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Managing the Skies

Few barometers provide as accurate an indication of a changing economy as the aviation industry.


July 28, 2009
By James Marasa

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Few barometers provide as accurate an indication of a changing economy as the aviation industry. Unfortunately, for operators weathering the economic climate of the past 12 months, the mercury has been steadily declining. As airlines worldwide restructure to traverse a challenging fiscal landscape, air navigation service (ANS) providers in the United States and Europe are undertaking a massive modernization of their air traffic management (ATM) systems. Canada, as well as nearly every other developed nation in the world, has aircraft flying through these airspaces every day. In a time when every dollar counts, Canadian operators need to understand these changes and how they will impact their bottom line.

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The modern era of air travel has brought with it an unfortunate expectation among passengers that their flight will likely be delayed. For the majority of these travellers, a delay is a mere inconvenience; however, the compounding effect of delays spurs consequences far beyond travel insurance claims. Aviation is not a niche industry. In a very broad sense, air transportation is a pervasive conduit through which international business is able to flow. While efficiency will forever remain a functional objective, it becomes critically important as carriers worldwide seek to recover losses and remain solvent.

Efficiency can be taken in broader context than a purely economic one. Though responsible for only two per cent of the world’s carbon expenditure, air transportation has a particularly sour reputation among environmental circles. Even with fuel efficiency having improved roughly 70 per cent in the last 40 years, the International Panel on Climate Change (IPCC) has estimated a 12 per cent inefficiency exists in ATM worldwide. In tangible terms, airliners flying racetrack patterns as they await further clearance pump roughly 80 million tonnes of carbon dioxide into the atmosphere each year.

Nevertheless, carbon credits do not pay the bills and economic pressure remains the most persuasive factor influencing change. Giovanni Bisignani, director general of the International Air Transportation Association (IATA) put it bluntly: “if there were ever an incentive to improve environmental performance, it is the industry’s US$186 billion fuel bill.”

Six years ago, US Congress released the “Century of Aviation Reauthorization Act,” calling for a revitalization of the FAA air traffic control system. The Next Generation Air Traffic System, known colloquially as “NextGen,” will incrementally replace the ground-based system of radar and VHF airways with satellite-based surveillance and GPS navigation over the next 15 years.

Automatic dependent surveillance broadcast (ADS-B) technology will eventually replace radar sites across North America giving controllers more accurate position information than ever before. Expected to be fully operational in the US by 2013, ADS-B will allow controllers to “see” aircraft where current gaps in radar coverage require the use of restrictive procedural separation standards. Additionally, pilots will benefit from improved situational awareness in the cockpit due to enhanced, on-board traffic and weather displays. It has been argued that enhanced surveillance and navigational technologies could reduce current radar separation standards, allowing controllers to space aircraft more closely together and facilitate more fuel-efficient direct routings. Some believe that the vision of NextGen could be expanded to the point where all aircraft, using enhanced traffic information in the cockpit, could self-separate, a concept known as “Free-Flight.”
 
In 1994, Michael Baiada, a captain at a major US airline, co-authored the first study that brought Free-Flight to the attention of the aviation community. The study prompted congressional hearings that directed the FAA to accelerate development of the Free-Flight concept. A critic of the legacy air traffic control system, Baiada has argued that pilots should be allowed greater autonomy in separation and navigation decisions. Proponents of Free-Flight favour broadening the scope of automated self-separation to foster a “collaborative decision-making process” between pilot and controller whereby finer adjustments are made farther out from the point of potential conflict.

The European Economic Community faces a similar issue of congestion but must tackle an additional complication. While Canada and United States have the luxury of employing sweeping technological enhancements across vast expanses of airspace, Europe must massage such large-scale changes across political boundaries. According to Harry Bush, director of Economic Regulation for the UK Civil Aviation Authority, setting up a system involving 27 service providers rather than just one presents a huge challenge. Bush has publicly advocated that now, while there is some “breathing space,” is the time to build a stronger platform for sustainable growth in air traffic for the future.

