Aviation and the Environment
NextGen and Research and Development Are Keys to Reducing Emissions and Their Impact on Health and Climate Gao ID: GAO-08-706T May 6, 2008Collaboration between the federal government and the aviation industry has led to reductions in aviation emissions, but growing air traffic has partially offset these reductions. The Federal Aviation Administration (FAA), together with the National Aeronautics and Space Administration (NASA), the Environmental Protection Agency (EPA), and others, is working to increase the efficiency, safety, and capacity of the national airspace system and at the same time reduce aviation emissions, in part, by transforming the current air traffic control system to the Next Generation Air Transportation System (NextGen). This effort involves new technologies and air traffic procedures that can reduce aviation emissions and incorporates research and development (R&D) on emissions-reduction technologies. Reducing aviation emissions is important both to minimize their adverse health and environmental effects and to alleviate public concerns about them that could constrain the expansion of airport infrastructure and aviation operations needed to meet demand. This testimony addresses (1) the scope and nature of aviation emissions, (2) the status of selected key federal efforts to reduce aviation emissions, and (3) next steps and challenges in reducing aviation emissions. The testimony updates prior GAO work with FAA data, literature reviews, and interviews with agency officials, industry and environmental stakeholders, and selected experts.
Aviation contributes a modest but growing proportion of total U.S. emissions, and these emissions contribute to adverse health and environmental effects. Aircraft and airport operations, including those of service and passenger vehicles, emit ozone and other substances that contribute to local air pollution, as well as carbon dioxide and other greenhouse gases that contribute to climate change. EPA estimates that aviation emissions account for less than 1 percent of local air pollution nationwide and about 2.7 percent of U.S. greenhouse gas emissions, but these emissions are expected to grow as air traffic increases. Two key federal efforts, if implemented effectively, can help to reduce aviation emissions--NextGen initiatives in the near term and research and development over the longer term. For example, NextGen technologies and procedures, such as satellite-based navigation systems, should allow for more direct routing, which could improve fuel efficiency and reduce carbon dioxide emissions. Federal research and development efforts--led by FAA and NASA in collaboration with industry and academia--have achieved significant reductions in aircraft emissions through improved aircraft and engine technologies, and federal officials and aviation experts agree that such efforts are the most effective means of achieving further reductions in the longer term. Federal R&D on aviation emissions also focuses on improving the scientific understanding of aviation emissions and developing lower-emitting aviation fuels. Next steps in reducing aviation emissions include managing NextGen initiatives efficiently; deploying NextGen technologies and procedures as soon as practicable to realize their benefits, including lower emissions levels; and managing a decline in R&D funding, in part, by setting priorities for R&D on NextGen and emissions-reduction technologies. Challenges in reducing aviation emissions include designing aircraft that can simultaneously reduce noise and emissions of air pollutants and greenhouse gases; encouraging financially stressed airlines to purchase more fuel-efficient aircraft and emissions-reduction technologies; addressing the impact on airport expansion of more stringent EPA air quality standards and growing public concerns about the effects of aviation emissions; and responding to proposed domestic and international measures for reducing greenhouse gases that could affect the financial solvency and competitiveness of U.S. airlines.
GAO-08-706T, Aviation and the Environment: NextGen and Research and Development Are Keys to Reducing Emissions and Their Impact on Health and Climate
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Testimony Before the Subcommittee on Aviation, Committee on
Transportation and Infrastructure, House of Representatives:
United States Government Accountability Office:
GAO:
For Release on Delivery:
Expected at 2:00 p.m. EDT:
Tuesday, May 6, 2008:
Aviation And The Environment:
NextGen and Research and Development Are Keys to Reducing Emissions and
Their Impact on Health and Climate:
Statement of Gerald L. Dillingham, Ph.D.
Director, Physical Infrastructure Issues:
GAO-08-706T:
GAO Highlights:
Highlights of GAO-08-706T, a testimony before the Subcommittee on
Aviation, Committee on Transportation and Infrastructure, House of
Representatives.
Why GAO Did This Study:
Collaboration between the federal government and the aviation industry
has led to reductions in aviation emissions, but growing air traffic
has partially offset these reductions. The Federal Aviation
Administration (FAA), together with the National Aeronautics and Space
Administration (NASA), the Environmental Protection Agency (EPA), and
others, is working to increase the efficiency, safety, and capacity of
the national airspace system and at the same time reduce aviation
emissions, in part, by transforming the current air traffic control
system to the Next Generation Air Transportation System (NextGen). This
effort involves new technologies and air traffic procedures that can
reduce aviation emissions and incorporates research and development
(R&D) on emissions-reduction technologies. Reducing aviation emissions
is important both to minimize their adverse health and environmental
effects and to alleviate public concerns about them that could
constrain the expansion of airport infrastructure and aviation
operations needed to meet demand.
This testimony addresses (1) the scope and nature of aviation
emissions, (2) the status of selected key federal efforts to reduce
aviation emissions, and (3) next steps and challenges in reducing
aviation emissions. The testimony updates prior GAO work with FAA data,
literature reviews, and interviews with agency officials, industry and
environmental stakeholders, and selected experts.
What GAO Found:
Aviation contributes a modest but growing proportion of total U.S.
emissions, and these emissions contribute to adverse health and
environmental effects. Aircraft and airport operations, including those
of service and passenger vehicles, emit ozone and other substances that
contribute to local air pollution, as well as carbon dioxide and other
greenhouse gases that contribute to climate change. EPA estimates that
aviation emissions account for less than 1 percent of local air
pollution nationwide and about 2.7 percent of U.S. greenhouse gas
emissions, but these emissions are expected to grow as air traffic
increases.
Two key federal efforts, if implemented effectively, can help to reduce
aviation emissions”NextGen initiatives in the near term and research
and development over the longer term. For example, NextGen technologies
and procedures, such as satellite-based navigation systems, should
allow for more direct routing, which could improve fuel efficiency and
reduce carbon dioxide emissions. Federal research and development
efforts”led by FAA and NASA in collaboration with industry and
academia”have achieved significant reductions in aircraft emissions
through improved aircraft and engine technologies, and federal
officials and aviation experts agree that such efforts are the most
effective means of achieving further reductions in the longer term.
Federal R&D on aviation emissions also focuses on improving the
scientific understanding of aviation emissions and developing lower-
emitting aviation fuels.
Next steps in reducing aviation emissions include managing NextGen
initiatives efficiently; deploying NextGen technologies and procedures
as soon as practicable to realize their benefits, including lower
emissions levels; and managing a decline in R&D funding, in part, by
setting priorities for R&D on NextGen and emissions-reduction
technologies. Challenges in reducing aviation emissions include
designing aircraft that can simultaneously reduce noise and emissions
of air pollutants and greenhouse gases; encouraging financially
stressed airlines to purchase more fuel-efficient aircraft and
emissions-reduction technologies; addressing the impact on airport
expansion of more stringent EPA air quality standards and growing
public concerns about the effects of aviation emissions; and responding
to proposed domestic and international measures for reducing greenhouse
gases that could affect the financial solvency and competitiveness of
U.S. airlines.
Figure: Sources of Aviation Emissions:
[See PDF for image]
This figure is a photograph of an aircraft parked at a terminal gate.
Source: FAA.
[End of figure]
To view the full product, including the scope and methodology, click on
[hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-08-706T]. For more
information, contact Gerald L. Dillingham at (202) 512-2834 or
dillinghamg@gao.gov.
[End of section]
Mr. Chairman and Members of the Subcommittee:
I appreciate the opportunity to testify before you on aviation
emissions, one of the key sources of concern about the environmental
effects of aviation. Over the past 30 years, the federal government,
the aviation industry, and other private parties have worked
collaboratively to achieve steady reductions in aircraft emissions.
[Footnote 1] Nevertheless, increases in air traffic, which have
enhanced the nation's productivity and mobility, have partially offset
these reductions, as more flights have produced more emissions and
congestion has led to flight delays. According to the Federal Aviation
Administration (FAA), this growth in air traffic will continue, with
the number of flights increasing 20 percent by 2015 and 60 percent by
2030.[Footnote 2] In light of these developments, concerns about the
environmental effects of aviation emissions have persisted. Moreover,
better scientific understanding of the potential health effects of
certain aviation emissions and their contribution to climate change has
intensified the public's concerns.
To accommodate the expected growth in air traffic, FAA is leading a
multipronged, multiagency effort to increase the efficiency, safety,
and capacity of the national airspace system. This effort includes
transforming the current air traffic control system into the Next
Generation Air Transportation System (NextGen)[Footnote 3] and will
require airport and runway expansion. The NextGen initiative
incorporates research and development (R&D) on emissions-reduction
technologies, alternative fuels, and cleaner and quieter air traffic
management procedures. This R&D is necessary both to meet anticipated
domestic and international environmental standards and to reduce the
environmental impact of aviation. Meeting environmental standards can
limit the adverse effects of aviation emissions on air quality and
climate, and addressing public concerns about aviation emissions is
necessary to avoid constraints on the expansion of aviation operations
and airport infrastructure planned under NextGen.[Footnote 4]
Under the National Environmental Policy Act of 1969, agencies evaluate
the likely environmental effects of projects they are proposing using
an environmental assessment or, if the projects likely would
significantly affect the environment, a more detailed environmental
impact statement.[Footnote 5] FAA typically carries out one of these
evaluations for federally financed airport construction projects,
including the construction of federally subsidized runways. In
addition, under the Clean Air Act's conformity provision, no federal
agency may approve or provide financial assistance for any activity
that does not conform to an applicable state implementation
plan.[Footnote 6] Therefore, FAA must evaluate whether a proposed
federal action associated with an airport project conforms with the
applicable state implementation plan before approving or funding the
project.[Footnote 7] In addition, the Clean Air Act mandates standards
for mobile sources of emission, such as aircraft and the equipment that
service them at airports. EPA sets emissions standards for aircraft and
has chosen to adopt international emissions standards for aircraft set
by the International Civil Aviation Organization (ICAO).[Footnote 8]
As requested, my testimony today focuses on aviation emissions. It will
address the following questions: (1) What are the scope and nature of
aviation emissions? (2) What is the status of selected key federal
efforts to address aviation emissions? and (3) What are some next steps
and major challenges for the federal government, the aviation industry,
and Congress related to aviation emissions? My statement is based on
previous GAO reports[Footnote 9] updated with a synthesis of recent
empirical literature and interviews with officials from FAA, the
National Aeronautics and Space Administration (NASA), and the U.S.
