By David Jensen"NextGen is here!" That statement made by U.S. Transportation Secretary Ray LaHood in late May is a bit hyperbolized, but there can be no doubt that a major building block for the Next Generation Air Transportation System (NextGen) now officially is here. LaHood's proclamation accompanied an announcement of the Federal Aviation Administration's (FAA's) ruling for equipage for Automatic Dependent Surveillance-Broadcast (ADS-B) "Out."The ruling is one among a number of ADS-B milestones scheduled to occur this year. Indeed, ADS-B technology, which utilizes equipment already installed on commercial aircraft, is set for jet-like acceleration.Resulting from a notice of proposed rulemaking (NPRM) issued in October 2007, the new ruling outlines the functional requirements for ADS-B Out and schedule for equipage. It gives avionics manufacturers the green light to begin building onboard ADS-B equipment, and operators and modification centers to begin working toward supplemental type certificates (STCs) or service bulletins for the equipment's installation. The ruling requires that all aircraft operating in classes A, B, and C airspace around airports and above 10,000 feet be equipped for ADS-B Out by 2020. All aircraft flying above 18,000 feet must be equipped with transponders that transmit the 1090 MHz signal with extended squitter (ES) messaging. A key element of the ruling requires that the transponders meet the minimum operational performance standards (MOPS) outlined in the recently updated DO-260B.Incentive to EquipFAA officials such as Vincent Capezzuto believe the benefits of ADS-B will convince most aircraft operators to equip voluntarily prior to 2020. Capezzuto is ADS-B program manager in FAA's Surveillance and Broadcast Services Office."The 2020 date is to catch stragglers," he says. "We expect people will be equipping sooner." A business case for ADS-B Out, which Capezzuto completed in 2007, makes the "conservative" prediction that 90 percent of the aircraft operating in the U.S. will be fitted with ADS-B-capable avionics by 2018.Other incentives to equip may be forthcoming, though such plans currently appear sketchy at best. "I think we have the White Houseâs attention on [ADS-B and NextGen]," LaHood said during the announcement. "There could be some opportunities to be helpful." Meantime, the incentive to equip, according to Capezzuto, will be operational. It will apply FAA's "best equipped, best served" policy, in which aircraft outfitted for ADS-B will be allowed access to more efficient flight operation. "They can be separated closer and permitted climbs to optimal altitudes sooner," Capezzuto explains. "We could even consider an entire route using ADS-B, something like an HOV lane [on a freeway]."Capezzuto points out that helicopter operators in the Gulf of Mexico have the incentive to be ADS-B equipped. Instead of a procedural separation of 20 nm when flying in poor weather conditions, ADS-B-equipped helicopters can fly just 5 nm apart. Since the flight activity in the Gulf rivals that along the entire East Coast, the savings from reduced separation could be significant. Like the Gulf of Mexico, the Hudson Bay region in Northern Canada has virtually no surveillance radar coverage, which is why operators of the aircraft flying some 30,000 flights over that area also are motivated to be approved for ADS-B Out. Since January 2009, the 250,000 square nautical miles of airspace over the Hudson Bay region has had ADS-B coverage from a system deployed by Sensis Corp. In November, Nav Canada plans to provide separation services over the Hudson Bay region. The agency's controllers will be able to track aircraft flying above 29,000 feet and allow 20-nm separation, a vast improvement over the 80-nm procedural separation. Eventually, all aircraft flying above FL290 over the bay will be required to have ADS-B Out capability, according to a Nav Canada report. Further inducement among international operators to equip may come from a European Aviation Safety Association (EASA) ruling. A notice of proposed amendment (NPA -- like FAA's NPRM) would mandate forward fit of ADS-B Out systems in new aircraft by 2013 and retrofit in fielded aircraft by 2015. On June 10, a meeting of Eurocontrol's Integrated Task Force (ITF)-4 was held in Brussels to finalize recommendations for the NPA, which will be submitted to the European Commission for approval, perhaps by the end of this year. Meanwhile, Airbus, Boeing, and other OEMs are already preparing for the 2013 forward-fit deadline.How it worksA surveillance system with numerous applications, ADS-B is a technology in which an aircraft determines its position using satellite navigation and then broadcasts the position -- along with its altitude, speed, heading, call sign, and aircraft type -- automatically to other aircraft and to air traffic control. In the U.S., two data links exist to broadcast, or transmit, the aircraft's data. Commercial operators would use 1090ES, which is compatible with the Mode S transponders they already are required to have for their traffic alert and collision avoidance systems (TCAS). Airlines will not have to install new antennas and wiring for ADS-B; however, they may have to enter a recertification process, to assure their onboard equipment's accuracy.For the general aviation (GA) community, the ADS-B