Tag: NextGen

  • GPS: The environment’s unsung hero

    GPS: The environment’s unsung hero

    J. David Grossman
    J. David Grossman

    Can GPS support a greener, more sustainable planet? The answer is an emphatic “yes,” and it is already doing so today.

    GPS has become a fundamental technology across nearly every sector of the U.S. economy, including agriculture, transportation, construction and municipal services. In each of these industries, the use of GPS has produced substantial environmental benefits, such as lowered carbon emissions, increased water efficiency, decreased use of environmentally sensitive inputs, and reduced waste.

    Agriculture

    Let’s take a closer look at how GPS is protecting our nation’s critical environmental resources. We begin with agriculture where it is estimated that the absence of GPS during peak planting season could result in an economic loss of more than $15 billion, according to a National Institute of Standards and Technology report.
    During the past two decades, GPS has transformed American farming, enabling increased crop yields, cost efficiencies, and environmental sustainability through the precise application of seed, water, fertilizers and pesticides and the efficient use of fuel. In sum, precision agriculture lets farmers do more with less wasted seed, less fertilizer, less fuel, less pesticide, and more crop yield.

    GPS Innovation Alliance (GPSIA) founding member Deere & Company reports that precision agriculture technologies can have a huge impact on resource efficiency and sustainability. By 2030, GPS-enabled precision agriculture implemented globally could save 180 billion cubic meters of water, says the World Economic Forum.
    Similarly, according to the U.S. Department of Agriculture’s Natural Resources Conservation Service (NRCS), if “[GPS] guidance systems were used on 10 percent of the planted acres in the United States, fuel use would be cut by 16 million gallons, herbicide use by two million quarts, and insecticide use by four million pounds per year.” For a single Midwest row crop farmer, with 6,500 acres using precision agriculture techniques, Deere & Company estimates that more than 1,600 gallons of fuel could be saved, and more than 400,000 kg CO2 equivalent emissions could be avoided, over the course of a production cycle — the equivalent of nearly a million (992,000) passenger car miles driven per year.

    Infographic: GPS Innovation Alliance
    Infographic: GPS Innovation Alliance

    Construction

    Construction is another industry that has been revolutionized by GPS. Today, high-precision GPS is used to support the building of roads, bridges and other significant infrastructure projects. In 2019, testimony before the U.S. House Small Business Committee, an executive of GPSIA founding member Trimble described several examples of how digital construction technologies, including GPS, can more efficiently plan and execute complex construction projects.

    In one such example from Southern California, the improvements “reduced the wetland impact by 58 acres; reduced the impact to sensitive species; reduced landslide risk; reduced residential displacement; and minimized the impact on existing utilities (resulting in few utility relocations to undisturbed areas).”
    GPS receivers are also embedded in many bulldozers, excavators and graders, resulting in reduced waste and lower fuel consumption. They can reduce greenhouse gas emissions, with an estimate from Trimble suggesting that the use of machine control technologies can cut more than one billion pounds of CO2 usage per year.

    NextGen Air

    GPS is also at the heart of the Next Generation Air Transportation System, or NextGen, of the Federal Aviation Administration (FAA). Capt. Sully Sullenberger, during a 2020 GPSIA-sponsored event, described air traffic control modernization as depending “massively on the ubiquity and reliability of GPS.”

    Along with the safety benefits of knowing the precise location of an aircraft, GPS enables optimized flight paths that the FAA says can reduce “flying time, fuel use, and aircraft exhaust emissions.” These efficiencies have already resulted in $1.2 billion in fuel savings, according to the FAA.

    During a 2010 test flight over Puget Sound, Washington, Alaska Airlines found that the use of GPS-aided flight procedures reduced emissions by 35% compared to a conventional landing. Other airlines have also quantified these benefits, finding substantial savings in fuel consumption simply by cutting a single minute from each flight.

    Weather and Disaster Forecasts

    No one can argue the fact that weather events like hurricanes, floods and droughts have a huge impact on the environment and public safety. According to the National Oceanographic and Atmospheric Administration (NOAA), in 2020 such events cost $95 billion in damages. You may not realize, however, that NOAA uses GPS signals to support three-dimensional meteorology, space weather and geophysical applications throughout the United States.

