The disappearance of Malaysia Airlines Flight 370 last year was a reminder that even as the skies have become more congested, communications between planes and air traffic controllers is badly out of date. Most countries still rely on 1950s-era radio communications and radar technologies and have not yet fully taken advantage of the smoother air traffic control procedures that satellite-based technologies such as the global positioning system (GPS) could provide. Progress to modernize these systems has been slow, but it is happening—countries are working to replace older aviation communication technologies, and such efforts should produce noticeable benefits in the next few years. Here’s an update on these programs.
Better Air Traffic Control
Airlines flying to the U.S. are upgrading their planes’ avionics in anticipation of NextGen, a program that seeks to replace the country’s radar-based air traffic system with GPS technology. European countries have a parallel effort. In addition to providing more accurate tracking of aircraft over land, the programs are designed to cut down on delays by allowing aircraft to fly closer together so more can be in the sky or land at the same airport.
At the heart of these two plans is Automatic Dependent Surveillance-Broadcast (ADS-B), a system for tracking aircraft with GPS that is more precise and covers more ground than today’s radar technologies. It enables aircraft to broadcast their coӧrdinates every half second to a second whenever they are near a tower built to receive such signals. The tower sends the signals to air traffic controllers. By comparison, radar transmits this information every four to 15 seconds. While it may not seem like that big of a difference for any single plane, the increased precision that comes from having the technology in every plane in the air figures to greatly improve the efficiency of the entire system.
Most planes flying in U.S. and European airspace must be upgraded with transmitters and GPS receivers by 2020, and most new planes delivered before then will already have that equipment. The necessary upgrades in the U.S. alone could cost the airlines and private aircraft owners at least $4 billion, according to a September report from the U.S. Department of Transportation Office of Inspector General.
ADS-B has already provided some benefits. JetBlue is using it to fly over areas of the Gulf of Mexico that have no radar coverage, allowing planes to take shorter routes around bad weather.
Better Tracking Over Water
Airlines do not maintain continual contact with planes flying over the ocean, as the Malaysia Airlines crash and search showed. That’s because radar systems require a line of sight from the ground equipment to the aircraft, and after about 200 nautical miles, planes are out of range. Pilots do have GPS to help them see where they’re headed, but many planes flying over long stretches of water relay their position and other data back down to dispatchers only every 14 minutes or so. Using satellites to constantly relay their position and other data back down to dispatchers is too expensive with today’s systems.
However, the options for closer tracking should improve markedly within the next three years.
Among other things, sending some of this data could become cheaper and faster through a satellite link called SwiftBroadband. It is faster and cheaper than the current satellite link, so airlines can use it to get more frequent reports on a plane’s whereabouts and condition when out of radar range. Hawaiian Airlines will use it to send reports on its planes every two minutes. It also will give Hawaiian pilots a data connection fast enough for them to view real-time weather updates on their tablets in the cockpit. Typically, once pilots get airborne, they have limited ways of getting fresh information about weather and turbulence. But SwiftBroadband should let them see updated forecasts along with information about lightning, turbulence, and volcanic ash.
The ADS-B technology that NextGen will use doesn’t provide an immediate fix for better aircraft tracking over long stretches of water. That’s because this technology requires special ground-based receivers to relay GPS coördinates from aircraft transmitters to air traffic controllers. But two companies are trying to eliminate the ground infrastructure by putting receivers on satellites instead. That would enable planes flying over water to beam down position reports with the same frequency as they would on the ground.
Aireon, a subsidiary of the satellite company Iridium, says it can begin offering ADS-B from space by 2017, thanks to a network of up to 66 satellites scheduled for launch by then. Another company, Alaska-based ADS-B Technologies, is proposing that airlines use ADS-B receivers on Globalstar’s satellites. The company says the system could be fully functional by 2017.
Planes are equipped with “black boxes” that take in real-time data about the health of an aircraft’s systems and its coӧrdinates and altitude, but that information stays in the box until rescue crews can find it. Black boxes do transmit signals underwater that crews can use to locate them, but they can still be hard to find. Rescue crews needed two weeks to recover the black boxes from AirAsia Flight 8501 after it crashed in the Java Sea last month. After the crash of Air France Flight 447 in 2009, that process took nearly two years.
A new technology from Calgary, Alberta-based Flyht could stream this data to dispatchers and emergency crews as emergency events are unfolding. The unit could be fitted with backup battery power that would keep up the data flowing even after an aircraft loses electrical power. Flyht has configured the system to stream this information only when prompted by the pilot or during such events as a cabin depressurization or engine failure.
The Takeaway: The benefits of air traffic modernization programs are slowly starting to improve the aviation industry. In the meantime, pilots and airlines should soon be getting faster data links in the cockpit to transmit better information about aircraft systems and see weather information.
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