data link is 978 MHz, often called the Universal Access Transceiver (UAT) link. (Another, regional data link, which uses multiple 25-KHz channels and is called VDL-4, has been developed in Sweden; it is preferred by both that country and Russia.)"For us, the main driver for UAT was to put weather in the GA cockpits," Capezzuto says. While airlines have weather data uplinked from their dispatch and/or operations centers, general aviation aircraft have had a limited source of onboard weather information. The UAT signal for ADS-B will provide weather -- along with NOTAMs, ATIS, and other information -- through a service called Flight Information Services-Broadcast (FIS-B). In addition to FIS-B there exists another uplink service called Traffic Information Services-Broadcast, or TIS-B, which delivers to the cockpit traffic information from air traffic control. Both TIS-B and FIS-B were approved for initial operational capability (IOC) in 2008, following tests using an ADS-B infrastructure (11 ground stations) deployed in southern Florida. Tests leading to the IOC were conducted at the Miami air route traffic control center (ARTCC). TIS-B is part of ADS-B In, which has onboard avionics "taking ADS-B Out information and generating operating tools with it, such as separation and surface management, while providing situational awareness," according to Stephane Chartier, marketing manager for ADS-B products, with ACSS (Aviation Communications and Surveillance Systems), a joint venture company of L-3 Communications and Thales. ADS-B In is viewed to be a major provider of greater airspace capacity and National Airspace System (NAS) throughput. It would reduce, if not eliminate, unnecessary vectoring and increase runway throughput. To achieve ADS-B In capability, an aircraft must be equipped with a receiver, data processing software, and a display.ACSS produces SafeRoute, a set of ADS-B software applications. It is hosted in the company's TCAS 3000SP (Surveillance Processor) product and designed for such applications as surface area movement management (SAMM) and merging and spacing. ACSS's TCAS, in the process of being approved to a DO-260B standard, serves as the receiver required for ADS-B In.With FAA's collaboration, ACSS has recently developed prototype ADS-B In software, called surface indicating and alerting (SURF IA), to help prevent runway incursion. ACSS evaluated surface indicating and alerting functions in 2009 at Philadelphia International Airport. The testing, conducted both day and night, used ADS-B to evaluate distances between aircraft and then show on a cockpit display of traffic information (CDTI), jointly developed by ACSS and Astronautics and displayed on a Goodrich electronic flight bag (EFB), the surface traffic and own-ship position on a map of the airport. "We wanted to make sure that there is data continuity and consistency of alerts, both aural and visual, showing runway color at the right time on the display," Chartier says, explaining the main intent of the tests. FAA and industry working groups are currently developing certification standards for surface movement indication and performance. "We're hoping to see those released by early next year," Chartier adds.SafeRoute also is used to evaluate another ADS-B In application: CDTI Assisted Visual Separation (CAVS) in the terminal area. UPS was the first to have CAVS certified, at the Louisville, Ky., airport, and US Airways plans to begin using it in Philadelphia. Startup in Philadelphia is targeted for late this year. ACSS's CAVS application is certified in visual meteorological conditions (VMC) only. Knowing the aircraft is equipped for CAVS, the controller will allow standard separation even in hazy, VMC conditions and not vector the aircraft out of the approach sequence, according to Chartier. However, CAVS has been successfully demonstrated in a simulator for instrument meteorological conditions (IMC) and, he adds, ACSS hopes the application also will be FAA certified for all-weather use. ACSS's first commercial certification of the SafeRoute system was with UPS in July 2007. The airfreight carrier has six Boeing 757s and five 767s outfitted with SafeRoute software and Astronautics EFBs. "We plan to have the entire fleet [of 211 aircraft] equipped," says Mike Mangeot, a UPS spokesman.In 2008, UPS received FAA approval to test ADS-B applications. The carrier has tested the SAMM and merging and spacing applications, and demonstrated the benefits of reduced fuel consumption, noise, and emissions. "We've calculated that with SafeRoute applications we've saved 250,000 gallons of fuel a year," Mangeot says. "We also gained a 30-percent reduction in nitrous oxide emissions and 34-percent reduction in noise emissions, because we're able to make a continuous descent to the runway."Will FAA follow up its ADS-B Out ruling with an equipage mandate for ADS-B In? It is too early to say; the benefits may become so obvious that they negate the need for an equipage mandate."We submitted a charter to the Office of Rulemaking, and they approved us coming up with an ADS-B In rulemaking committee," Capezzuto says, speaking for the program office. "By September 2011 we would like to have a recommendation of whether to make a rule or whether equipage [for ADS-B In] should be voluntary.â
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