Alderney airport, in the Channel Islands, uses EGNOS to enhance operational safety and ensure continuity of robust vital links
Alderney is one of the eight inhabited Channel Islands, located in the English Channel near the French coast of Normandy. The Channel Islands are not part of the UK, but a dependency of the British Crown. Alderney, in the Bailiwick of Guernsey, has a surface of approximately 8 km2, with a population varying between 1,800 and 2,000 inhabitants.
Flying is the easiest and most convenient way for transporting people to and from the Island. Alderney airport – the smallest of the three Island airports and the closest to both French and UK mainland – is managed by the Guernsey Airport authorities on behalf of the States of Alderney. It has three runways, used by public and commercial flights. Within the Airport Authority, the Air Traffic Control Unit is responsible for providing the safe and efficient management of flight operations.
Aurigny Air Services, the local airline, operates regular, charter and private passenger and freight flights between the Channel Islands, Western France and England. Regular flights are vital for the small Alderney community, since the island depends on air transport for the routine supply of goods, including post and daily newspapers, and for evacuations in case of medical emergencies (medical facilities on the island are limited).
Weather conditions, together with the constraints created by the proximity of French airspace, can make it very difficult, even for experienced pilots, to approach the runways of the Alderney airport. In particular, bad weather conditions regularly force operators to delay, divert or cancel scheduled flights, with negative consequences for the airline and its passengers, and also for the local economy.
The satellite solution
In 2011, Aurigny Air Services started using a landing system based on EGNOS (the European Geostationary Navigation Overlay System), a system that improves navigation by reducing errors in GPS data.
The funding to implement the service was received by Aurigny and NATS (the UK air traffic control-provider for commercial flights), through the European Commission’s Trans European Networks (TENs) programme, which supports the global International Civil Aviation Organisation strategy to move away from ground-based and towards space-based landing systems.
The system was first tested on two of Aurigny’s Britten-Norman Trislanders and was then extended to the whole airline fleet. EGNOS uses three geostationary satellites and a network of ground stations to verify the accuracy of and correct the GPS positioning signals. The new system provides both lateral and vertical guidance to touchdown on the runway, with the pilot cross checking his altitude with the altimeter, allowing an approach to the runaway without local ground-based navigation support, enabling successful landings in low-visibility conditions which might have prevented landings in the past.
One of the advantages of the system is that it does not require the installation of additional equipment on the ground, thus limiting costs. Since the new procedures were designed to be integrated with those previously used by the pilots and the controllers, ATC staff needed only limited training to start using the EGNOS system. The only relevant costs for the Airport Authority are those related with the initial design and the maintenance of the approach procedures.
The system is currently installed on six aircraft, and has been used every day during the last two years.
EGNOS reduces errors in GPS data and provides pilots with both lateral and vertical guidance and better minima (i.e. decision height and runway visual range), allowing them to approach and land on the Alderney runaways in difficult weather conditions.
The use of the EGNOS system makes the Alderney airport far more accessible for commercial operations, ensuring safety and continuity of air services from and to the Island. It also enhances the competitiveness of the local airline, by minimising delays or costly diversions (which also have an impact on the amount of fuel burned), it increases comfort and safety for the passengers, and it better supports the local economy which relies on air transport.
By the first operational implementation of the EGNOS system for commercial flights, Alderney Airport proved the profitability and advantages of the service, while also leading the way for other small airfields in Europe.
“The EGNOS system ensures service continuity and operational safety, while also reducing workload for both airline flight crews and for the traffic controllers on the ground”, Frank McMeiken, Manager ATC, ATC Guernsey and Alderney Airports