Next Generation Air Transportation System

The Next Generation Air Transportation System (NextGen) is a new National Airspace System due for implementation across the United States in stages between 2012 and 2025. NextGen proposes to transform America’s air traffic control system from a radar-based system with radio communication to a satellite-based one. GPS technology will be used to shorten routes, save time and fuel, reduce traffic delays, increase capacity, and permit controllers to monitor and manage aircraft with greater safety margins. Radio communications will be increasingly replaced by data exchange and automation will reduce the amount of information the air crew must process at one time.

As a result of these changes, planes will be able to fly closer together, take more direct routes and avoid delays caused by airport “stacking” as planes wait for an open runway. To implement this, the Federal Aviation Administration (FAA) will undertake a wide-ranging transformation of the entire United States air transportation system. This transformation has the aim of reducing gridlock, both in the sky and at the airports. In 2003, the U.S. Congress established the Joint Planning and Development Office (JPDO) to plan and coordinate the development of the system.

Justification

The FAA estimates that increasing congestion in the air transportation system of the United States, if unaddressed, would cost the American economy $22 billion annually in lost economic activity by 2022. It also estimates that by 2018, NextGen will reduce aviation fuel consumption by 1.4 billion gallons, reduce emissions by 14 million tons and save $23 billion in costs. Each mile in the air costs an airline about $0.10-$0.15 per seat in operating expenses like flight crew and fuel. Flying directly from one airport to the next and reducing congestion around airports can reduce the time and miles spent in the air for the same trip.

Once implemented, NextGen will allow pilots and dispatchers to select their own direct flight path, rather than using a grid-like highway system. By 2020, aircraft are expected to be carrying equipment that will tell pilots exactly what their location is in relation to other aircraft, enabling planes to fly closer together safely. By providing more information to ground control and planes, planes are expected to land faster, navigate through weather better and reduce taxi times so flights and airports themselves can run more efficiently. The increased scope, volume and distribution of information is intended to help planes land faster, improve weather forecasts, automation and information sharing, as well as reduce taxi times.

Elements

NextGen consists of four elements:

1. Automatic dependent surveillance-broadcast (ADS-B). ADS-B will use Global Positioning System (GPS) satellite signals to provide air traffic controllers and pilots with much more accurate information that will help to keep aircraft safely separated in the sky and on runways. Aircraft transponders receive GPS signals and use them to determine the aircraft's precise position in the sky. These and other data are then broadcast to other aircraft and air traffic control. Once fully established, both pilots and air traffic controllers will, for the first time, see the same real-time display of air traffic, substantially improving safety. The FAA will mandate the avionics necessary for implementing ADS-B.
2. Next Generation Data Communications (Data Comm). Current communications between aircrew and air traffic control, and between air traffic controllers, are largely by voice. Initially, the introduction of data communications will provide an additional means of two-way communication for air traffic control clearances, instructions, advisories, flight crew requests and reports. With the majority of aircraft data link equipped, the exchange of routine controller-pilot messages and clearances via data link will enable controllers to handle more traffic. This will improve air traffic controller productivity, enhancing capacity and safety.
3. Next Generation Network Enabled Weather (NNEW). Seventy percent of NAS delays are attributed to weather every year. The goal of NNEW is to cut weather-related delays at least in half. Tens of thousands of global weather observations and sensor reports from ground-, airborne- and space-based sources will fuse into a single national weather information system, updated in real time. NNEW will provide a common weather picture across the national airspace system, and enable better air transportation decision making.
4. National Airspace System Voice Switch (NVS). There are currently seventeen different voice switching systems in the NAS, some in use for more than twenty years. NVS will replace these systems with a single air/ground and ground/ground voice communications system.

Implementation

The FAA is pursuing a NextGen implementation plan and has established a NextGen Advisory Committee to aid in that implementation. In 2009, the advisory committee began a collaboration with the Radio Technical Commission for Aeronautics (RTCA) Task Force, a joint government and industry group, to participate in the effort. Besides the FAA, the RTCA Task Force membership includes the Air Line Pilots Association, Air Transport Association of America, Aircraft Owners and Pilots Association, The Boeing Company, Department of Defense, GARMIN International, Honeywell International, Rockwell Collins, Stanford University, Lockheed Martin, MIT Lincoln Laboratory, Harris Corporation, NASA, National Business Aviation Association, and Raytheon.

According to the FAA, the implementation of a surface management initiative in Boston saved 5,100 gallons of aviation fuel and reduced carbon dioxide emissions by 50 tons during a period of heavy congestion. A shared surface surveillance system combined with aircraft metering techniques reduced taxi-out time by 7,000 hours a year at New York’s JFK airport and 5,000 hours a year in Memphis. Helicopters flying over the Gulf of Mexico are also using NextGen technology to manage poor weather conditions and in Colorado to navigate through dangerous mountain terrain.

There has also been a demonstration in Memphis with Delta Air Lines and FedEx. The National Air Traffic Controllers Association (NATCA) conducted a demonstration at Dallas/Fort Worth International Airport (DFW) of a new surveillance display called the Tower Flight Data Manager (TFDM) system that would present surveillance, flight data, weather, airport configuration and other information critical to controllers. Specialized Optimized Profile Descents, also known as Initial Tailored Arrivals, have moved from the demonstration phase to operational use at airports in San Francisco, Los Angeles, Miami and Denver.

In June 2010, European and American authorities reached a preliminary agreement on interoperability between their future air traffic management systems, SESAR and NextGen.

In March 2011, the FAA released the latest version of its implementation plan.

As of July 2011, JetBlue and Southwest Airlines had installed onboard equipment, partly with federal funds.