Environmental Protection Agency (EPA); representatives of aviation
industry and environmental associations, and selected aviation
emissions experts.[Footnote 10] We balanced the selection of these
experts to capture the views of the many different groups involved in
aviation emissions reduction efforts and NextGen. We conducted our work
from March to May 2008 in accordance with generally accepted government
auditing standards. Those standards require that we plan and perform
the study to obtain sufficient, appropriate evidence to provide a
reasonable basis for our findings and conclusions based on our study
objectives. We believe that the evidence obtained provides a reasonable
basis for our findings and conclusions based on our study objectives.
Summary:
Currently, aviation contributes a modest proportion of total emissions
in the United States, but its share could increase in the future, and
aviation emissions can have a detrimental effect on health and the
environment. Aircraft are the primary source of aviation emissions, but
airport operations, including those of service and passenger vehicles,
also produce emissions. Together, aircraft operations in the vicinity
of the airport and other airport sources emit nitrogen oxides, which
lead to the formation of ground-level ozone (also known as smog), and
other substances that contribute to local air pollution, as well as
carbon dioxide and other greenhouse gases that rise into the atmosphere
and contribute to climate change. Aircraft operations in the upper
atmosphere are, however, the primary aviation-related source of
greenhouse gas emissions. Currently, according to EPA estimates,
aviation emissions account for less than 1 percent of local air
pollution nationwide and about 2.7 percent of U.S. greenhouse gas
emissions. This proportion is, however, expected to grow with projected
increases in air traffic, despite expected improvements in fuel
efficiency. Notably, according to FAA, emissions of nitrogen oxides
from aviation sources will increase by over 90 percent by 2025 if not
addressed. This increase is likely to increase ozone, which aggravates
respiratory ailments. Increases in air traffic also mean increases in
carbon dioxide emissions and increases in aviation's contribution to
climate change, according to the International Panel on Climate Change
(IPCC).
Two key federal efforts, if implemented effectively, can help to reduce
aviation emissions--near-term NextGen initiatives and R&D over the
longer term to fully enable NextGen and reduce aircraft emissions. Some
NextGen technologies and procedures, such as satellite-based navigation
systems, should allow for more direct routing, which could improve fuel
efficiency and reduce carbon dioxide emissions. According to FAA, the
full implementation of NextGen could reduce greenhouse gas emissions
from aircraft by up to 12 percent by 2025. Federal R&D efforts--led
primarily by FAA and NASA and often conducted in collaboration with
industry and academia--have achieved significant reductions in aircraft
emissions over the last 30 years, and FAA and NASA officials and
aviation experts agree that such efforts are the most effective means
of achieving further reductions in the longer term. As part of the a
national plan for aeronautics R&D, issued by the White House Office of
Science and Technology Policy, the federal government supports a
comprehensive approach to R&D on aviation emissions involving FAA,
NASA, and other federal agencies that is intended both to improve
scientific understanding of the impact of aviation emissions and to
develop new technologies, fuels, and air traffic management approaches.
Better understanding of the nature and impact of aviation emissions can
inform the development of lower-emitting alternative fuels, more
efficient air traffic management technologies and procedures, and more
fuel-efficient aircraft engines.
Reducing aviation emissions includes steps that FAA and others can take
to move the implementation of NextGen forward and to support R&D on
NextGen and emissions-reduction technologies, as well as technical,
financial, and regulatory challenges facing the federal government, the
aviation industry, and Congress. One step for FAA is to ensure the
efficiency of NextGen's management by, for example, addressing
congressional leaders' and stakeholders' concerns about the program's
management structure and authority. Another step for FAA is to further
deploy, as soon as practicable, NextGen technologies and procedures,
such as the more efficient takeoff and landing procedures now in use at
a few airports, to realize their benefits and lower emissions levels. A
third step, for FAA and NASA, is managing a decline in federal funding
for aeronautics research, the research category that includes work on
aviation emissions, new aircraft and engine technologies, and
alternative fuels. As a result of this decline, NASA is now sometimes
developing technologies to a lower maturity level than in the past, and
the technologies are less ready for manufacturers to adopt them. The
administration's reauthorization bill for FAA seeks some additional
funding for an initiative that could lead to the earlier maturation of
certain emissions-reduction technologies, but according to some
experts, increased funding of the initiative could increase the
probability of success and decrease the time needed to achieve that
success. Challenges in reducing aviation emissions for the federal
government, the aviation industry, and Congress include designing
aircraft that can simultaneously reduce noise and emissions of air
pollutants and greenhouse gases; encouraging financially stressed
airlines to purchase more fuel-efficient aircraft and emissions-
reduction technologies; addressing the impact on airport expansion of
more stringent EPA air quality standards and growing public concerns
about effects of aviation emissions; and responding to proposed
domestic and international measures for reducing greenhouse gases that
could affect the financial solvency and competitiveness of U.S.
airlines.
Aviation's Small but Growing Proportion of Total Emissions Contributes
to Health and Environmental Effects:
Aviation-related activities contribute to local air pollution and
produce greenhouse gases that cause climate change. Aircraft account
for about 70 to 80 percent of aviation emissions, producing emissions
that mainly affect air quality below 3,000 feet and increase greenhouse
gases at higher altitudes. At ground level, airport operations,
including those of motor vehicles[Footnote 11] traveling to and from
the airport, ground service equipment,[Footnote 12] and stationary
sources such as incinerators and boilers, also produce emissions.
Together, aircraft operations in the vicinity of the airport and other
airport sources produce emissions such as carbon monoxide, sulfur
oxides, particulate matter, nitrogen oxides, unburned hydrocarbons,
hazardous air pollutants,[Footnote 13] and ozone[Footnote 14] that
contribute to air pollution. In addition, these sources emit carbon
dioxide and other greenhouse gases that contribute to climate change,
but aircraft operations in the upper atmosphere are the primary source
of aviation-related greenhouse gases. Carbon dioxide is both the
primary aircraft emission and the primary contributor to climate
change. It survives in the atmosphere for over 100 years. Furthermore,
other gases and particles emitted by aircraft--including water vapor,
nitrogen oxides, soot, contrails,[Footnote 15] and sulfate--can also
have an impact on climate, but the magnitude of this impact is unknown,
according to FAA. Figure 1 illustrates aviation's impact on air quality
and climate.
Figure 1: Environmental Effects of Aviation Emissions and Noise:
[See PDF for image]
This figure is an illustration of environmental effects of aviation
emissions and noise. The following information is depicted:
Ground level to 3,000 feet: Airports produce:
Nitrogen oxides, O3, particulates and noise; effect local air quality
and noise pollution.
Troposphere (3,000 to 40,000 feet): Aircraft produce:
CO2, NOx, H2O, and particulates; effect on climate change.
Stratosphere (above 40,000 feet): Aircraft produce:
NOx, halogens; effect on ozone layer change.
Source: GAO.
[End of figure]
Currently, aviation accounts for a small portion of air pollutants and
greenhouse gas emissions. Specifically, aviation emissions represent
less than 1 percent of air pollution nationwide, but their impact on
air quality could be higher in the vicinity of airports. In addition,
aviation accounts for about 2.7 percent of the total U.S. contribution
of greenhouse gas emissions, according to the Department of
Transportation's Center for Climate Change and Environment. A 1999
study by the United Nations' Intergovernmental Panel on Climate Change
(IPCC) estimated that global aircraft emissions generally accounted for
approximately 3.5 percent of the warming generated by human
activity.[Footnote 16]
As air traffic increases, aviation's contribution to air pollution and
climate change could also grow, despite ongoing improvements in fuel
efficiency, particularly if other sectors achieve significant
reductions. In addition, aviation's impact on air quality is changing
as more fuel-efficient, quieter aircraft engines are placed in service.
While new aircraft engine technologies have reduced fuel consumption,
noise, and emissions of most pollutants, they have not achieved the
same level of reductions in nitrogen oxide emissions, which contribute
to ozone formation. According to FAA, nitrogen oxide emissions from
aviation will increase by over 90 percent by 2025 without improvements
in aircraft emissions technologies and air traffic management, and
emissions of other air pollutants will also increase, as shown in
figure 2. Additionally, aviation's greenhouse gas emissions and
potential contribution to climate change is expected to increase. IPCC
has estimated that aircraft emissions are likely to grow by 3 percent
per year, outpacing the emissions reductions achieved through
technological improvements. Furthermore, as emissions from other
sources decline, aviation's contribution to climate change may become
proportionally larger, according to FAA. Alternative fuels are not yet
available in sufficient quantities for jet aircraft, as they are for
some other uses, and therefore aviation cannot yet adopt this approach
to reduce its greenhouse gas emissions (see discussion below on U.S.
efforts to develop alternative fuels for aviation).
Figure 2: FAA Analysis of Growth in Aviation Related Pollutants by
2025:
[See PDF for image]
This figure is a vertical bar graph depicting the following data:
FAA Analysis of Growth in Aviation Related Pollutants by 2025:
Pollutant: Hydrocarbons;
Percent increase: 75%.
Pollutant: Carbon monoxide;
Percent increase: 70%;
Pollutant: Nitrogen oxides;
Percent increase: 90%.
Pollutant: Sulfur oxides;
Percent increase: 85%.
Source: FAA.
Note: According to FAA, the increases in aviation-related pollutants
are baseline forecasts that do not account for potential improvements
in aircraft technology and air traffic management.
[End of figure]
Aviation emissions, like other combustible emissions, include
pollutants that affect health. While it is difficult to determine the
health effects of pollution from any one source, the nitrogen oxides
produced by aircraft engines contribute to the formation of ozone, the
air pollutant of most concern in the United States and other
industrialized countries. Ozone has been shown to aggravate respiratory
ailments. A National Research Council panel recently concluded that
there is strong evidence that even short-term exposure to ozone is
likely to contribute to premature deaths of people with asthma, heart
disease, and other preexisting conditions. With improvements in
aircraft fuel efficiency and the expected resulting increases in
nitrogen oxide emissions, aviation's contribution to ozone formation
may increase. In addition, aviation is associated with other air
pollutants, such as hazardous air pollutants, including benzene and
formaldehyde, and particulate matter, all of which can adversely affect
health. Data on emissions of hazardous air pollutants in the vicinity
of airports are limited, but EPA estimates that aviation's production
of these pollutants is small relative to other sources, such as on-road
vehicles. Nevertheless, according to EPA, there is growing public
concern about the health effects of the hazardous air pollutants and
particulate matter associated with aviation emissions. See appendix I
for more detailed information on the health and environmental effects
of aviation emissions.
