1 Manchester Airport’s Electronic Flight Progress Strip systems were upgraded with Departure Plan-ning Information software earlier this year. Other UK regional airports are following suit. Manchester Airport 2 Time Based Separation was introduced at London Heathrow in March. NATS estimates the technology could save 80,000 minutes of delays per year at the hub. Airops1/AirTeamImages

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controllers’ screens with what NATS calls “dynamic wind indicators”, but there is no modification to arrivals procedures. Flights continue to be radar-vectored on to final approach with the same speeds.

Real Time InformationNATS isn’t the only organisation to introduce new ATM technology in the UK. Transport Systems Catapult, the UK Government-backed transport innovation centre, is

leading a project called Departure Planning Information (DPI) working alongside NATS, airports and the regulator.

Using software developed by Nav Canada, DPI provides real time information about a flight’s status on the ground just prior to departure. It enables air traffic controllers in the airport towers to send departure information messages with accurate take-off time predictions to the European Network Manager.

The system issues real-time progress updates from when an aircraft is cleared for pushback to when it’s taxiing and when it has taken off. Crucially, the information is then sent to the air traffic network managers, giving them a more accurate picture of departure times.

The Transport Systems Catapult acted as a broker to secure funding from the Department for Transport to introduce the software at a number of UK airports.

ccording to Civil Aviation Authority figures, 2.1 million flights travel through UK controlled airspace annually. That number is predicted to grow to three million per year by 2030, which

means there’s greater attention on how to move flights through the country’s air traffic network efficiently.

As the UK’s aviation regulator, the Civil Aviation Authority (CAA) is at the heart of this process with its Future Airspace Strategy (FAS) to introduce more direct routings, optimise runway operations and use advanced air traffic management (ATM) technology.

The CAA believes this will yield fuel, emissions and time savings for airlines and release more airspace for other users. The FAS is being developed and deployed in line with the European Commission’s Single European Sky project, which seeks to simplify and harmonise air traffic control throughout Europe.

Work currently under way to achieve the goals of the FAS was highlighted during the Imagine Festival in Milton Keynes in June. During a presentation Phil Roberts, the CAA’s Head of Airspace, Air Traffic Management and Aerodromes, said: “What we’ve tried to do with FAS is get the airports, airlines and air traffic services providers to align their individual investment plans, so the air traffic control system has got the ability to use new technology to the best effect.”

Arrivals ManagementNATS, the UK’s air navigation services provider (ANSP), is naturally playing a significant role in this process (see Clever Control, November 2014 p64-69). Its initiatives include iFACTS, a software tool that enables air traffic controllers to calculate flight path trajectories more accurately, continuous descent operations for more efficient routings, and the Cross Border Arrival Management System (XMAN) for London Heathrow

XMAN uses open data exchange technology to improve information transfer between NATS and adjacent European ANSPs. Sharing data regarding delays in the holding stacks at Heathrow means flights approaching UK airspace can absorb any delays while still cruising, with the result that they hold in the stack for less time and save fuel and emissions.

Time Based SeparationNATS’ latest technology initiative is Time Based Separation (TBS), introduced at Heathrow in March. Airports usually use fixed-distance separations for arrivals. But when headwinds increase, an aircraft’s ground speed reduces, which lowers the landing rate and lengthens holding times – a major issue at Heathrow, which runs at 98% capacity.

TBS, developed by NATS in conjunction with Lockheed Martin, uses real-time data downlinked from the radar aboard arriving aircraft to calculate the wind speed on final

approach. This data provides updates to controllers and generates a time separation equivalent to the distance separation in a 5-7kts (9-12km/h) headwind.

Fundamental to the system’s development was a five-year study at Heathrow that used LIDAR (light detection and ranging) remote sensing equipment into how wake vortices on final approach disperse. The research showed a vortex decays faster if headwinds increase, and enabled Lockheed Martin and

NATS to develop new rules for separation minima that account for both headwinds and an aircraft’s wake vortex category.

Time Based Separation reduces the separation between arrivals if the headwind strengthens and increases it when there is a tailwind or little wind. Separations are therefore managed ‘dynamically’; either increased or reduced as conditions dictate, to best optimise arrivals.