    Even NOAA’s Geostationary Operational Environmental Satellites (GOES) use GPS signals to enhance their ability to provide the data we all receive in each morning’s TV weather forecast, improving weather predictions and our own storm situational awareness. GPSIA member Lockheed Martin manufactures both the GOES-R series of weather satellites and the U.S. Space Force’s more powerful, next-generation GPS III satellites that are now being launched to modernize the GPS constellation.

    Municipalities

    Lastly, we examine the environmental benefits for municipalities that use GPS for key government services, including the real-time tracking of garbage trucks, snowplows and buses. Throughout the country, towns and cities have seen substantial savings in dollars, fuel and time from implementing GPS-enabled technologies.
    In Niles, Illinois, for example, the Department of Public Works partnered with GPSIA founding member Garmin to optimize the routing of snowplows. Using GPS technology, drivers reduced the use of salt by as much as 40%, resulting in more than 700 tons saved. In 2020, in recognition of its innovative use of GPS, the department received the Management Innovation Award from the American Public Works Association. Similarly, GPSIA member CalAmp found that GPS use for vehicle tracking can result in fuel savings of $90 per vehicle per month.

    Ensuring GPS

    Ensuring these environmental benefits can continue to be realized requires that the spectrum used by GPS be protected from harmful interference. It will also depend on continued funding by Congress to modernize the GPS constellation and ground control. Additionally, as Congress considers a major infrastructure bill, including funding for states and localities, we would encourage projects to make use of GPS and other innovative technologies that can drive down costs, reduce carbon emissions, and eliminate waste — including advanced digital-construction management systems that use GPS data to reduce project costs and speed project delivery.
    GPS has changed our everyday lives for the better, and as our dependence on this technology continues to grow, so will its impact on environmental sustainability efforts.


    J. David Grossman is Executive Director of the GPS Innovation Alliance.

  • A new era begins with geospatially based aviation

    At any given moment, more than 5,000 airplanes are flying over the United States. In a single year, nearly 778 million passengers will take to the skies — more than twice the population of the U.S., and the number increases each year. Aviation is the safest form of transportation. It is 100 times safer than driving. For every 100 traffic deaths, only one aviation related fatality occurs; and the Federal Aviation Administration (FAA) is working hard to make aviation even safer.

    Safety is the FAA’s primary focus. The FAA Strategic Plan FY 2019– 2022 states its mission is to provide the safest, most efficient aviation system in the world. To achieve this goal, the FAA is implementing several initiatives. The technical aspects of these efforts fall under a framework called NextGen designed to modernize the nation’s air traffic control system. NextGen began in 2003 in the VISION 100 – Century of Aviation Reauthorization Act. At its core, NextGen is a geospatial framework with satellite navigation as its backbone.

    The Geospatial Data Act (GDA) became law when President Trump signed the FAA Reauthorization on Oct. 5, 2018. You might have wondered how the GDA came to be included in the bill. It makes sense in the context of technology advancements towards a smart transportation network, specifically in aviation.

    The smart transportation concept integrates all forms of transportation to provide economic and environmental benefits as well as increase safety and reduce wait times and congestion. A large part of smart transportation is based on geographic information technology. The aviation component of this smart transportation initiative falls within the FAA’s authority under the overarching framework named NextGen.

    NextGen is an integrated concept improving the efficiency and safety of flight operations both on the ground and in the air. The use of geospatial technology enables precision time-management for controlling air traffic. The system allows each airplane to digitally coordinate with other aircraft in the area, taking into account such things as terrain and other known hazards to safely reroute air traffic as necessary. The FAA refers to this as trajectory-based operations. Those with a knowledge of GIS will recognize it as four dimensional: it calculates direction, speed, distance and time relative to position in x-y-z, and coordinates that information with other known data. Additionally, the system uses historical flight data and predictive analytics to maximize airspace for routing air traffic such as what is experienced during the holidays.

    NextGen also uses a system called Optimal Profile Descents (OPD), which allows an airplane to trim its engines and descend along a glide slope from flight level into the airport. The point at which a plane begins its descent is a geospatial calculation to determine the precise point in space for the airplane based upon its altitude, weight, glide slope and distance to the airport. The benefits of OPD are reduced engine noise, fuel savings, less carbon emissions and a positive economic impact. NextGen is an across-the-board win for the airline industry, airline passengers, the economy and the environment.

