Precision satellite approach technology for airports21 December 2017
Pilots have recently landed aircraft in the Faroe Islands and at Bremen Airport in Germany using new precision satellite approach technology. Stephen Hall speaks to Jákup Sverri Kass, CEO of Vágar airport, Jóhanna á Bergi, CEO of the Faroe Islands official airline, and Christian Knuschke, head of aviation at Bremen, to discuss a system that could make air traffic controllers obsolete.
The Faroe Islands were formed by volcanic activity 30 million years ago. First populated by Irish monks in the sixth century, these mysterious isles still have a population of fewer than 50,000, but the appetite for tourism to this archipelago in the north Atlantic is burgeoning. Vágar is one of the largest of 18 islands on the Faroes; it’s also the site for the only airport on the island, accommodating almost 300,000 passengers a year. Since 2012, these flights are facilitated by signals from the skies that accurately guide passengers to its great lakes and picturesque landscapes with incredible accuracy.
Atlantic Airlines is the national carrier of the Faroe Islands; established in 1987 and running its first flight a year later, it’s owned by the government, but is operated on a totally commercial basis. It was the Faroes’ only air service for more than 20 years, until Scandinavian Airlines provided some competition. Its three aircaft serve 12 countries, but this underdog of the air uses the most advanced airspace technology in Europe. RNP AR 0.1 increases its satellite signal approach to within 3m and enables aircraft to follow precise three-dimensional curved flight paths.
It uses the European Geostationary Navigation Overlay Service (EGNOS); the first pan-European satellite system was instigated in 2011 and improves on the open public service offered by the US’s global positioning system (GPS). The RNP method doesn’t require air traffic controllers and saves the airline the equivalent of €160,000 a year in fuel costs.
In combination with this new approach, Vágar Airport has extended its runway from 1,250 to 1,799m. The longer airstrip has increased regularity and now accommodates incoming flights from as far afield as the Canary Islands.
A new approach
Inside Vágar, Jákup Sverri Kass, the jovial CEO in charge of Vágar Airport, has a lot less work on his hands thanks to the new system. The Faroese advise anyone who doesn’t like the weather to wait for five minutes, for it is the islands’ changeable conditions – prone to fog and turbulence – combined with its mountainous topography that created headaches for Vágar officials.
“The approach to Vágar Airport is over high ground in both runway directions, and the approaches from the north-west require pilots to fly a non-linear approach path,” Kass explains.
The RNP method has made things much more straightforward, improving efficiency and reducing environmental impact. “This approach has saved us a lot of time and it translates to a fuel economy saving of about 250kg a journey,” Kass enthuses.
Service reliability has improved as well. In the second half of 2012, after implementation, 20 diversions were avoided and in July 2071, 18 approaches were successful that would not have been possible with the manual method. The outlay for the new system was around €2.8 million, but “has already paid off, due to the decrease of diversions”, Kass reveals.
Atlantic Airlines instigated the system and received authorisation from the DCAA in March 2012 for an evaluation period of six months, with final approval obtained in November 2012. Jóhanna á Bergi has been CEO of the company since 2015.
Previously, cancellations or alterations due to unfavourable weather would cause knock-on disruptions for days at a time, as the nearest alternatives to Vágar Airport are in Iceland, Scotland or Norway. This would cost Atlantic thousands in compensation costs.
“Sometimes people would have to stay overnight,” Bergi laments. “Atlantic would have to put people up in hotels, but now there are almost no diversions when there is a heavy wind.”
Another significant benefit has been the ability to fire around obstacles using satellite, as well as the capability to make curved approaches to land, navigating turbulent conditions.
“The RNP is 0.1, which is the only one we know of in Europe, if you look at the approach minimum that we had before, and now,” Bergi declares proudly. “You have a much lower minimum as well, which means you go an hour to ten minutes for each approach.”
As well as significant time savings, Atlantic has reduced labout due to fewer diversions, but the system has also seriously affected what was previously the most important job within the airport.
“This is 100% satellite navigation, so there’s nothing for the airport to do,” Bergi clarifies. “There are air traffic controllers in the towers the whole day; we tell them which approach we are flying and that’s it. They have to be there for an emergency and so on, even with RNP.”
The Faroe Islands isn’t the only location where traffic controllers have been left to twiddle their thumbs. In 2012, Germany’s Bremen Airport, which serves approximately 2.7 million passengers a year, was the site of the world’s first ground-based augmented satellite approach.
Five years later, the hub used the EGNOS system for Germany’s first passenger aircraft landing completed without the aid of any conventional ground-based navigation infrastructure; using a new satellite-based precision approach procedure.
In April, two pilots from Netjets, the largest business jet company in Europe, were involved in the trial, as well as officials from Bremen Airport flying a business aircraft. The flight was a success, gliding through clouds to land safely, guided precisely to a height of 200ft by means of satellites, horizontally and vertically. Once the runway was within the pilot’s sights, he was able to safely land.
But what makes this humble, mid-sized hub in the north-west of Germany so willing to innovate in this area? Christian Knuschke is head of aviation at Bremen Airport and he’s well aware of the pioneering spirit of his workplace.
“For certain reasons, we have a huge complex of the German air navigation services located here at the airport; it’s a good place where you have all the technology around,” Knuschke discloses. “Also, the aviation industry and the aerospace industry are very strong in Bremen. We make these projects hand in hand.”
As well as its prime location, Bremen doesn’t need any new infrastructure investments to implement this method. EGNOS consists of 40 reference stations in more than 20 countries Europe-wide, picking up signals from GPS satellites.
“The satellite system is already in place,” Knuschke clarifies. “Right now, we have five satellites. The EGNOS network gives us the infrastructure all over Europe to establish these navigational procedures.”
The satellite-based augmented system is a step up from its ground-based alternative, which requires a land station within an area of 23nm around the airfield. “If the signal becomes closer to the airport, the accuracy becomes better,” explains Knuschke, “and therefore we also have the chance with the GBAS to establish, in the future, CAT 2 and 3 approaches, but with SBAS we are able to establish CAT 1 approaches without the cost of having ground stations at the airport.”
Netjets and Atlantic have innovated with their satelliteonly landings, but now the ground has been broken – with fuel savings of up to 4%, cost savings for airlines and a host of other benefits – what barriers are standing in the way of widespread adoption?
“Most modern aircraft are equipped with avionics systems that are approved, all these aircraft can use the SBAS system if the company has certain procedures in place but the flight operation department of certain airlines need to have training as well as procedures for the SBAS approach,” Knuschke explains.
“It’s no longer a technological issue, because the avionic is in place at most aviation companies.”
Satellite approaches like the ones used in the Faroe Islands and Bremen enable an increase in air traffic because more planes can take off and land every hour. With passenger numbers snowballing every year, the pressure on air traffic controllers and overburdened airlines is only set to increase. The satellite-based approach using the RNP 0.1 could go some way to alleviating that pressure.