The separations are visualised on

TECHNOLOGY UK AIR TRAFFIC CONTROL UK AIR TRAFFIC CONTROL TECHNOLOGY

New technologies to boost air traffic efficiency are being introduced in the UK, as Mark Broadbent reports

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The first phase involved working with NATS to upgrade the existing Electronic Flight Progress Strip (EFPS) systems in operation at Aberdeen, Edinburgh, Glasgow, London City, Luton, Manchester, and Stansted.

DPI became fully operational at Aberdeen, London City and Manchester earlier this year, and was scheduled to go live at the other four airports in July. In March, the Catapult awarded a contract to Lockheed Martin for a second phase to develop and deploy DPI at regional airports operating traditional paper flight strips.

Efficiency GainsThe Catapult and NATS say efficiency savings from the new technologies are already evident. Analysis of offline trial data has shown a 60% improvement in the accuracy of predicted take-off times due to the DPI project, according to the Catapult.

Speaking at the Imagine Festival, the Catapult’s Chief Operating Officer, Mark Ruddy, said: “Without DPI messages, the levels of air traffic control do not have a fully accurate picture of departure times. If an aircraft is late in departing, air traffic network managers would not necessarily know this until the aircraft is airborne.”

The consequence, NATS told AIR International is that: “Network demand/capacity balancing has greater uncertainty around it and cannot be managed as efficiently as it can be with the DPI messages.”

The Catapult estimates DPI will reduce start-up delays (classified as those before aircraft leaves the stand) by 3%. NATS said DPI will also bring greater benefits to arrivals management tools such as Heathrow’s XMAN, which has reduced stack holding times by two minutes. The company reckons that combined, DPI and XMAN could save airlines £10 million over five years.

NATS said the Time Based Separation project at Heathrow has had an immediate impact. The company revealed that on March 30, with a 35kts (64km/h) headwind on final approach, its controllers landed on average two more aircraft per hour than in similar conditions on March 2, before TBS was introduced. NATS added that Time Based

Separation “is on track to save 80,000 minutes of delays per year at Heathrow”.

Next StepsThe introduction of new technologies will continue. The next major step in implementing the FAS nationally (for which the timescale extends to 2030) is the phased introduction, over the next four years, of the NATS London Airspace Management Programme.

This will introduce performance-based navigation, which uses the Precision RNAV (radio and satellite navigation) functionality embedded in airliners’ flight management systems to enable crews to fly routes with accuracy to within a mile or better. Where the traffic can support it, Required Navigation Performance (RNP) parameters

may be applied.NATS intends to introduce arrival manager

tools and continuous descents and climbs at other airports around the UK, while the CAA has FAS development groups for northern and Scottish airports to apply lessons from the Southeast to improve efficiency nationally.

Data ExchangeThe issue uniting all these efforts is data exchange. Roberts said: “We [need to] share information in the most efficient way so we can try to ensure this whole, rather complex, jigsaw [the airspace system] comes together. That relies on IT systems and the ability to handle large amounts of data.”

He added that the wider Single European Sky ATM Research project to improve data exchange between ANSPs across Europe is influencing the definition of protocols that systems will use to share information.

Better JourneysIn their presentations at the Imagine Festival, Ruddy and Roberts both stressed that IT systems need to be designed in such a way that information directly applicable to passengers (for example, the length of security queues and gate details) is part of the data exchange, and is communicated to flyers.

They added there is also a need to ensure information regarding delays in other transport modes (such as road and rail) that passengers use to travel to airports, is also integrated into the system.

The long-term goal is to achieve a smooth flow of information between airports, airlines and NATS within the UK, between those organisations and other transport sectors, and between the UK and its European neighbours.

“If we can share information sensibly, the whole network can run better,” Roberts concluded.

TECHNOLOGY UK AIR TRAFFIC CONTROL

1 Departure Planning Information software issues real-time progress updates from when an aircraft is cleared for pushback, to when it’s taxiing and when it has taken off.

Jorge Guardia Aguila/AirTeamImages 2 The busy airspace in the southeast of the UK, with London Heathrow running at 98% capacity, brings a sharp focus on new

technologies that improve efficiency. Simon Gregory/AirTeamImages

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