    According to an interview with Michael Whitaker, former deputy administrator of the FAA who was the Chief NextGen Officer, NextGen revolutionizes aviation by enabling digital data communication. It replaces radar-based navigation and tracking with satellite-based air traffic control. The cornerstone of NextGen is the Automated Dependent Surveillance Broadcast (ADS-B) system.

    ADS-B is an aviator’s version of Waze, but with a lot more information. ADS-B(out) broadcasts an airplane’s Flight ID, ICAO Code, speed and location in three-dimensional space to air traffic controllers and to everyone who is equipped with ADS-B(in). The combination of ADS-B(out) and ADS-B(in) greatly increases situational awareness for aviators. On Jan. 1, 2020, all airplanes operating in controlled airspace needed to have ADS-B(out) installed. ADS-B transforms the entire National Airspace System into a satellite-based geospatial network. It integrates multiple sources of real-time data, such as weather, pilot reports, aircraft positions, 3D airspace information, and other sources of data, which can be overlaid on top of various basemaps and terrain elevation models, allowing pilots to make more informed and safer decisions.

    Switching to ADS-B opens up more capacity in already crowded skies by decreasing the required vertical and horizontal separation distances between aircraft. At Hartsfield-Jackson International Airport, the busiest airport in the world, changing to performance-based operations allowed 8 to 12 more departures per hour; and in Memphis International Airport, one of the busiest airports for cargo operations, arrivals increased by 20%.

    Rune Duke, senior director of government affairs, Airspace, Air Traffic and Aviation Security for the Aircraft Owners and Pilots Association (AOPA), said that ADS-B will allow much faster update rates for air traffic controllers on the order of once every second, compared to legacy radar systems that report positions every 8 to 12 seconds. For an airplane traveling at 350 knots, that is about 1 mile. A lot can change in a mile in densely packed airspace.

    If you are reading this because of your love of maps and aviation, then I highly recommend the FlightAware and ForeFlight smartphone apps. FlightAware turns the phone into an ADS-B(in) receiver showing the location and flightpath of each aircraft in the immediate area on a basemap. I sit on my back deck and watch airplanes coming and going because I live under the flightpaths for Dulles International Airport, Reagan International Airport, Leesburg Executive Airport, the Montgomery County Airpark and the TERPZ waypoint. On occasion I see helicopters flying to Camp David because I am under that flight path as well.

    So, I get to see a variety of aircraft. You can select the airplane icon to see information such as aircraft type, airline, Flight ID, departing and arrival airports, altitude, and groundspeed. Even more information is available by selecting the pop-up window. This is ADS-B information. ForeFlight, on the other hand, is a pilot’s flight bag on a tablet.

    In the future, ADS-B will integrate Aircraft Hazardous Areas (AHA): temporary no-fly zones due to commercial space launches. Because of ADS-B, planes will automatically reroute around the AHA, and when the AHA expires, airplanes will be routed back through the area.

    ADS-B supports evolving technologies such as remote towers, another significant change to air traffic control. Remote towers allow air traffic controllers to be at a location other than the actual airfield. Remote towers use a suite of sensors mounted at the airfield, including high-definition video, thermal and night vision that can be combined with the digital information provided by ADS-B, all of which is displayed on widescreen panels in a room duplicating the experience of being at the airport and directing aircraft. This allows smaller airports that cannot afford the huge expense of building and staffing an air traffic control tower to be part of a remote tower network. One remote tower center will be able to support several airfields. Leesburg Executive Airpark recently finished successful testing of one of the first remote tower operations in the United States.

    “Over the next 10 years, we are going to see logistics and transportation open up, from being limited by currently rigid road infrastructure to operating on fully flexible and responsive aerial transportation networks,” said Patrick Watson, director of business development for Animal Dynamics.

    The envisioned Platform Unmanned Cargo Aircraft. (Photo: PUCA
    The envisioned Platform Unmanned Cargo Aircraft. (Photo: PUCA)

    ADS-B will also support the integration of unmanned aerial systems (UAS) into the airspace, specifically unmanned cargo aircraft (UCA). In the not too distant future, carrier air fleets without pilots or aircrew will be taking to the skies. UCAs do not require crews, so there will be no need for water, toilets, sewage containment, kitchens or a cockpit (in the traditional sense). Taking those out will allow for more space in the plane to carry cargo and fuel. Plus, without crews on board, there will be no time restrictions on crew hours — planes will be able stay aloft longer and travel further. ADS-B greatly enables the success of this technology.

