre (RTC) located many miles away from the airfield.
Personnel in the RTC look at a high-definition real-time synthetic picture from the remote tower that is almost indistinguishable from what would be seen from a conventional tower in the same location, though symbology can also be overlaid on the picture of the outside world, as it might be in an aircraft head-up display, further enhancing a controller’s situational awareness.
Airspace users are provided with exactly the same appropriate level of service from the remote tower as if it was being provided locally at the airport from a conventional tower.
Tracking is visual, and is overlaid with radar information, while pixel detection allows even the smallest objects to be spotted, tracked and identified. The technology can penetrate fog, mist and rain, and can detect wild animals on runways. Even birds and very small drones (with a wingspan of 18 inches or less) can be detected from ranges of 2,500 metres.
In Sweden, sensor turrets can use compressed air to clear snow away from the camera lens!
The same pictures can easily be streamed to the airport fire service, or to local handling agents, further improving airport efficiencies.
Using the remote tower system, a single air traffic controller could manage more than one airport from an RTC. Work on developing, validating and analysing how this ‘one man multi-airport’ operation could be achieved has been undertaken as part of the European Union single European sky air traffic management research (SESAR) development programme.
The remote tower system can also be used to augment the capabilities of manned towers, allowing emergency/contingency services to be provided at major airports, if a fire or other emergency (or even routine maintenance) prevented use of the usual control tower building.
The contingency remote tower facility would be at a different physical location, and so would be able to continue unaffected, maintaining high traffic throughput and capacity.
The same sensor systems can also be used to increase situational awareness in a conventional local airport tower by providing for the synthetic augmentation of vision in poor visibility.
A remote tower system could be deployable, with sensors mounted on something like Saab’s Giraffe radar system, which is air-portable on board a C-130 Hercules. This would allow an austere forward air base to be provided with enhanced ATC services during deployed military operations, for example, or during humanitarian relief missions.
The remote tower passed site acceptance testing (SAT) in February 2013, paving the way for full operational certification by the Swedish Transportation Authority later that year.
The system was declared operational in Sweden in April 2015 after trials, in which Saab sensors were deployed at Ornskoldsvik Airport, provided data to a RTC at Sundsvall, 100km away. This feat earned Saab the prestigious IHS Jane’s ATC award for delivering the first operational and approved remote tower in the world. It was presented on March 7 2016 at the World ATM Congress in Madrid, Spain.
Subsequently, further RTCs were installed at Sundsvall and will be installed at Linkoping City Airport this year.
Further trials were undertaken in the USA (at Leesburg Executive Airport, Virginia) Norway, Ireland (with a remote tower at Cork, and another at Shannon, both controlled from Dublin) and at Alice Springs in Australia, the latter using an RTC 1,500km away in Adelaide.
More recently, live traffic at Groningen Airport Eelde has been controlled from the remote tower working position at Schiphol, Amsterdam.
Saab said it has another three potential customers (one of them a military user) “lined up”.
In Africa, one limiting factor to growth and expansion is likely to be the number of trained and qualified ATC controllers. The International Civil Aviation Organization (ICAO) has forecast a global requirement for 40,000 air traffic controllers by 2030, as the world’s airlines double their combined fleet of commercial jets and as the number of passengers approaches 7 billion per annum.
Remote towers promise to allow a more efficient use of ATC manpower, helping to ease the flow of traffic around major airports as they expand, and allowing the operation of airports that might otherwise be too expensive to keep open.
They look likely to allow Africa to make the most efficient possible use of its manpower resources.