At any given moment, more than 5,000 airplanes are flying over the United States. In a single year, nearly 778 million passengers will take to the skies — more than twice the population of the U.S., and the number increases each year. Aviation is the safest form of transportation. It is 100 times safer than driving. For every 100 traffic deaths, only one aviation related fatality occurs; and the Federal Aviation Administration (FAA) is working hard to make aviation even safer.
Safety is the FAA’s primary focus. The FAA Strategic Plan FY 2019– 2022 states its mission is to provide the safest, most efficient aviation system in the world. To achieve this goal, the FAA is implementing several initiatives. The technical aspects of these efforts fall under a framework called NextGen designed to modernize the nation’s air traffic control system. NextGen began in 2003 in the VISION 100 – Century of Aviation Reauthorization Act. At its core, NextGen is a geospatial framework with satellite navigation as its backbone.
The Geospatial Data Act (GDA) became law when President Trump signed the FAA Reauthorization on Oct. 5, 2018. You might have wondered how the GDA came to be included in the bill. It makes sense in the context of technology advancements towards a smart transportation network, specifically in aviation.
The smart transportation concept integrates all forms of transportation to provide economic and environmental benefits as well as increase safety and reduce wait times and congestion. A large part of smart transportation is based on geographic information technology. The aviation component of this smart transportation initiative falls within the FAA’s authority under the overarching framework named NextGen.
NextGen is an integrated concept improving the efficiency and safety of flight operations both on the ground and in the air. The use of geospatial technology enables precision time-management for controlling air traffic. The system allows each airplane to digitally coordinate with other aircraft in the area, taking into account such things as terrain and other known hazards to safely reroute air traffic as necessary. The FAA refers to this as trajectory-based operations. Those with a knowledge of GIS will recognize it as four dimensional: it calculates direction, speed, distance and time relative to position in x-y-z, and coordinates that information with other known data. Additionally, the system uses historical flight data and predictive analytics to maximize airspace for routing air traffic such as what is experienced during the holidays.
NextGen also uses a system called Optimal Profile Descents (OPD), which allows an airplane to trim its engines and descend along a glide slope from flight level into the airport. The point at which a plane begins its descent is a geospatial calculation to determine the precise point in space for the airplane based upon its altitude, weight, glide slope and distance to the airport. The benefits of OPD are reduced engine noise, fuel savings, less carbon emissions and a positive economic impact. NextGen is an across-the-board win for the airline industry, airline passengers, the economy and the environment.
According to an interview with Michael Whitaker, former deputy administrator of the FAA who was the Chief NextGen Officer, NextGen revolutionizes aviation by enabling digital data communication. It replaces radar-based navigation and tracking with satellite-based air traffic control. The cornerstone of NextGen is the Automated Dependent Surveillance Broadcast (ADS-B) system.
ADS-B is an aviator’s version of Waze, but with a lot more information. ADS-B(out) broadcasts an airplane’s Flight ID, ICAO Code, speed and location in three-dimensional space to air traffic controllers and to everyone who is equipped with ADS-B(in). The combination of ADS-B(out) and ADS-B(in) greatly increases situational awareness for aviators. On Jan. 1, 2020, all airplanes operating in controlled airspace needed to have ADS-B(out) installed. ADS-B transforms the entire National Airspace System into a satellite-based geospatial network. It integrates multiple sources of real-time data, such as weather, pilot reports, aircraft positions, 3D airspace information, and other sources of data, which can be overlaid on top of various basemaps and terrain elevation models, allowing pilots to make more informed and safer decisions.
Switching to ADS-B opens up more capacity in already crowded skies by decreasing the required vertical and horizontal separation distances between aircraft. At Hartsfield-Jackson International Airport, the busiest airport in the world, changing to performance-based operations allowed 8 to 12 more departures per hour; and in Memphis International Airport, one of the busiest airports for cargo operations, arrivals increased by 20%.
Central to the roll-out of ADS-B was a satellite navigation system independent of GPS; GPS belongs to the Department of Defense, and for purposes of National Security, GPS is intentionally degraded — unacceptable for aviation safety. The FAA has its own constellation of navigation satellites called the Wide Area Augmentation System (WAAS), which has accuracies within 1 to 2 meters horizontally and vertically. When a localizer at the airport is connected to the WAAS system, accuracies can be reduced to less than 1 meter, enabling approaches and landings in zero visibility such as at night in dense fog.
Rune Duke, senior director of government affairs, Airspace, Air Traffic and Aviation Security for the Aircraft Owners and Pilots Association (AOPA), said that ADS-B will allow much faster update rates for air traffic controllers on the order of once every second, compared to legacy radar systems that report positions every 8 to 12 seconds. For an airplane traveling at 350 knots, that is about 1 mile. A lot can change in a mile in densely packed airspace.
If you are reading this because of your love of maps and aviation, then I highly recommend the FlightAware and ForeFlight smartphone apps. FlightAware turns the phone into an ADS-B(in) receiver showing the location and flightpath of each aircraft in the immediate area on a basemap. I sit on my back deck and watch airplanes coming and going because I live under the flightpaths for Dulles International Airport, Reagan International Airport, Leesburg Executive Airport, the Montgomery County Airpark and the TERPZ waypoint. On occasion I see helicopters flying to Camp David because I am under that flight path as well.
So, I get to see a variety of aircraft. You can select the airplane icon to see information such as aircraft type, airline, Flight ID, departing and arrival airports, altitude, and groundspeed. Even more information is available by selecting the pop-up window. This is ADS-B information. ForeFlight, on the other hand, is a pilot’s flight bag on a tablet.
In the future, ADS-B will integrate Aircraft Hazardous Areas (AHA): temporary no-fly zones due to commercial space launches. Because of ADS-B, planes will automatically reroute around the AHA, and when the AHA expires, airplanes will be routed back through the area.
ADS-B supports evolving technologies such as remote towers, another significant change to air traffic control. Remote towers allow air traffic controllers to be at a location other than the actual airfield. Remote towers use a suite of sensors mounted at the airfield, including high-definition video, thermal and night vision that can be combined with the digital information provided by ADS-B, all of which is displayed on widescreen panels in a room duplicating the experience of being at the airport and directing aircraft. This allows smaller airports that cannot afford the huge expense of building and staffing an air traffic control tower to be part of a remote tower network. One remote tower center will be able to support several airfields. Leesburg Executive Airpark recently finished successful testing of one of the first remote tower operations in the United States.
“Over the next 10 years, we are going to see logistics and transportation open up, from being limited by currently rigid road infrastructure to operating on fully flexible and responsive aerial transportation networks,” said Patrick Watson, director of business development for Animal Dynamics.
ADS-B will also support the integration of unmanned aerial systems (UAS) into the airspace, specifically unmanned cargo aircraft (UCA). In the not too distant future, carrier air fleets without pilots or aircrew will be taking to the skies. UCAs do not require crews, so there will be no need for water, toilets, sewage containment, kitchens or a cockpit (in the traditional sense). Taking those out will allow for more space in the plane to carry cargo and fuel. Plus, without crews on board, there will be no time restrictions on crew hours — planes will be able stay aloft longer and travel further. ADS-B greatly enables the success of this technology.