Europe is no stranger to stretched capacity.  From 2003-2008, air traffic in Europe has increased almost 20 per cent, driven primarily by the rise of low-cost carriers. Delays correspondingly increased roughly 34 per cent over the same time period with traffic expected to double by 2030. Single European Sky ATM Research, known as SESAR, is underway to harmonize air traffic management procedures across the European Union.
 
It may require a shift in perspective to see any benefit that a faltering economy could bring about to the future of aviation; however, as Bush has suggested, this is an exceptional opportunity for air navigation service providers to raise capacity for the inevitable resurgence of demand. According to Bisignani as he spoke to the ICAO NextGen/SESAR Coordination Meeting in Montreal last September, “this is a unique opportunity and we must get it right.”

With avionics upgrades required to operate under Next Gen and SESAR expected to cost as much as US$40 billion, users certainly have reason to hope the ANS providers get it right. Some operators have elected to wait for avionics requirements to stabilize before investing in new avionics, fearing costly upgrades may be required as the system is refined.

As capable as these new systems may be, anything suggesting a fast or easy change to the way air traffic management is conducted could quickly be dismissed as unrealistic idealism. Though technology may one day give pilots the ability to self-separate, there are several factors that must come into play. For a pilot to make safe and effective separation decisions collaboratively with a controller, it would require local knowledge of traffic flows, departure and arrival routings, conflict points and restricted airspace. It is difficult to envision a “collaborative decision making process” having any practical application in a complicated and busy airspace where separation decisions are made and implemented very quickly. Though it is tempting to blame delays on an antiquated radar/airway system, will reducing separation standards create a definable gain in efficiency?

According to Eurocontrol, of the 11 per cent of flights that experienced delays in 2007, 56 per cent were attributable to the airlines themselves, with nine per cent due to weather. Of the remaining delays, only 12 per cent occurred while aircraft were operating in the en route environment, most likely due to holds imposed because of a congested airport or terminal. At any rate, that means 1.32 per cent of flights in Europe in 2007 experienced a non-weather-related delay en route with all other delays occurring from causes not attributable to en route ATC efficiency.

The advantages of ADS-B in what is currently non-radar airspace are indisputable. However, even if controllers could, with the advent of enhanced ADS-B precision, reduce radar separation standards, would it be prudent to do so? Medium aircraft such as the Boeing 737 are restricted to 5nm in trail of a heavy aircraft for wake turbulence. Instances involving loss of control have occurred with aircraft operating outside of the required separation minima, which begs the question: is it wise to run aircraft any closer together than they already are? One wonders if the effect of reducing separation standards, or allowing pilots to make their own separation decisions, would even be perceptible.

Additionally, even if aircraft are able to proceed without constraint direct to their destination, they may still need to hold once they get there. The vast majority of air traffic control delays come down to runway capacity and arrival rates. An aircraft cannot take off or land while another aircraft is occupying the same runway and technological advances will never change that. Approximately four miles of in-trail spacing is required between two arriving aircraft for an aircraft to safely depart in between. To reduce separation below the three miles currently used in terminal environments would run the risk of aircraft not being able to clear the runway in time for the next arrival.
     
The suggestion that reducing separation standards could improve ATC efficiency seems akin to allowing vehicles to follow each other more closely on the highway in the hopes that traffic will move more freely. When there are not enough lanes on the bridge to accommodate lanes on the highway, a bottleneck forms and traffic congestion is the result. In aviation, most bottlenecks form when traffic demand exceeds an airport’s ability to handle arrivals and departures. The most efficient en route surveillance and separation techniques cannot improve overall efficiencies if there are not enough paved runways to accept those aircraft.

In an era of shrinking profit margins, it is incumbent upon the industry to ensure each dollar spent is being used as wisely as possible.  Modernization can facilitate a safer, more reliable ATM system, yet it remains to be seen how quickly these massive ventures in technology will return their sizeable upfront investment in terms of increased efficiency.  Rather than taking a top-down approach to air traffic management, perhaps greater savings could be realized by improving efficiency at the airport, and working from the ground up.

Part two of our two-part series on managing the skies will examine projects currently underway to increase efficiency within Canadian airspace.


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