Criticism

In October 2009, U.S. Department of Transportation Inspector General Calvin Scovel and U.S. Government Accountability Office Director of Civil Aviation Issues Gerald Dillingham told Congress that the FAA faced considerable challenges in implementing a satellite-based NextGen ATC system, ranging from delays in approving new procedures and technology to skepticism among airlines regarding investment in new equipment. Testifying before the House of Representatives aviation subcommittee, Scovel warned that "the cost, schedule and benefits for NextGen are uncertain". Dillingham added that the "FAA faces cultural and organizational challenges in implementing NextGen capabilities".

Both said the agency needs to move away from developing required navigation performance (RNP) procedures for airports that merely "overlay existing routes" and toward implementing procedures that allow more direct flight paths that will increase efficiency and lower fuel burn and carbon dioxide emissions.

Dillingham said ATC system stakeholders have told GAO "that the process of approving and deploying RNP navigation procedures remains extremely slow and that the FAA's review and approval of a given original RNP design often takes years".

Noise Pollution

A feature of the NextGen program are GPS-based waypoints, which result in similar flightpaths for planes. The result of this change is that many localities are experiencing huge increases in air traffic over previously quiet areas. Complaints have risen with the added traffic and multiple municipalities have already filed suit, with more considering such a move. Metropolises affected so far include Baltimore, San Francisco, San Jose, Santa Cruz, New York, Phoenix and Culver City. The implementation of NextGen has also broken at least one historical agreement between a major airport and a municipality under one of its flight paths. Records show that 80% of recent flights over Palo Alto are in violation of two separate agreements restricting approach flights to at least 8,000 ft.

Challenges

While NextGen programs have demonstrated improvements, there are a number of ongoing and potential issues that will affect NextGen implementation.

Costs

Ongoing problems continue to threaten NextGen’s costs and timeline. A report released in October 2011 by the Government Accountability Office found the FAA has made some progress in implementation, but delays threaten to impact costs and benefits. Specifically, some acquisitions have been delayed, which has impacted the timelines of other dependent systems. The report also indicates that some key acquisitions may soon encounter delays, which can increase overall acquisition costs as well as costs to maintain current systems. For example, delays in implementing the En Route Automation Modernization (ERAM) program is projected to increase costs by $330 million, as well as an estimated $7 to $10 million per month in additional costs to continue maintaining the system that ERAM was meant to replace. In February 2012, Congress authorized $63.4 billion for FAA activities from FY12 - FY15, $11B of which is allocated to NextGen.

Program interdependencies affect midterm and longterm implementation

Due to the integrated nature of NextGen, many of its component systems are mutually dependent on one or more other systems. For instance, the delivery of ADS-B (Automatic Dependent Surveillance Broadcast) depends on ERAM because ADS-B requires the use of some ERAM functions. Additionally, ERAM is instrumental to the on-time implementation of two other crucial NextGen acquisitions— Data Communications and System Wide Information Management (SWIM). The FAA pushed the Data Communications program’s start date from September 2011 to February 2012 and delayed the SWIM-segment 2 start date from 2010 to December 2012 in part due to ERAM's delay. The long-term result of this decision is not yet known but it could delay certain SWIM capabilities as well as hinder the progress of other capabilities that depend, in turn, on the system integration that SWIM is intended to provide. Consequently, the midterm (through 2018) and long term (beyond 2018) implementation of NextGen will be affected by how well FAA manages program interdependencies.

Potential budget reductions

The delays in program implementation and budget constraints have also affected FAA capital budget planning. According to the report, congress has proposed reducing FAA’s capital budget by a total $2.8 billion (20%) for fiscal years 2012 through 2015. Most of this proposed reduction is on NextGen and NextGen-related spending, as reflected in FAA’s revised 5-year Capital Investment Plan for fiscal years 2012 through 2016. FAA will have to balance its priorities to ensure that NextGen implementation stays on course while also sustaining the current infrastructure, which is needed to prevent failures and maintain the reliability and efficiency of current operations.

Effect of delays on FAA’s ability to collaborate with Europe

The report indicates that delays in NextGen programs as well as potential budget reductions for NextGen activities, delays to NextGen programs and potential reductions in the budget for NextGen activities could delay the schedule for harmonization with Europe’s air traffic management modernization efforts (SESAR) and the realization of these benefits.

Environmental impacts

Another issue in implementing NextGen is expediting environmental reviews and developing strategies to address the environmental impacts of NextGen. A previous GAO report on environmental impacts at airports indicated that the changes in aircraft flight paths that will accompany NextGen efforts would affect some communities that were previously unaffected or minimally affected by aircraft noise and expose them to increased noise levels. These levels could trigger the need for environmental reviews, as well as raise community concerns. The report found that addressing environmental impacts can delay the implementation of operational changes, and indicated that a systematic approach to addressing these impacts and the resulting community concerns may help reduce such delays. It is worth noting that the FAA is working on developing environmental review processes that affect NextGen activities.

One of the first NextGen routes to be implemented was the "TNNIS" route emanating from New York's LaGuardia airport. The route has resulted in strong opposition from neighboring communities in the borough of Queens, NY. A 2013 New York Times article quoted area residents describing the conditions created by TNNIS as "unbearable". Largely because of TNNIS, residents successfully lobbied New York governor Andrew Cuomo to order a Part 150 noise compatibility study and establish a community aviation roundtable with the Port Authority. The FAA still refuses to conduct a full environmental impact study on the route.

Insecurity

ADS-B signals are "unencrypted and unauthenticated", leading to the tracking of USAF aircraft during combat operations.

References

 This article incorporates public domain material from the Federal Aviation Administration document "Fact Sheet".

External links

• NextGen Enters Critical Era
• The Four New Priorities of NextGen
• NextGen Procedures Go Live in Houston Metroplex