  • FAA awards NextGen contract to Lockheed Martin

    The Federal Aviation Administration (FAA) has awarded a contract to Lockheed Martin worth $344 million to develop and implement a new NextGen technology that will improve the efficiency of departures and arrivals, as well as the movement of aircraft on the ground.

    The new technology is expected save time for the flying public and lessen the impact on the environment by reducing emissions and noise.

    Terminal Flight Data Manager (TFDM) will replace the paper flight strips that air traffic controllers currently use at most airports to share flight plans with electronic flight strips that will enable faster and more informed tactical decisions. The electronic strips will improve work efficiency, making it easier for controllers to accommodate traffic volume changes, bad weather and other evolving situations.

    With TFDM, the digital flight plans used to estimate arrivals, gate push-backs, routings, departures and overall airport demand will be shared in real time among air traffic controllers, aircraft operators and airports to improve the handling of more than 40,000 flights each day.

    The shared awareness of aircraft on the ground and in the air will enable arrivals, departures and surface flow to be managed more efficiently, providing accurate, predictive modeling tools to improve flight efficiency from gate to gate.

    Other benefits include improved aircraft traffic flow on the ground, which maximizes airport efficiency, reduced taxi-time delays, and enhanced safety through an increase in controllers’ heads-up time.

  • CMD Flight gains FAA approval for ADS-B solution

    CMD Flight Solutions has received U.S. Federal Aviation Administration (FAA) approval on its third Collins TDR-94/94D Transponder and GPS pairing, the FreeFlight Systems WAAS 1203C.

    CMD Flight Solutions develops, markets and provides FAA-certified modifications to support NextGen avionics mandates and assists service and installation facilities with modification solutions to satisfy FAA-mandated requirements. The company provides Automatic Dependent Surveillance-Broadcast (ADS-B) Out on more than 5,000 business and personal aircraft.

    The supplemental type certificate (AML STC) of its ADS-B OUT solution for Part 25 airplanes covers installation of FreeFlight’s 1203C SBAS/GNSS GPS position sensor with Rockwell Collins TDR-94/94D transponders. According to FreeFlight, “The pairing is a cost-effective way to help aircraft owners meet the ADS­-B mandate.”

    ADS-B OUT compliance is due Jan. 1, 2020, in the United States.The 1203C, a 15-channel GPS sensor, is also an approved position source for NextGen applications such as CPDLC, TAWS/FMS, RNP and others.

  • QantasLink selects FreeFlight SBAS/GNSS sensor for ADS-B compliance

    waas_1203QantasLink, Australia’s largest regional airline, has selected the FreeFlight 1203C SBAS/GNSS sensor for retrofit into its DHC-8-200/300 series of aircraft.

    QantasLink paired the 1203C with the Dash 8’s TDR-94D Mode-S transponders.

    “We’re pleased to demonstrate once again that there are practical ADS-B solutions for aircraft that have been in service for a while,” said Pete Ring, FreeFlight Systems’ director of Sales and Marketing. “We are proud to supply QantasLink with a straightforward, retrofit solution that extends the life of their DHC-8 fleet.”

    As a certified ADS-B position source approved for all ICAO jurisdictions, the integrated 15-channel 1203C SBAS/GNSS sensor is part of a fully rule-compliant ADS-B Out system when paired with a compatible certified Mode S transponder like the TDR-94D. Providing reliable service to fleets worldwide, the 1203C also serves as the approved position source for CPDLC, TAWS/FMS, RNP and other NextGen applications.

    Designed for business, regional, airline transport and heavy rotary wing aircraft, the 1203C provides state-of-the-art aviation GPS technology in a proven package. The 1203C allows customers to take advantage of the benefits of NextGen without the need for extensive and costly avionics upgrades.

    Founded in 2001 and based in Texas, the company pioneered the first certified aviation WAAS/GPS receiver and the first rule-compliant UAT ADS-B system. FreeFlight Systems designs and manufactures high-performance avionics for flight safety. The solutions deliver substantial safety, cost, environmental and other benefits from the NextGen airspace transformation.

  • Expert Advice: Which Is the Best GNSS Receiver?

    Expert Advice: Which Is the Best GNSS Receiver?