Carbon dioxide and other greenhouse gas emissions from aircraft
operations in the atmosphere, together with ground-level aviation
emissions that gradually rise into the atmosphere, contribute to global
warming and climate change. IPCC's most recent report[Footnote 17]
documents mounting evidence of global warming and projects the
potential catastrophic effects of climate change. As figure 6 shows,
climate change affects precipitation, sea levels, and winds as well as
temperature, and these changes in turn will increasingly affect
economies and infrastructure around the world.
Figure 3: Concerns about the Effects of Climate Change:
[See PDF for image]
This figure is an illustration of concerns about the effects of climate
change. The following information is depicted:
Climate Change:
* Temperature;
* Precipitation and severe weather;
* Rising sea levels;
* Winds.
Possible effects:
* Health Impacts;
* Agricultural impacts;
* Forest impacts;
* Water resource impacts;
* Coastal area impacts;
* Ecosystem impacts;
* Economic and infrastructure impacts.
Source: EPA and FAA.
[End of figure]
Key Federal Efforts to Address Aviation Emissions Include Near-Term
Operational Changes and Longer-Term R&D Initiatives:
Two key federal efforts, if implemented effectively, can help to reduce
aviation emissions--near-term NextGen initiatives and an array of R&D
programs over the longer term to fully enable NextGen and to reduce
aircraft emissions. The NextGen initiatives are primarily intended to
improve the efficiency of the aviation system so that it can handle
expected increases in air traffic, but these initiatives can also help
reduce aviation emissions. In addition, the federal government, led by
FAA and NASA, has longer-term R&D programs in place to improve the
scientific understanding of the impact of aviation emissions in order
to inform decisions about emissions-reduction strategies, explore
potential emissions-reducing alternative fuels, and develop NextGen and
aircraft emissions-reduction technologies.
NextGen Initiatives Have the Potential to Help Reduce Emissions:
Technologies and procedures that are being developed as part of NextGen
to improve the efficiency of flight operations can also reduce aircraft
emissions. According to FAA, the implementation of NextGen could reduce
greenhouse gas emissions from aircraft by up to 12 percent. One NextGen
technology, considered a centerpiece of NextGen, is the Automatic
Dependent Surveillance-Broadcast (ADS-B) satellite aircraft navigation
system. ADS-B is designed, along with other navigation technologies, to
enable more precise control of aircraft during en route flight,
approach, and descent. ADS-B will allow for closer and safer
separations between aircraft and more direct routing, which will
improve fuel efficiency and reduce carbon dioxide emissions. This
improved control will also facilitate the use of air traffic control
procedures that will reduce communities' exposure to aviation emissions
and noise. One such procedure, Continuous Descent Arrivals (CDA),
allows aircraft to remain at cruise altitudes longer as they approach
destination airports, use lower power levels, and thereby lower
emissions and noise during landings. Figure 3 shows how CDA compares
with the current step-down approach to landing, in which aircraft make
alternate short descents and forward thrusts, which produce more
emissions and noise than continuous descents. A limited number of
airports have already incorporated CDA into their operations. For
example, according to officials from Los Angeles International Airport,
nearly 25 percent of landings at their airport use CDA procedures in
one of the airport's standard terminal approaches. In addition, United
Parcel Service plans to begin using a nighttime CDA procedure, designed
and tested at the Louisville International Airport, for its hub
operations.
Figure 4: Comparison of CDA and Current Step-Down Approach:
[See PDF for image]
This figure is an illustration of the comparison of CDA and current
step-down approach. The illustration shows the relative position of the
aircraft to the runway using the two techniques.
Source: Naverus and AVTECH.
Note: Continuous Descent Arrivals keep aircraft higher for longer and
have them descend at near-idle power to touchdown. Optimal profiles are
not always possible, especially at busy airports.
[End of figure]
Two closely associated NextGen initiatives, Area Navigation (RNAV) and
Required Navigation Performance (RNP), have the potential to modify the
environmental impact of aviation by providing enhanced navigational
capability to the pilot. RNAV equipment can compute an airplane's
position, actual track, and ground speed, and then provide meaningful
information on the route of flight selected by the pilot. RNP will
permit the airplane to descend on a precise route that will allow it to
avoid populated areas, reduce its consumption of fuel, and lower its
emissions of carbon dioxide and nitrogen oxides.[Footnote 18] See
figure 4. Currently, over 350 RNAV/RNP procedures are available at 54
airports, including Dallas/Fort Worth, Miami International, Washington
Dulles, and Atlanta Hartsfield.
Figure 5: Comparison of RNP and Current Step-Down Approach:
[See PDF for image]
This figure is an illustration of the comparison of RNP and current
step-down approach. The illustration shows the relative position of the
aircraft to the runway using the two techniques. In RNP, the idle
thrust descent produces less emissions, less fuel used and less noise.
Source: Naverus and AVTECH.
Note: An RNP approach and path allows for idle-thrust, continuous
descent instead of today's step-down approaches with vectors. RNP
precision and curved-approach flexibility can shift flight paths to
avoid populated areas.
[End of figure]
Still another NextGen initiative, High-Density Terminal and Airport
Operations, is intended to improve the efficiency of aircraft
operations at busy airports, and, in the process, reduce emissions. At
high-density airports, the demand for access to runways is high, and
arrivals and departures take place on multiple runways. The combination
of arrivals, departures, and taxiing operations may result in
congestion, which in turn produces delays, emissions, and noise as
aircraft wait to take off and land. Under the High-Density Terminal and
Airport Operations initiative, which FAA has just begun to implement,
aircraft arriving and departing from different directions would be
assigned to multiple runways and safely merged into continuous flows
despite bad weather and low visibility. To guarantee safe separation,
these airports would need enhanced navigation capabilities and
controllers with access to increased automation. Under this initiative,
aircraft would also move more efficiently on the ground, using
procedures that are under development to reduce spacing and separation
requirements and improve the flow of air traffic into and out of busy
metropolitan airspace. More efficient aircraft movement would increase
fuel efficiency and reduce emissions and noise. Although the
implementation of this initiative is in the early stages, FAA has
identified the R&D needed to move it forward.
Technologies and procedures planned for NextGen should also help
improve the efficiency of flights between the United States and other
nations, further reducing emissions, particularly of greenhouse gases.
A test program scheduled to begin in the fall of 2008, known as the
Atlantic Interoperability Initiative to Reduce Emissions (AIRE),
sponsored by FAA and the European Commission, Boeing, and Airbus, will
involve gate-to-gate testing of improved procedures on the airport
surface, during departures and arrivals, and while cruising over the
ocean. Some of the procedures to be tested will use technologies such
as ADS-B. A similar effort--the Asia and South Pacific Initiative to
Reduce Emissions (ASPIRE)--was launched earlier this year, involving
the United States, Australia, and New Zealand.
Federal R&D Focuses on Long-Term Approaches to Addressing Aviation
Emissions:
We have previously reported[Footnote 19] that the federal government
and industry have achieved significant reductions in some aircraft
emissions, such as carbon dioxide, through past R&D efforts, and
federal officials and aviation experts agree that such efforts are the
most effective means of achieving further reductions in the longer
term[Footnote 20]. As part of the a national plan for aeronautics R&D,
issued by the White House Office of Science and Technology Policy, the
federal government supports a comprehensive approach to R&D on aviation
emissions that involves FAA, NASA, and other federal agencies.
According to FAA, this approach includes efforts to improve the
scientific understanding of the nature and impact of aviation emissions
and thereby inform the development of more fuel-efficient aircraft, of
alternative fuels that can reduce aircraft emissions, and of air
traffic management technologies that further improve the efficiency of
aviation operations. NASA, industry, and academia are important
partners in these efforts. Notably, however, the development of
breakthrough technologies, such as highly fuel-efficient aircraft
engines that emit fewer greenhouse gases and air pollutants, is
expensive and can take a long time, both to conduct the research and to
implement the new technologies in new aircraft designs and introduce
these new aircraft into the fleet. Successfully developing these
technologies also requires the support and cooperation of stakeholders
throughout the aviation industry.
FAA Supports Research on Improving the Scientific Understanding of
Aviation Emissions and on Alternative Fuels:
Improving the scientific understanding of aviation emissions can help
guide the development of approaches to reducing emissions by improving
aircraft manufacturers' and operators' and policy makers' ability to
assess the environmental benefits and costs of alternative policy
measures. Such an assessment can then lead to the selection of the
alternative that will achieve the greatest net environmental benefits.
For example, one technology might greatly increase fuel efficiency, but
produce higher nitrogen oxide emissions than another, somewhat less
fuel-efficient technology. Overall, a cost benefit analysis might
indicate that the less fuel-efficient technology would produce greater
net benefits for the environment.
FAA currently supports several recent federal efforts to better
quantify aviation emissions and their impact through improvements in
emissions measurement techniques and modeling capability. One of these
efforts is FAA's Partnership for Air Transportation and Emissions
Reduction (PARTNER) Center of Excellence.[Footnote 21] Created in 2003,
PARTNER carries on what representatives of airlines, aircraft and
engine manufacturers, and experts in aviation environmental research
have described as a robust research portfolio. This portfolio includes
efforts to measure aircraft emissions and to assess the human health
and welfare risks of aviation emissions and noise. For example,
researchers are developing an integrated suite of three analytical
tools--the Environmental Design Space, the Aviation Environmental
Design Tool, and the Aviation Environmental Portfolio Management Tool -
that can be used to identify interrelationships between noise and
emissions. Data from these three tools, together with the Aviation
Environmental Design tool being developed by the Volpe National
Transportation Systems Center and others, will allow for assessing the
benefits and costs of aviation environmental policy options. Another
R&D initiative, the Airport Cooperative Research Program
(ACRP),[Footnote 22] conducts applied research on aviation emissions
and other environmental issues facing airports. The program is managed
by the National Academies of Science through its Transportation
Research Board under a contract with FAA, which provided $10 million
for the program in both 2007 and 2008 and is seeking to increase these
investments through its reauthorization to specifically focus on
aviation environmental issues. Several of the emissions-related
projects undertaken through ACRP have concentrated on developing
methods to measure particulate matter and hazardous air pollutants at
airports in order to identify the sources of these pollutants and
determine whether their levels could have adverse health effects. FAA
has also developed an Aviation Emissions Characterization roadmap to
provide a systematic process to enhance understanding of aviation's air
quality emissions, most notably particulate matter and hazardous air
pollutants. In addition, FAA, in conjunction with NASA and the National
Oceanic and Atmospheric Administration, launched the Aviation Climate
Change Research Initiative to develop the scientific understanding
necessary for informing efforts to limit or reduce aviation greenhouse
gas emissions.
Another effort, the Commercial Aviation Alternative Fuels Initiative
(CAAFI),[Footnote 23] led by FAA, together with airlines, airports, and
manufacturers, is intended to identify and eventually develop
alternative fuels for aviation that could lower emissions of greenhouse
gases, and other pollutants; increase fuel efficiency; and reduce U.S.
dependence on foreign oil. CAAFI supports research on low-carbon fuel
from sources such as plant oils, algae, and biomass that are as safe as
petroleum-based fuel and compare favorably in terms of environmental
impact. Part of the research will involve assessing the environmental
impact of alternative fuels to determine whether their use could reduce
emissions of pollutants that affect climate and air quality. The
research will also assess the impact of producing these fuels on the
overall carbon footprint. The CAAFI sponsors have set goals for
certifying a 50 percent synthetic fuel for aviation use in 2008, a 100
percent synthetic fuel for use by 2010, and a biofuel made from
renewable resources such as palm, soy, or algae oils. As part of CAAFI,
Virgin Atlantic Airlines, together with Boeing, has tested a blend of
kerosene (normal jet fuel) and biofuels in a flight from London to
Amsterdam, and Continental, in association with Boeing and jet engine
manufacturer General Electric, is planning a similar test in 2009.
NASA Conducts Fundamental Aeronautics R&D in Support of NextGen,
Including Efforts That Can Help Lower Emissions:
NASA has devoted a substantial portion of its aeronautical R&D program
to the development of technologies critical to the implementation of
NextGen, as well as new aircraft and engine technologies, both of which
can help reduce aviation emissions.
NASA has three main aeronautics research programs - Fundamental
Aeronautics, Aviation Safety, and Airspace Systems - each of which
contributes directly and substantially to NextGen. For example, the
Airspace Systems program supports research on air traffic management
technologies for NextGen, and the Fundamental Aeronautics program
focuses on removing environmental and performance barriers, such as
noise and emissions, that could constrain the capacity enhancements
needed to accommodate projected air traffic increases. Appendix II
describes in more detail how NASA's aeronautics R&D programs support
the implementation of NextGen.
NASA also works with aircraft and aircraft engine manufacturers to
increase fuel efficiency and reduce emissions. Their efforts have
contributed to a number of advancements in aircraft engine and airframe
technology, and NASA's R&D on emissions-reduction technologies
continues. NASA has set technology-level goals for reducing greenhouse
gases, nitrogen oxides, and noise, which have become part of the U.S.
National Aeronautics Plan. For example, the plan includes a goal for
developing technologies that could reduce nitrogen oxide emissions
during landings and takeoffs by 70 percent[Footnote 24] below the ICAO
current standard. The plan also sets a goal of increasing fuel
efficiency (and thereby decreasing greenhouse gases emissions) by 33
percent. These technologies would be incorporated in the next
generation of aircraft, which NASA refers to as N+1,[Footnote 25] by
2015. However, as NASA officials note, these goals must be viewed
within the context that each of the goals can be fully met only if it
is the only goal. For example, the goal for reducing nitrogen oxides
can be fully achieved only at the expense of the goals for lowering
greenhouse gas emissions and noise, because it is technologically
challenging to design aircraft that can simultaneously reduce all of
these environmental impacts.
For the longer term (2020), NASA is focusing on developing tools and
technologies for use in the design of advanced hybrid-wing body
aircraft, the following generation of aircraft, or N+2. Emissions from
these aircraft would be in the range of 80 percent below the ICAO
standard for nitrogen oxide emissions during landings and takeoffs, and
fuel consumption would be 40 percent less than for current aircraft.
The U.S. aircraft and engine manufacturing industry has also set goals
for reducing aircraft emissions in the engines the industry plans to
produce. According to the Aerospace Industries Association, which
represents this industry, its members have set a goal of reducing
carbon dioxide emissions by 15 percent in the next generation of
aircraft while continuing to significantly reduce nitrogen oxide
emissions and noise.
The development of aircraft technologies such as those that NASA is
currently working on to reduce emissions can take a long time, and it
may be years before the technologies are ready to be incorporated into
new aircraft designs. According to FAA, the development process
generally takes 12 to 20 years. For example, the latest Pratt and
Whitney engine, the geared turbofan, which is expected to achieve
significant emissions and noise reductions, took 20 years to develop.
Several Steps Can Be Taken to Help Reduce Aviation Emissions, but
Challenges Remain to Be Addressed:
Reducing aviation emissions includes steps that FAA and others can take
to move the implementation of NextGen forward and support R&D on
NextGen and emissions-reduction technologies, as well as technical,
financial, regulatory challenges facing the federal government, the
aviation industry, and Congress.
Expediting the Implementation of NextGen Can Help Reduce Aviation
Emissions:
Implementing NextGen expeditiously is essential to handle the projected
growth in air traffic efficiently and safely, and in so doing, help to
reduce aircraft emissions. Steps to advance NextGen's implementation
include management improvements and the deployment of available NextGen
components.
Management Improvements Can Move NextGen Forward More Efficiently:
Several management actions are important to advance the implementation
of NextGen. One such action is to establish a governance structure
within FAA that will move NextGen initiatives forward efficiently and
effectively. FAA has begun to establish a governance structure for
NextGen, but it may not be designed to give NextGen initiatives
sufficient priority to ensure the system's full implementation by 2025.
Specifically, FAA's implementation plan for NextGen is called the
Operational Evolution Partnership (OEP). The manager responsible for
OEP is one of nine Vice Presidents who report to the Chief Operating
Officer (COO) of FAA's Air Traffic Organization (ATO), who reports
directly to the FAA Administrator. While the manager responsible for
OEP is primarily responsible for implementing NextGen, other Vice
Presidents are responsible for NextGen-related activities in their
designated areas. In addition, the FAA managers responsible for
airports and aviation safety issues are Associate Administrators who
report through the Deputy FAA Administrator to the FAA Administrator.
Some of the activities for which these Associate Administrators are
responsible are critical to NextGen's implementation, yet there is no
direct line of authority between the OEP manager and these activities.
Some congressional leaders and other stakeholders, including aviation
industry representatives and aviation experts, view FAA's management
structure for NextGen as too diffuse. Some of the stakeholders have
called for the establishment of a position or NextGen program office
that reports directly to the FAA Administrator to ensure accountability
for NextGen results. These stakeholders have expressed frustration that
a program as large and important as NextGen does not follow the
industry practice of having one person with the authority to make key
decisions. They point out that although the COO is nominally in charge
of NextGen, the COO must also manage FAA's day-to-day air traffic
operations and may therefore not be able to devote enough time and
attention to managing NextGen. In addition, these stakeholders note
that many of NextGen's capabilities span FAA operational units whose
heads are on the same organizational level as the head of OEP or are
outside ATO, and they believe that an office above OEP and these
operational units is needed. In prior work, we have found that programs
can be implemented most efficiently when managers are empowered to make
critical decisions and are held accountable for results.[Footnote 26]
Another management action is needed to help ensure that FAA acquires
the skills required for implementation, such as contract management and
systems integration skills. Because of the scope and complexity of the
NextGen implementation effort, FAA may not have the in-house expertise
to manage it without assistance. In November 2006, we recommended that
FAA examine its strengths and weaknesses and determine whether it has
the technical expertise and contract management expertise that will be
needed to define, implement, and integrate the numerous complex
programs inherent in the transition to NextGen.[Footnote 27] In
response to our recommendation, FAA has contracted with the National
Academy of Public Administration (NAPA) to determine the mix of skills
and number of skilled persons, such as technical personnel and program
managers, needed to implement the new OEP and to compare those
requirements with FAA's current staff resources. In December 2007, NAPA
provided FAA with its report on the types of skills FAA will require to
implement NextGen, and it has undertaken a second part of the study
that focuses on identifying any skill gaps between FAA's current staff
and the staff that would be required to implement NextGen.[Footnote 28]
NAPA officials told us that they expect to publish the findings of the
second part of the study in the summer of 2008. We believe this is a
reasonable approach that should help FAA begin to address this
challenge as soon as possible. It may take considerable time to select,
hire, train, and integrate into the NextGen initiative what could be a
large number of staff.
We have also identified potential approaches for supplementing FAA's
capabilities, such as having FAA contract with a lead systems
integrator (LSI)-that is, a prime contractor who would help to ensure
that the discrete systems used in NextGen will operate together and
whose responsibilities may include designing system solutions,
developing requirements, and selecting major system and subsystem
contractors.[Footnote 29] However, this approach would require careful
oversight to ensure that the government's interests are protected and
could pose significant project management and oversight challenges for
the Joint Planning and Development Office (JPDO), the organization
within FAA responsible for planning NextGen, and for FAA.
Deploying Available NextGen Components Can Demonstrate Their Ability to
Operate Together and Achieve Anticipated Efficiencies:
Moving from planning to implementing some components of NextGen can
begin to demonstrate the potential of the system as well as reduce
congestion in some areas of the country, thereby also reducing
emissions. Many of the technologies and procedures planned for NextGen
are already available, and a few have been implemented individually,
such as the CDA procedures in use in Los Angeles and Louisville and ADS-
B in Alaska. However, the available technologies and procedures have
not yet been deployed simultaneously to demonstrate that they can be
operated safely as an integrated suite of technologies and procedures
in the national airspace system. Several stakeholders have suggested
that FAA consider a gradual rollout of NextGen technologies and
procedures in a particular area. For example ADS-B technologies, CDA
and RNAV/RNP procedures, and high-density airport operations could be
deployed in a defined area of the current system, possibly in sequence
over time, to test their combined use and demonstrate the safety of an
integrated suite of NextGen advancements. Such a graduated rollout is
sometimes referred to as "NextGen Lite." FAA is currently considering a
demonstration project in Florida and Georgia, in which it, together
with aviation equipment manufacturers and municipalities, would use the
NextGen capabilities of ADS-B, RNAV, and RNP for on-demand air taxi
fleet[Footnote 30] operations. As other NextGen capabilities, such as
System-Wide Information Management (SWIM),[Footnote 31] are deployed
and as air taxi fleet operations move to other airports and regions,
the demonstration will be expanded to include those new capabilities
and other airports and regions. According to the airlines and other
stakeholders we interviewed, a demonstration of the successful
integration of NextGen capabilities and of efficiencies resulting from
their use would give the airlines an incentive to equip their aircraft
with NextGen technologies. They could then lower their costs by
reducing their fuel consumption and decrease the impact of their
operations on the environment. The findings from our research indicate
that such regional or targeted demonstrations could accelerate the
delivery of NextGen benefits while helping to ensure safe operations
within the current system. In addition, demonstrations can increase
stakeholders' confidence in the overall NextGen initiative.