    Jaynata Ray
    Jaynata Ray

    By Jayanta Ray

    Aerospace GNSS receivers constitute a class apart, compared to their more popular relatives used in automotive, cell phone, or survey applications. Automotive and cell-phone receivers can sometimes provide position information even in indoor environments. The survey class of receivers provides centimeter-level accuracies. However, neither group can guarantee the reliability and integrity of the position solution, and users rely upon them at their own risk, and only in non-critical applications.

    On the other hand, an aerospace GNSS receiver not only provides decimeter-level accuracy, but it also guarantees that the position error is bounded by an integrity limit. The probability that the position error is more than the integrity limit is very rare: one in ten million times.

    Now, isn’t that the best class of GNSS receiver?

    A certified aerospace GNSS receiver stands as the keystone of the Federal Aviation Administration’s (FAA’s) ambitious NextGen Aviation program for the United States. The FAA developed NextGen to revolutionize the way an aircraft flies in the U.S airspace. In its June 2013 update report, the FAA states that “NextGen is providing major benefits to the general aviation community. The Wide-Area Augmentation System (WAAS) has improved general aviation access to more than 1,500 airports in all kinds of weather with no costly investment in ground infrastructure.”

    According to the report, by the end of the NextGen mid-term in 2020, NextGen improvements will reduce delays by 41 percent from today. The FAA estimates that by 2018, NextGen will reduce aviation fuel consumption by 1.4 billion gallons, reduce emissions by 14 million tons, and save $23 billion in costs. NextGen also has an important safety impact for air travelers.

    Tens of thousands of aircraft are already equipped with WAAS receivers, which improve the availability, accuracy, and integrity of GPS signals. Pilots take advantage of WAAS technology to fly approach procedures using Localizer Performance with Vertical Guidance (LPV) to altitudes as low as 200 feet. The FAA has published 3,123 WAAS LPV approaches as of May 2013 and expects to publish 5,218 by 2016.

    The key to NextGen is the aerospace GPS-SBAS receiver.

    How different are aerospace GNSS receivers from commercially available receivers, including high-precision receivers?

    An aerospace GPS-SBAS receiver is characterized by very high reliability, accuracy, and availability. Among these attributes, the reliability factor is the most important parameter. Misleading information from an aerospace receiver should be extremely improbable, since that can lead to hazardous or severe major consequences to the aircraft, its passengers, and flight crew.

    Table 1 shows the major differences between a standard GNSS receiver and an aerospace GNSS receiver.

    Table 1 Differences between a standard GNSS receiver and an aerospace GNSS receiver.
    Table 1. Differences between a standard GNSS receiver and an aerospace GNSS receiver.

    Performance Requirements

    The DO-229D standard document — formally, the RTCA Minimum Operational Performance Standards for GPS/WAAS Airborne Equipment — specifies the minimum performance standards of an aerospace GPS-SBAS receiver. In particular, an aerospace GNSS receiver needs to meet the GPS and SBAS signal processing requirements, GPS and SBAS data/message processing requirements, satellite integrity status requirement, accuracy requirements in presence of interference, dynamic range and sensitivity requirements, and so on, as defined in DO-229D standard.

    Most importantly, the receiver must meet the Receiver Autonomous Integrity Monitoring (RAIM) requirements for en-route, terminal, non-precision and precision phases of flight of DO-229D. Additionally, the receiver must meet the fault detection, fault exclusion, missed alert, false alert, step detection, ramp detection, and other integrity-related requirements of DO-229D.

    Further, the receiver needs to meet the environmental conditions specified in DO-160 standard for temperature, temperature variation, altitude, humidity, shock, vibration, magnetic effects, voltage spike, EMI/EMC, lightning, and so on.

    Safety and Reliability Aspects

    A Functional Hazard Assessment (FHA) based on the intended function of the GPS-SBAS receiver software needs to be carried out to determine whether the receiver meets the requirements of hazardously misleading information. The safety and reliability aspects of the receiver are computed through Failure Mode and Effect Analysis (FMEA) and Fault Tree Analysis (FTA). The effects of each failure mode are determined at the system level for each operating mode of the equipment.