Resolving Aeronautics R&D Funding Issues Is a Further Step in
Addressing Aviation Emissions:
Federal funding for aeronautics research, the category that includes
work on aviation emissions, has declined over the past decade,
particularly for NASA, which historically provided most of the funding
for this type of research. NASA's current aeronautics research budget
is about half of what it was in the mid-1990s. Moreover, the budget
request for aeronautics R&D for fiscal year 2009 is $447 million, or
about 25 percent less than the $594 million provided in fiscal year
2007. (See table 1.) According to NASA, about $280 million of the
proposed $447 million would contribute to NextGen. In addition,
according to NASA officials, a significant portion of the funding for
subsonic fixed-wing aircraft is directed toward emissions-related
research, and many other research efforts contribute directly or
indirectly to potential emissions-reduction technologies.
Table 1: The President's Budget for NASA's Aeronautics Programs for
Fiscal Years 2007 and 2008 and Budget Projections for Fiscal Years 2009
through 2013 (Dollars in millions):
Program: Aviation Safety: Integrated Vehicle Health Management;
Enacted: FY 2007: 30.7;
Enacted: FY 2008: 222.2;
Requested: FY 2009: 19.7;
Proposed: FY 2010: 19.9;
Proposed: FY 2011: 18.8;
Proposed: FY 2012: 18.6;
Proposed: FY 2013: 19.2.
Program: Aviation Safety: Aging Aircraft;
Enacted: FY 2007: 14.9;
Enacted: FY 2008: 10.0;
Requested: FY 2009: 10.6;
Proposed: FY 2010: 11.3;
Proposed: FY 2011: 11.2;
Proposed: FY 2012: 12.0;
Proposed: FY 2013: 12.4.
Program: Aviation Safety: Integrated Resilient Aircraft Control;
Enacted: FY 2007: 22.2;
Enacted: FY 2008: 15.3;
Requested: FY 2009: 17.1;
Proposed: FY 2010: 18.5;
Proposed: FY 2011: 19.0;
Proposed: FY 2012: 18.2;
Proposed: FY 2013: 18.8.
Program: Aviation Safety: Integrated Intelligent Flight Deck
Technologies;
Enacted: FY 2007: 19.5;
Enacted: FY 2008: 19.3;
Requested: FY 2009: 15.2;
Proposed: FY 2010: 16.3;
Proposed: FY 2011: 16.0;
Proposed: FY 2012: 15.7;
Proposed: FY 2013: 16.1.
Program: Aviation Safety: Subtotal;
Enacted: FY 2007: 87.3;
Enacted: FY 2008: 66.5;
Requested: FY 2009: 62.6;
Proposed: FY 2010: 65.9;
Proposed: FY 2011: 65.0;
Proposed: FY 2012: 64.5;
Proposed: FY 2013: 66.5.
Program: Airspace Systems: NextGen - Airspace;
Enacted: FY 2007: 85.1;
Enacted: FY 2008: 83.3;
Requested: FY 2009: 61.3;
Proposed: FY 2010: 56.0;
Proposed: FY 2011: 57.3;
Proposed: FY 2012: 58.5;
Proposed: FY 2013: 60.8.
Program: Airspace Systems: NextGen - Airportal;
Enacted: FY 2007: 17.4;
Enacted: FY 2008: 16.8;
Requested: FY 2009: 13.3;
Proposed: FY 2010: 16.7;
Proposed: FY 2011: 16.9;
Proposed: FY 2012: 16.9;
Proposed: FY 2013: 17.5.
Program: Airspace Systems: Subtotal;
Enacted: FY 2007: 102.5;
Enacted: FY 2008: 100.1;
Requested: FY 2009: 74.6;
Proposed: FY 2010: 72.7;
Proposed: FY 2011: 74.2;
Proposed: FY 2012: 75.4;
Proposed: FY 2013:78.4.
Program: Fundamental Aeronautics: Subsonic - Rotary Wing;
Enacted: FY 2007: 36.1;
Enacted: FY 2008: 30.8;
Requested: FY 2009: 25.8;
Proposed: FY 2010: 26.6;
Proposed: FY 2011: 26.7;
Proposed: FY 2012: 26.9;
Proposed: FY 2013: 28.0.
Program: Fundamental Aeronautics: Subsonic - Fixed Wing;
Enacted: FY 2007: 133.9;
Enacted: FY 2008: 119.9;
Requested: FY 2009: 108.4;
Proposed: FY 2010: 105.3;
Proposed: FY 2011: 107.6;
Proposed: FY 2012: 109.1;
Proposed: FY 2013: 111.5.
Program: Fundamental Aeronautics: Supersonics;
Enacted: FY 2007: 67.7;
Enacted: FY 2008: 53.0;
Requested: FY 2009: 44.0;
Proposed: FY 2010: 44.9;
Proposed: FY 2011: 44.3;
Proposed: FY 2012: 45.2;
Proposed: FY 2013: 46.6.
Program: Fundamental Aeronautics: Hypersonics;
Enacted: FY 2007: 92.8;
Enacted: FY 2008: 66.2;
Requested: FY 2009: 57.3;
Proposed: FY 2010: 56.4;
Proposed: FY 2011: 56.5;
Proposed: FY 2012: 57.4;
Proposed: FY 2013: 58.4.
Program: Fundamental Aeronautics: Subtotal;
Enacted: FY 2007: 330.4;
Enacted: FY 2008: 269.9;
Requested: FY 2009: 235.4;
Proposed: FY 2010: 233.2;
Proposed: FY 2011: 235.2;
Proposed: FY 2012: 238.6;
Proposed: FY 2013: 244.6.
Program: Aeronautics Test Program: Aero Ground Test Facilities;
Enacted: FY 2007: 48.5;
Enacted: FY 2008: 50.0;
Requested: FY 2009: 48.2;
Proposed: FY 2010: 49.4;
Proposed: FY 2011: 50.8;
Proposed: FY 2012: 51.0;
Proposed: FY 2013: 51.0.
Program: Aeronautics Test Program: Flight Operations and Test
Infrastructure;
Enacted: FY 2007: 25.0;
Enacted: FY 2008: 25.1;
Requested: FY 2009: 25.6;
Proposed: FY 2010: 26.4;
Proposed: FY 2011: 27.2;
Proposed: FY 2012: 27.2;
Proposed: FY 2013: 27.2.
Program: Aeronautics Test Program: Subtotal;
Enacted: FY 2007: 73.5;
Enacted: FY 2008: 75.1;
Requested: FY 2009: 73.9;
Proposed: FY 2010: 75.8;
Proposed: FY 2011: 78.0;
Proposed: FY 2012: 78.2;
Proposed: FY 2013: 78.2.
Program: Total;
Enacted: FY 2007: 593.8;
Enacted: FY 2008: 511.7;
Requested: FY 2009: 446.5;
Proposed: FY 2010: 447.5;
Proposed: FY 2011: 452.4;
Proposed: FY 2012: 456.7;
Proposed: FY 2013: 467.7.
Source: NASA.
Note: Most of the research on aircraft emissions reductions that NASA
performs is funded through the Fundamental Aeronautics - Fixed Wing
program.
[End of table]
As its funding for aeronautics R&D has declined, NASA has emphasized
fundamental research, which serves as the basis for developing
technologies and tools that can later be integrated into aviation
systems, and has focused less on developmental and demonstration work.
As a result, NASA is now sometimes developing technologies to a lower
maturity level than in the past, and the technologies are less ready
for manufacturers to adopt them, resulting in a gap in the research
needed to bring technologies to a level where they can be transferred
to industry for further development. Failure to address this gap could
postpone the development of emissions-reduction technologies.
As a partial response to the gap, the administration has proposed some
additional funding for FAA that could be used to further develop NASA's
and others' emissions-and noise reduction technologies. Specifically,
FAA's reauthorization proposal seeks $111 million through fiscal year
2011 for the CLEEN Engine and Airframe Technology Partnership,[Footnote
32] which FAA officials said is intended to provide for earlier
maturation of emissions and noise technologies while NASA focuses on
longer-term fundamental research on noise and emissions. The CLEEN
partnership, which is also contained in the House's FAA reauthorization
bill,[Footnote 33] would create a program for the development and
maturation of certifiable engine and airframe technologies for aircraft
over the next 10 years which would reduce aviation noise and emissions.
The legislation would require the FAA Administrator, in coordination
with the NASA Administrator, to establish objectives for developing
aircraft technology outlined in the legislation. The technology
requested to be developed would increase aircraft fuel efficiency
enough to reduce greenhouse gas emissions by 25 percent relative to
1997 subsonic jet aircraft technology, and, without increasing other
gaseous or particle emissions, reduce takeoff-cycle nitrogen oxide
emissions by 50 percent relative to ICAO's standard. Although FAA's
reauthorization bill has not yet been enacted, the administration's
proposed fiscal year 2009 budget includes $10 million for the CLEEN
program.
The CLEEN program would be a first step toward further maturing
emissions and noise reduction technologies, but experts agree that the
proposed funding is insufficient to achieve needed emissions
reductions. While acknowledging that CLEEN would help bridge the gap
between NASA's R&D and manufacturers' eventual incorporation of
technologies into aircraft designs, aeronautics industry
representatives and experts we consulted said that the program's
funding levels may not be sufficient to attain the goals specified in
the proposal. According to these experts, the proposed funding levels
would allow for the further development of one or possibly two
projects. Moreover, in one expert's view, the funding for these
projects may be sufficient only to develop the technology to the level
that achieves an emissions-reduction goal in testing, not to the level
required for the technology to be incorporated into a new engine
design. Nevertheless, according to FAA and some experts we consulted,
the CLEEN program amounts to a pilot project, and if it results in the
development of emissions-reduction technologies that can be introduced
into aircraft in the near future, it could lead to additional funding
from the government or industry for such efforts.
FAA and NASA have identified the R&D that is needed for NextGen, but
have not determined what needs to be done first, at what cost, to
demonstrate and integrate NextGen technologies into the national
airspace system. Completing this prioritization is critical to avoid
spending limited funds on lower-priority efforts or conducting work out
of sequence. Once the identified R&D has been prioritized and
scheduled, cost estimates can be developed and funds budgeted.
Prioritizing research needs is an essential step in identifying the
resources required to undertake the research.
The European Union is investing substantially in R&D that can lead to
fuel-efficient, environmentally friendly aircraft. In February 2008,
the European Union announced the launch of the Clean Sky Joint
Technology Initiative, with total funding of $2.4 billion over 7 years-
-the European Union's largest-ever research program. The initiative
establishes a Europe-wide partnership between industry, universities,
and research centers and aims to reduce aircraft emissions of carbon
dioxide and nitrogen oxides by up to 40 percent and aircraft noise
levels by 20 decibels. According to FAA, it is difficult to compare
funding levels for U.S. and European R&D efforts because of differences
in program structures and funding mechanisms, Nevertheless, foreign
government investments of such magnitude in R &D on environmentally
beneficial technologies could reduce the competitiveness of the U.S.
aircraft manufacturing industry, since greater investments are likely
to lead to greater improvements in fuel efficiency and keep U.S.
aircraft manufacturers competitive in the global economy as well as
reducing aviation's impact on the environment.
Reducing the Impact of Aviation Emissions Poses Technical, Financial,
and Regulatory Challenges:
Reducing aviation emissions will require technological advances, the
integration of lower-emitting aircraft and NextGen technologies into
airline fleets, and strengthened or possibly new regulations to improve
air quality and limit greenhouse gas emissions. Fulfilling these
requirements will pose challenges to aviation because of the technical
difficulties involved in developing technologies that can
simultaneously address air pollutants, greenhouse gases, and noise;
constraints on the airline industry's resources to invest in new
aircraft and technologies needed to reduce emissions and remain
competitive; and the impact that emissions regulations can have on the
aviation system's expansion and the financial health of the aviation
industry.
Simultaneously Addressing Air Pollutants, Greenhouse Gases, and Noise
from Aircraft Presents Technical Challenges:
Although the aviation industry has made strides in lowering emissions,
more reductions are needed to keep pace with the projected growth in
aviation, and achieving these reductions will be technically
challenging. NASA's efforts to improve jet engine designs illustrate
this challenge: While new designs have increased fuel efficiency,
reduced most emissions, and lowered noise, they have not achieved
comparable reductions in nitrogen oxide emissions. Nitrogen oxide
emissions have increased because new aircraft engines operate at higher
temperatures, producing more power with less fuel and lower carbon
dioxide and carbon monoxide emissions, but also producing higher
nitrogen oxide emissions, particularly during landings and takeoffs,
when engine power settings are at their highest. It is during the
landing/takeoff cycle that nitrogen oxide emissions also have the
greatest impact on air quality. As discussed, nitrogen oxides
contribute to ground-level ozone formation. Similarly, as we noted in a
report on NASA's and FAA's aviation noise research earlier this
year,[Footnote 34] it is technologically challenging to design aircraft
engines that simultaneously produce less noise and fewer greenhouse gas
and other emissions. Although it is possible to design such engines,
the reductions in greenhouse gases could be limited in engines that
produce substantially less noise. NASA and industry are working on
technologies to address these environmental trade-offs. For example,
the Pratt & Whitney geared turbo fan engine that we mentioned earlier
is expected to cut nitrogen oxide emissions in half while also
improving fuel efficiency and thereby lowering carbon dioxide
emissions. Nevertheless, it remains technologically challenging to
design aircraft that can reduce one environmental concern without
increasing another.
In a 2004 report to Congress on aviation and the environment,[Footnote
35] FAA noted that the interdependencies between various policy,
technological, and operational options for addressing the environmental
impacts of aviation and the full economic consequences of these options
had not been appropriately assessed. However, in recent years, FAA has
made progress in this area, including its sponsorship of the previously
mentioned PARTNER study on the interrelationships between noise and
emissions. This study can be used to assess the costs and benefits of
aviation environmental policy options.
The Financial Condition of the Airline Industry Creates a Challenge to
Implementing Emissions-Reduction Technologies:
Most U.S. airlines have stated that they plan to invest in aircraft and
technologies that can increase fuel efficiency and lower emissions, but
in the near term, integrating new aircraft into the fleet, or
retrofitting aircraft with technologies that can improve their
operational efficiency, poses financial challenges to the airline
industry. Aircraft have an average lifespan of about 30 years, and the
airlines can take almost that entire period to pay for an aircraft. The
current fleet is, on average, about half as many years old--11 years
for wide-body aircraft, and 14 years for narrow-body aircraft--and
therefore is expected to be in operation for many years to come. In
addition, the financial pressures facing many airlines make it
difficult for them to upgrade their fleets with new, state-of-the-art
aircraft, such as the Boeing 787 and Airbus A380, which are quieter and
more fuel efficient, emitting lower levels of greenhouse gases.
[Footnote 36] Currently, U.S. carriers have placed a small proportion
(40, or less than 6 percent) of the over 700 orders that Boeing
officials say the company has received for its 787 model. Furthermore,
no U.S. carriers have placed orders for the new Airbus 380. These
financial pressures also limit the airlines' ability to equip new and
existing aircraft with NextGen technologies such as ADS-B that can
enable more efficient approaches and descents, resulting in lower
emissions levels. FAA estimates that it will cost the industry about
$14 billion to equip aircraft to take full advantage of NextGen.
Delays by airlines in introducing more fuel-efficient, lower-emitting
aircraft into the U.S. fleet and in equipping or retrofitting the fleet
with the technologies necessary to operate NextGen could limit FAA's
ability to efficiently manage the forecasted growth in air traffic.
Without significant reductions in emissions and noise around the
nation's airports, efforts to expand their capacity could be stalled
and the implementation of NextGen delayed because of concerns about the
impact of aviation emissions. As we previously reported,[Footnote 37]
offering operational advantages, such as preferred takeoff and landing
slots, to fuel-efficient, lower-emitting aircraft or aircraft equipped
with ADS-B could create incentives for the airlines to invest in the
necessary technologies. Similarly, as noted, deploying an integrated
suite of NextGen technologies and procedures in a particular region
could create incentives for carriers to equip their aircraft with
NextGen technologies.
More Stringent Regulatory Standards Pose Challenges for Airport
Expansion Projects:
Concerns about the health effects of air pollutants have led to more
stringent air quality standards that could increase the costs or delay
the implementation of airport expansion projects. In recent years, EPA
has been implementing a more stringent standard for ozone emissions to
better protect the health of people exposed to it, and this standard
could require more airports to tighten controls on nitrogen oxides and
some types of volatile organic compounds that also contribute to ozone
formation. Under the current standard,[Footnote 38] 122 airports are
located in areas that are designated as nonattainment areas. This
number includes 43 of the 50 busiest U.S. commercial service airports.
In March 2008, EPA further revised the ozone standard, because new
evidence demonstrated that exposure to ozone at levels below the level
of the current standard are associated with a broad array of adverse
health effects.[Footnote 39] This recent revision to the ozone standard
will increase the number of U.S. counties, and hence airports, that
will be in nonattainment. EPA estimated that the number of affected
counties could potentially grow from 104 to 345 nationwide. While the
exact number of airports that will be affected has not been officially
determined at this time, FAA estimates that a modest number of
commercial service airports in California, Arizona, Utah, Texas,
Oklahoma, Arkansas, and along the gulf coast to Florida will be in
nonattainment areas for the revised 8-hour ozone standard. According to
EPA, any development project beginning in 2011 at these airports would
have to conform to the state implementation plan.
As communities gain more awareness of the health and environmental
effects of aviation emissions, opposition to airport expansion
projects, which has thus far focused primarily on aviation noise, could
broaden to include emissions. According to a California air quality
official, many of the same communities that have interacted with
airports over aviation noise have more recently recognized that they
could also be affected by emissions from airport sources. In Europe,
concerns about the impact of aviation on air quality and climate change
have led to public demands for tighter control over aircraft emissions,
and these demands have hindered efforts to expand airports in
Birmingham, and London (Heathrow). Moreover, a plan to expand London's
Stansted Airport was rejected because of concerns about climate change
that could result from additional emissions.
To minimize constraints on the future expansion of airport capacity
stemming from concerns about the health and environmental effects of
aviation emissions, it will be important for airports; the federal and
state governments; and the airline industry to work together to
accurately characterize and address these concerns and to take early
action to mitigate emissions. As noted, constraints on efforts to
expand airports or aviation operations could affect the future of
aviation because the national airspace system cannot expand as planned
without a significant increase in airport capacity. The doubling or
tripling of air traffic that FAA expects in the coming decades cannot
occur without additional airports and runways.
Market-Based Initiatives to Reduce Aviation Emissions of Greenhouse
Gases Could Pose Challenges for U.S. Airlines by Increasing Their
Costs:
Concerns about the environmental effects of greenhouse gas emissions
have grown steadily over the years, leading to national and
international efforts to limit them. In the:
In the United States, EPA has not regulated greenhouse gas emissions;
[Footnote 40] however, Congress is taking steps to deal with climate
change, some of which could include market-based measures that would
affect the aviation industry. For example, several bills were
introduced in the 110th Congress to initiate cap and trade[Footnote 41]
programs for greenhouse gas emissions[Footnote 42] None of these bills
would include aviation directly in a cap and trade program. However,
some could have indirect consequences for the aviation industry by, for
example, requiring fuel producers to purchase allowances through the
system to cover the greenhouse gas content of the fuel they sell to the
aviation sector. The cost of purchasing these allowances could be
passed on to fuel consumers, including airlines, raising the cost of
jet fuel. Fuel is already the airline industry's largest cost.
According to the Air Transport Association, cap and trade programs that
significantly increase airline fuel costs could have significant
consequences for the industry and such programs could make it more
difficult for carriers to pay for aircraft or technologies that would
reduce greenhouse gas emissions. As we have previously noted,[Footnote
43] cap and trade programs can cost-effectively reduce emissions of
greenhouse gases such as carbon dioxide, especially when compared with
other regulatory programs. However, it is important that the impact of
such measures on various sectors of the economy, such as the aviation
industry, be thoroughly considered.
Internationally, ICAO has not set standards for aircraft carbon dioxide
emissions,[Footnote 44] but it has been working, with the support of
FAA, other government aviation authorities, and the aviation industry,
to develop a strategy for addressing the impact of aviation on climate
change, among several efforts to address climate change. For example,
ICAO published a manual for countries, Operational Opportunities to
Minimize Fuel Use and Reduce Emissions. In 2004, ICAO endorsed the
development of an open emissions trading system as one option countries
might use and endorsed draft guidance for member states on establishing
the structural and legal basis for aviation's participation in a
voluntary open trading system. The guidance includes information on key
elements of a trading system, such as reporting, monitoring, and
compliance, while encouraging flexibility to the maximum extent
possible. In adopting the guidance last fall at the ICAO Assembly, all
190 Contracting States--with the exception of those in the European
Union--agreed that the inclusion of one country's airlines in another
country's emissions trading system should be based on mutual consent
between governments.