    RAIM.  For an aerospace GPS-SBAS receiver, RAIM is of paramount importance. The measure of protection provided by RAIM is given by Horizontal/Vertical Protection Limits (HPL/VPL). HPL is used as the protection limit for en-route, terminal, and LNAV (Non-precision approach) phases of flight and compared against the Horizontal Alert Limit (HAL) for the phase of flight. Whereas, VPL is compared against the Vertical Alert Limit (VAL) for the LNAV/VNAV and LP/LPV phase of flight.

    The most critical part of the integrity requirement is to detect a satellite failure and, if possible, to make corrective actions in addition to generating timely alerts. A Failure Detection and Exclusion algorithm, often known as FD/FDE, is to be implemented in an aerospace GNSS receiver. The effectiveness of the FD/FDE algorithm has to be tested extensively in off-line condition for availability of satellite failure detection and exclusion. Further, the algorithm has to be tested in on-line conditions as well as on a target environment. There has to be a match among the off-line,
    on-line, and on-target test results for using the algorithm in
    the GNSS receiver.

    The integrity tests on an aerospace GNSS receiver are carried out as per the guidelines in DO-229D. This requires simulation of the GPS orbit and determination of satellite visibility at more than two thousands grid points on the Earth surface and for 12 hours at 5-minute time intervals. The FD/FDE algorithm is validated at each space-time point to determine the availability of failure detection and exclusion.

    For the non-precision approach, the space-time points are arranged in terms of the HPL values and Horizontal Exclusion Limit (HEL) values and the most difficult to detect/exclude satellite is identified. Extensive Monte Carlo simulations are carried out at the selected space-time points to validate the false alert and missed alert requirements of DO-229D standard. Similar tests are carried out on the GNSS receiver for the precision approach, wherein the VPL values are considered instead of HPL values. Further, the test results of the off-line tests are validated through comprehensive on-line and on-target tests on the selected space-time points.

    Certification Aspects

    To ensure that the software and the firmware of the aerospace GNSS receiver are robust, providing adequate levels of safety and reliability, the receiver software and firmware need to be developed conforming to the software and hardware design assurance standards — DO-178B and DO-254 respectively. Based on the criticality of the end application, the design assurance should meet DO-178B and DO-254 objectives of Level A, B, or C criticality.

    An aerospace GNSS receiver needs to be certified by the FAA (or other competent authorities in other countries) for airworthiness. The FAA gets involved in the certification process right from the planning stage and oversees the compliance of the entire development process as per DO-178B and DO-254 standards. The aerospace GNSS receiver software and firmware undergo extensive verification and validation processes. Further, the GNSS receiver is subjected to all the functional and environmental tests as per DO-229D and DO-160 standards respectively under FAA supervision. Only after the successful completion of all the software, hardware, and systems tests, the receiver is certified by the FAA for airworthiness through Technical Standard Order TSO-C145 Authorization (TSOA).

    Conclusion

    Aerospace GNSS receivers, by virtue of their inherent safety, reliability, and integrity, are far more suitable for critical applications, where an error could have hazardous or catastrophic consequences. These receivers must be used in commercial transport aircraft, business jets, general aviation aircraft, gliders, experimental aircraft, balloon, and so on. Further, in airport surface vehicles and mass-transport vehicles such as high-speed trains, trams, and unmanned autonomous vehicles of all sorts, whether ground or air, receivers similar to aerospace GNSS receivers should be used for navigation and surveillance purposes.


    Jaynata Ray received his Ph.D. from the University of Calgary. He has worked in the GPS field since 1992, and is group manager at Accord Software and Systems in Bangalore, India. He is a member of GPS World’s Editorial Advisory Board.

  • Denver Airport Begins Arrivals and Departures with NextGen

    Denver International Airport (DIA) has fully implemented its new arrival and departure procedures, the next phase in the Federal Aviation Administration’s mass overhaul of U.S. airspace, called NextGen. Denver is among the airports at the front end of the adoption process, and is highlighted in an in-depth feature in the Denver Post.

    According to the article, “The recently completed phase at DIA trims arrival and departure fuel costs by eliminating several intermediary steps. The traditional system requires an airplane to come into and out of cruising altitude by firing its thrusters at every new altitude level, wasting hundreds of pounds of fuel… The traveling public will not likely notice an immediate difference in travel time, but proponents hope that the early investment pays off in the end.”

    The FAA predicts that NextGen improvements will reduce flight delays by 38 percent and lead to a 1.4-billion-gallon total reduction of fuel burn by 2020.