Consistent with the requirement to pursue reductions of greenhouse gas
emissions from international aviation through ICAO, some countries that
have included the aviation sector in their emissions trading systems or
other emissions-reduction efforts have, excluded international flights.
Consequently, these countries' efforts will not affect U.S. airlines
that fly into their airports. The European Union (EU), however, is
developing legislation, which has not been finalized, that would
include both domestic and international aviation in an emissions
trading scheme.[Footnote 45] As proposed, the EU's scheme would apply
to air carriers flying within the EU and to carriers, including U.S.
carriers, flying into and out of EU airports in 2012. For example,
under the EU proposal, a U.S. airline's emissions in domestic airspace
as well as over the high seas would require permits if a flight landed
or departed from an EU airport. Airlines whose aircraft emit carbon
dioxide at levels exceeding prescribed allowances would be required to
reduce their emissions or to purchase additional allowances. Although
the legislation seeks to include U.S. airlines within the emissions
trading scheme, FAA and industry stakeholders have argued that U.S.
carriers would not legally be subject to the legislation.
While the EU's proposal to include international aviation in its
emissions trading system is intended to help forestall the potential
catastrophic effects of climate change, according to FAA and airlines,
it will also affect the aviation industry's financial health. In
particular, according to FAA and airline and aircraft and engine
manufacturing industry representatives, the EU's proposal could
disadvantage U.S. airlines, which have older, less fuel-efficient
fleets than their European competitors. Paying for emissions credits
could, according to U.S. airlines, also leave them with less money for
other purposes, including investing in newer, more fuel-efficient
aircraft and technologies to improve flight efficiency and reduce fuel
usage. Furthermore, according to U.S. carriers, the proposed trading
scheme unfairly penalizes the aviation sector because it lacks a
readily available non-carbon-based alternative fuel, whereas other
sectors can use alternative fuels to reduce their emissions.
The governments of many nations, including the United States, oppose
the European Union's proposal to unilaterally include international
aviation in its emissions trading system because the proposed approach
is not consistent with ICAO guidance. Furthermore, such an approach
could be inconsistent with international aviation agreements and may
not be enforceable. According to FAA, the EU's inclusion of aviation in
its emissions trading scheme violates the Chicago Convention on
International Civil Aviation[Footnote 46] and other international
agreements. FAA further notes that the EU proposal ignores differences
in the U.S. and EU aviation systems[Footnote 47] and ignores a
performance-based approach in which countries decide which measures are
most appropriate for goals on emissions. We are currently undertaking
for this Subcommittee a study of the EU emissions trading system and
its potential impact on U.S. airlines, and other issues relating to
aviation and climate change.[Footnote 48]
Mr. Chairman, this concludes my prepared statement. I would be pleased
to respond to any questions that you or other Members of the
Subcommittee may have.
Contacts and Acknowledgments:
For further information on this testimony, please contact Dr. Gerald L.
Dillingham at (202) 512-2834 or by email at dillinghamg@gao.gov.
Individuals making key contributions to this testimony include Ed
Laughlin, Lauren Calhoun, Bess Eisenstadt, Jim Geibel, Rosa Leung, Josh
Ormond, Richard Scott, and Larry Thomas.
[End of section]
Appendix I: Federal Agency Views on Health and Environmental Effects of
Air Pollution:
Pollutant: Ozone;
Heath effects: Lung function impairment, effects on exercise
performance, increased airway responsiveness, increased susceptibility
to respiratory infection, increased hospital admissions and emergency
room visits, pulmonary inflammation, and lung structure damage (long
term);
Environmental effects: Results from animal studies indicate that
repeated exposure to high levels of ozone for several months or more
can produce permanent structural damage in the lungs. Ozone is also
responsible for several billion dollars of agricultural crop yield loss
in the United States each year.
Pollutant: Carbon monoxide;
Heath effects: Most serious for those who suffer from cardiovascular
disease. Healthy individuals are also affected, but only at higher
levels of exposure. Exposure to elevated carbon monoxide levels is
associated with visual impairment, reduced work capacity, reduced
manual dexterity, poor learning ability, and difficulty in performing
complex tasks;
Environmental effects: Adverse health effects on animals similar to
effects on humans.
Pollutant: Nitrogen oxides;
Heath effects: Lung irritation and lower resistance to respiratory
infections;
Environmental effects: Acid rain, visibility degradation, particle
formation. Contributes toward ozone formation, and acts as a greenhouse
gas in the atmosphere and, therefore, may contribute to climate change.
Pollutant: Particulate matter;
Heath effects: Effects on breathing and respiratory systems, damage to
lung tissue, cancer, and premature death. The elderly, children, and
people with chronic lung disease, influenza, or asthma, tend to be
especially sensitive to the effects of particulate matter;
Environmental effects: Visibility degradation, damage to monuments and
buildings, safety concerns for aircraft from reduced visibility.
Pollutant: Volatile organic compounds;
Heath effects: Eye and respiratory tract irritation, headaches,
dizziness, visual disorders, and memory impairment;
Environmental effects: Contribute to ozone formation, odors, and have
some damaging effect on buildings and plants.
Pollutant: Carbon dioxide, water vapor, and contrails;
Heath effects: None;
Environmental effects: Act as greenhouse gases in the atmosphere and,
therefore, may contribute to climate change. Contrails and contrail-
induced clouds produce warming effect regionally where aircraft fly.
Pollutant: Sulfur dioxide;
Heath effects: Breathing, respiratory illness, alterations in pulmonary
defenses, and aggravation of existing cardiovascular disease;
Environmental effects: Together, sulfur dioxide and nitrogen oxides are
the major precursors to acid rain, which is associated with the
acidification of lakes and streams, accelerated corrosion of buildings
and monuments, and reduced visibility.
Sources: EPA and FAA.
[End of table]
[End of section]
Appendix II: Examples of the National Aeronautics and Space
Administration's Research and Development Programs Supporting NextGen:
NextGen research and development (R&D) needs:
* Safety management procedures that can predict, rather than respond
to, safety risks, in a high density, complex operating environment;
research to support safety analysis, development of advanced materials
for continued airworthiness of aircraft, aircraft system and equipage
management; and adaptive aircraft control systems to allow the crew and
aircraft to recover from unsafe conditions;
NextGen capabilities from the National Aeronautics and Space
Administration's (NASA) R&D programs:
* Under its Aviation Safety program, NASA research supports development
of Safety Management Systems to provide a systematic approach to manage
safety risks; integrates prediction and mitigation of risks prior to
aircraft accidents or incidents; and shares safety-related information
through programs such as the Aviation Safety Analysis and Information
Sharing program.
NextGen research and development (R&D) needs:
* Improved air traffic management technologies to manage airspace
configuration, support increases in volume and complexity of traffic
demands, mitigate weather impacts, and maintain safe and efficient
operations at airports, decrease runway incursions, and address wake
vortex issues;
NextGen capabilities from the National Aeronautics and Space
Administration's (NASA) R&D programs:
* Under its Airspace Systems program, NASA research supports
development of variable separation standards based on aircraft
performance levels in the en route environment; trajectory-based
operations, traffic spacing, merging, metering, flexible terminal
airspace, and expanded airport access; technologies and procedures for
safe runway procedures in low-visibility conditions; coordinated
arrival/departure management; and mitigation of weather and wake vortex
issues.
NextGen research and development (R&D) needs:
* Management of aviation growth to meet the complexity of operations
within the NextGen environment, regulation and certification of new
manned and unmanned aircraft, and management of operations in an
environmentally sound manner;
NextGen capabilities from the National Aeronautics and Space
Administration's (NASA) R&D programs:
* Under its Fundamental Aeronautics program, NASA research supports
development of improved performance for the next generation of
conventional subsonic aircraft, rotorcraft and supersonic aircraft and
develops methods for environmental management system to measure and
assess reductions in air quality impact, noise, and emissions.
Source: GAO analysis of Joint Planning and Development Office and NASA
information.
[End of table]
[End of section]
Related GAO Products:
Aviation and the Environment: FAA's and NASA's Research and Development
Plans for Noise Reduction Are Aligned, but the Prospects of Achieving
Noise Reduction Goals Are Uncertain. [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO-08-384]. Washington, D.C.: February 15, 2008.
Aviation and the Environment: Impact of Aviation Noise on Communities
Presents Challenges for Airport Operations and Future Growth of the
National Airspace System. [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO-08-216T]. Washington, D.C.: October 24, 2007.
Climate Change: Agencies Should Develop Guidance for Addressing the
Effects on Federal Land and Water Resources. [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-07-863]. Washington, D.C.: August
7, 2007.
Responses to Questions for the Record; Hearing on the Future of Air
Traffic Control Modernization. [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO-07-928R]. Washington, D.C.: May 30, 2007.
Responses to Questions for the Record; Hearing on JPDO and the Next
Generation Air Transportation System: Status and Issues. [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-07-918R]. Washington, D.C.: May
29, 2007.
Next Generation Air Transportation System: Status of the Transition to
the Future Air Traffic Control System. [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-07-748T]. Washington, D.C.: May
9, 2007.
Joint Planning and Development Office: Progress and Key Issues in
Planning the Transition to the Next Generation Air Transportation
System. [hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-07-693T].
Washington, D.C.: March 29, 2007.
Next Generation Air Transportation System: Progress and Challenges in
Planning and Implementing the Transformation of the National Airspace
System. [hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-07-649T].
Washington, D.C.: March 22, 2007.
Next Generation Air Transportation System: Progress and Challenges
Associated with the Transformation of the National Airspace System.
[hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-07-25]. Washington,
D.C.: November 13, 2006.
Aviation and the Environment: Strategic Framework Needed to Address
Challenges Posed by Aircraft Emissions. [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-03-252]. Washington, D.C.:
February 28, 2003.
Aviation and the Environment: Transition to Quieter Aircraft Occurred
as Planned, but Concerns about Noise Persist. [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-01-1053]. Washington, D.C.:
September 28, 2001.
Aviation and the Environment: Aviation's Effects on the Global
Atmosphere Are Potentially Significant and Expected to Grow.
[hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO/RCED-00-57].
Washington, D.C.: February 18, 2000.
Aviation and the Environment: Results from a Survey of the Nation's 50
Busiest Airports. [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO/RCED-00-222]. Washington, D.C.: August 30, 2000.
Aviation and the Environment: Airport Operations and Future Growth
Present Environmental Challenges. [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO/RCED-00-153]. Washington, D.C.: August 30, 2000.
[End of section]
Footnotes:
[1] These emissions include airborne pollutants, which affect air
quality, and greenhouse gases, primarily carbon dioxide, which are
produced by the combustion of fossil fuel, and contribute to climate
change.
[2] These figures are based on a long-range FAA forecast using 2006 as
the baseline.
[3] See the list of related products at the end of this statement,
especially GAO, Next Generation Air Transportation System: Progress and
Challenges in Planning and Implementing the Transformation of the
National Airspace System, [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO-07-649T] (Washington, D.C.: Mar. 22, 2007.)
[4] As we noted in our recent testimony before this Subcommittee,
aviation noise has been a greater constraint on airport expansion
efforts than aviation emissions, but we are limiting our discussion in
this testimony to aviation emissions.
[5] 42 U.S.C. §4332(2)(C).
[6] States are required to submit implementation plans to EPA for
reducing emissions in areas that fail to meet the National Ambient Air
Quality Standards set by EPA under the Clean Air Act for common air
pollutants with health and environmental effects (known as criteria
pollutants). Geographic areas that have levels of a criteria pollutant
above those allowed by the standard are called nonattainment areas.
[7] 42 U.S.C. §7506(c)(1) (The Conformity Provision).
[8] ICAO is an organization affiliated with the United Nations that
aims to promote the establishment of international civilian aviation
standards and recommended practices and procedures. FAA, as the U.S.
representative to ICAO, in consultation with EPA, works with
representatives from other countries to formulate aircraft emissions
standards.
[9] See the list of related GAO products at the end of this statement,
especially GAO, Aviation and the Environment: Strategic Framework
Needed to Address Challenges Posed by Aircraft Emissions, [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-03-252] (Washington, D.C.; Feb.
28, 2003).
[10] We are currently undertaking a study on aviation environmental
trends, efforts, and challenges for this Subcommittee and the
Subcommittee on Space and Aeronautics, Committee on Science and
Technology, House of Representatives.
[11] Motor vehicles include cars and buses for airport operations and
passenger, employee, and rental agency vehicles.
[12] Ground service equipment includes aircraft tugs, baggage and belt
loaders, generators, lawn mowers, snow plows, loaders, tractors, air-
conditioning units, and cargo moving equipment.
[13] Hazardous air pollutants from aviation activities include benzene
and formaldehyde.
[14] Ground-level ozone is formed when nitrogen oxides and volatile
organic compounds as well as other gases and substances are mixed and
heated in the atmosphere.
[15] Contrails are clouds and condensation trails that form when water
vapor condenses and freezes around small particles (aerosols) in
aircraft exhaust.
[16] Intergovernmental Panel on Climate Change, Aviation and the Global
Atmosphere (1999).
[17] Intergovernmental Panel on Climate Change, Fourth Assessment
Report, Summary for Policy Makers, Cambridge University Press,
Cambridge, UK, November 2007.
[18] A critical component of RNP is the ability of the navigation
system to monitor its achieved navigation performance and to identify
for the pilot if an operational requirement is or is not being met
during an operation.
[19] [hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-03-252].
[20] Alternatively, some scientists studying options for addressing
climate change believe that a price on emissions would represent the
most effective means of achieving reductions overall.
[21] FAA Centers of Excellence are FAA partnerships with universities
and affiliated industry associations and businesses throughout the
country that conduct aviation research in a number of areas, including
advanced materials, aircraft noise, and aircraft emissions. PARTNER is
a cooperative research organization that includes 10 collaborating
universities and approximately 50 advisory board members who represent
aerospace manufacturers, airlines, airports, state and local
governments, and professional and community groups. NASA, FAA, and
Transport Canada are sponsors of PARTNER. The collaborating
universities and organizations represented on the advisory board
provide equal matches for federal funds for research and other
activities.
[22] ACRP was authorized in 2003 as part of Vision 100--Century of
Aviation Reauthorization Act, Pub. L. 108-176, Section 712 (Dec 12,
2003).
[23] CAAFI, established in October 2006, is sponsored by the Air
Transport Association, the Aerospace Industries Association, and the
Airports Council International-North America under the direction of
FAA, and involves stakeholders from industry, universities, and other
federal agencies, including NASA.
[24] This goal is at a pressure ratio of 30, over the ICAO standard
adopted at the Committee on Aviation Environmental Protectionís sixth
meeting (CAEP 6), with commensurate reductions over the full pressure
ratio range.
[25] "N" refers to the current generation of tube-and-wing aircraft
entering service in 2008, such as the Boeing 787.
[26] See GAO, Best Practices: Better Support of Weapon System Program
Managers Needed to Improve Outcomes, [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO-06-110] (Washington, D.C.: Nov. 30, 2005). In this study
of private-sector best practices that could be applied to federal
programs, we found that program managers at highly successful companies
were empowered to decide whether programs were ready to move forward
and to resolve problems and implement solutions. In addition, program
managers were held accountable for their choices.
[27] GAO, Next Generation Air Transportation System: Progress and
Challenges Associated with the Transformation of the National Airspace
System, [hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-07-25]
(Washington, D.C.: Nov. 13, 2006).
[28] NAPA, Workforce Needs Analysis for the Next Generation Air
Transportation System (NEXTGEN): Preliminary Findings and Observations
(Washington, D.C.: December 2007).
[29] [hyperlink, http://www.gao.gov/cgi-bin/getrpt?GAO-07-25].
[30] Air taxis are small aircraft that can be hired to carry passengers
or cargo and are regulated under Part 135 of the Federal Aviation
Regulations.
[31] SWIM is information-management architecture for the national
airspace system, acting as its "World-Wide Web." SWIM will manage
surveillance, weather, and flight data, as well as aeronautical and
system status information and will provide the information securely to
users.
[32] CLEEN stands for continuous lower energy emissions and noise.
[33] H.R. 2881.
[34] GAO, Aviation and the Environment: Impact of Aviation Noise on
Communities Presents Challenges for Airport Operations and Future
Growth of the National Airspace System, [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-08-216T] (Washington, D.C.: Oct.
24, 2007).
[35] FAA, Aviation and the Environment: A National Vision Statement,
Framework for Goals and Recommended Actions (Washington, D.C.: December
2004).
[36] We are currently undertaking a study for this Subcommittee and the
House Committee on Transportation and Infrastructure that, among other
things, will assess the financial condition of the airlines.
[37] GAO, Aviation and the Environment: FAA'S and NASA's Research and
Development Plan's for Noise Reduction Are Aligned, but the Prospects
of Achieving Noise Reduction Goals Are Uncertain, [hyperlink,
http://www.gao.gov/cgi-bin/getrpt?GAO-08-384] (Washington, D.C.: Feb.
15, 2008).
[38] In 2003, EPA began implementing a new standard that called for
concentrations of ozone not to exceed 0.08 parts per million over an 8-
hour period. The former standard required concentrations not to exceed
0.12 parts per million over a 1-hour period. The more stringent
standard resulted in the designation of more nonattainment areas for
ozone. These areas contained 12 airports.
[39] 73 Fed. Reg. 16436 (Mar. 27, 2008). The new standard would lower
the allowed concentrations of ozone from 0.08 parts per million in an 8-
hour period to 0.075 parts per million during that period.
[40] Recently, however, the Supreme Court ruled that greenhouse gases
meet the Clean Air Act's definition of an air pollutant and that EPA
has the statutory authority to regulate greenhouse gas emissions from
new motor vehicles under the Clean Air Act. Massachusetts v.
Environmental Protection Agency, 127 S.Ct. 1438, 1459-62 (2008). As a
result of this opinion, EPA must take one of three actions: (1) issue a
finding that greenhouse gas emissions cause or contribute to air
pollution that may endanger public heath or welfare; (2) issue a
finding that greenhouse gases do not endanger public health or welfare;
or (3) provide a reasonable explanation as to why it cannot or will not
exercise its discretion to issue a finding. If EPA makes an
endangerment finding, the Clean Air Act requires EPA to regulate
greenhouse gas emissions from new motor vehicles. In response to this
case, EPA has announced that it will issue an Advance Notice of
Proposed Rulemaking on "specific effects of climate change and
potential regulation of greenhouse gas emissions from stationary and
mobile sources under the Clean Air Act.
[41] Cap and trade programs combine a regulatory limit or cap on the
amount of a substance--in this case a greenhouse gas such as carbon
dioxide--that can be emitted into the atmosphere with market elements
like credit trading to give industries flexibility in meeting this cap.
A current example is the cap and trade program for sulfur dioxide under
the Clean Air Act. This program includes electric utilities, which are
the primary emitters of sulfur dioxide, and established a cap on the
utilities' emissions. Sulfur dioxide allowances were primarily given
(rather than auctioned) to companies.
[42] S. 28, S, 309, S. 317, S. 485, S. 1168, S. 1177, S. 1201, S. 1554,
S. 1766, S. 2191,H.R. 620, H.R. 1590, H.R. 3989, H.R. 4226.
[43] GAO, Vehicle fuel Economy: Reforming Fuel Economy Standards Could
Help Reduce Oil Consumption by Cars and Light Trucks, and Other Options
Could Complement These Standards, [hyperlink, http://www.gao.gov/cgi-
bin/getrpt?GAO-07-921] (Washington, D.C.: Aug. 2, 2007).
[44] According to FAA, the last extensive discussion within ICAO on
carbon dioxide emissions from aircraft occurred several years ago. At
that time, ICAO's experts agreed that the cost of fuel provided
sufficient incentive to minimize fuel consumption - hence carbon
dioxide emissions. There was some technical work around 2001 on the
development of an aircraft efficiency parameter, which might have been
used to target carbon dioxide reductions. However, it failed to
identify a parameter that would be able to assess aircraft fleets in
their multiple operational environments in an equitable manner.
[45] The emissions trading scheme involves a cap and trade system that
sets allowances for greenhouse gas emission for industries and other
sources. Parties that pollute below their allowance receive emissions
credits, which they can trade in a market to other parties that have
exceeded their allowance.
[46] The Chicago Convention on International Civil Aviation of 1944
organized global aviation. According to the Convention, no state may
condition the right of transit over or entry into or exit from its
territory of any aircraft of another state on their operator's payment
of fees, dues, or other charges.
[47] For example, FAA notes that there are considerable differences in
the air traffic system efficiencies across the Atlantic, that the
United States has a domestic fuel tax while nearly all EU states have
none, and that the cost of fuel is about 50 percent more expensive for
U.S. airlines because of the dollar's weakness in recent years.
[48] This ongoing work was jointly requested by the Committee on
Transportation and Infrastructure, House of Representatives, and the
Committee on Science and Technology, House of Representatives.
[End of section]
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