Automatic Dependent Surveillance - Broadcast (ADS-B) Out Performance Requirements to Support Air Traffic Control (ATC) Service

Transcription

1 Automatic Dependent Surveillance - Broadcast (ADS-B) Out Performance Requirements to Support Air Traffic Control (ATC) Service Docket No. FAA COMMENTS OF THE AIR TRANSPORT ASSOCIATION OF AMERICA, INC. March 3, 2008 TABLE OF CONTENTS I. INTRODUCTION... 1 II. INTEREST OF ATA... 2 III. EXECUTIVE SUMMARY... 2 A. ADS-B has Potential to Improve the NAS Efficiency and Safety... 3 B. The NPRM is Materially Deficient... 3 C. Key Recommendations of the Air Transport Association IV. REVIEW OF THE PROPOSED REGULATION... 5 A. Either of Two Avionics Systems Would Provide Compliance with the Proposal... 5 B. The Proposal Would Establish a Dual-Link ADS-B Out System C. The Proposal Implies a Prescriptive Requirement... 6 V. CONCEPT PLANS OF THIS RULEMAKING ARE UNIQUE AND REQUIRE UNIQUE ACTIONS... 6 A. FAA Should Conclusively Vet with Industry the Dual-Link Concept B. FAA Should Develop Financial Incentives to Support the ADS-B Program... 7 C. Establish a Two-Phase Implementation of ADS-B Out, and Accelerate the Availability of Benefits... 7 D. ADS-B Deployment Requires Concurrent Development and Implementation Programs... 8

2 1. FAA Should Formally Commit to Dates for the Availability of ADS-B Out Operational Applications The FAA Should Approve Initial Standards Harmonized with Existing ADS-B Operations The FAA Should Perform Advanced R&D to Establish ADS-B In Standards by E. FAA Should Better Coordinate with JPDO for NextGen Initiatives F. Detailed Technical Requirements should be in Airworthiness Standards VI. ATA RECOMMENDS CHANGES TO CERTAIN PROVISIONS OF THE PROPOSED OPERATING RULE A. Global Harmonization Other Nation Navigation Systems and Interoperability FAA Should Provide for Initial Position Sensor Standards in Lieu of WAAS FAA Should Advocate Changes to Certain National Policies for GPS B. Certain Actions are Necessary to Accelerate the Availability of ADS-B Benefits Commit to the Continuous Availability and Expansion of Radar-Like Traffic Separation Standards Approve the Most Beneficial Initial Operations by Action is Needed to Support ADS-B Operations in the Gulf of Mexico Determine by 2010 which Non-ADS-B Avionics Could be Replaced by ADS-B Equipage Establish Preferred Routes for ADS-B-equipped Airplanes FAA Has Released an ADS-B Out Economic Decision Tool for Operators Establish Agreements with Operators For Demonstrations C. Industry Requests Additional Information on Proposed Preflight Actions D. Evaluate the Potential Surface Safety Enhancements of ADS-B Out ii

3 VII. COMMENTS REGARDING TECHNICAL FACTORS A. Identify Existing Position Sources and Transponders Capable of Achieving Benefits Early B. Multilateration Should Augment ADS-B for Surface Applications VIII. COMMENTS REGARDING ECONOMIC VALUE AND IMPACT A. ATA Performed an Analysis of the Impact of Retrofitting Large Commercial Transports B. The Impact of Retrofitting ADS-B Out is Twice FAA Estimates Position Sensors May Have the Most Significant and Enduring Impact The Impact of Adding ADS-B In Would Surpass the Impact of ADS-B Out IX. CONCLUSION APPENDIX A: APPENDIX B: Minimum Broadcast Message Element Set Table ATA Surveys, Fleet Forecast and Program Cost Estimates 1. Forecast Retrofit Schedule for ATA-Member Fleets... B Consolidated Results of Member Surveys... B Fleet Forecast of the Fleets of ATA-Member Airlines... B ADS-B Out Retrofit Costs for a Forecasted ATA Fleet... B-81 iii

4 March 3, 2008 U.S. Department of Transportation 1200 New Jersey Avenue, SE West Building, Ground Floor, Room W Washington, DC Re: Automatic Dependent Surveillance -- Broadcast (ADS-B) Out Performance Requirements to Support Air Traffic Control (ATC) Service, 72 Fed. Reg (proposed October 5, 2007); Docket No. FAA I. INTRODUCTION The Air Transport Association of America, Inc. (ATA) 1 submits these comments in response to the above-referenced Notice of Proposed Rulemaking (the NPRM or proposal). The NPRM proposes to amend the General Operating and Flight Rules in 14 CFR Part 91, applicable to aircraft operated in United States airspace, to require avionics that support improved surveillance by Federal Aviation Administration (FAA) and Department of Defense air traffic controllers. Specifically, the proposed rule would set performance standards for Automatic Dependent Surveillance - Broadcast (ADS-B) Out systems and would require that such systems be installed in aircraft in order to operate in specified classes of airspace within the United States National Airspace System (NAS). The proposed avionics also would enable ADS-B In and other elements of an envisioned Next Generation Air Transportation System (NextGen), although ADS-B In is not specifically addressed in the NPRM. 1 Members are: ABX Air, Inc.; Alaska Airlines, Inc.; Aloha Airlines; American Airlines, Inc.; ASTAR Air Cargo, Inc.; Atlas Air, Inc.; Continental Airlines, Inc.; Delta Air Lines, Inc.; Evergreen International Airlines, Inc.; Federal Express Corporation; Hawaiian Airlines; JetBlue Airways Corp.; Midwest Airlines, Inc.; Northwest Airlines, Inc.; Southwest Airlines Co.; United Airlines, Inc.; UPS Airlines; and US Airways, Inc. Associate Members are: Air Canada, Air Jamaica Ltd. and Mexicana.

5 II. INTEREST OF ATA ATA is the principal trade and service organization of the U.S. scheduled airline industry, and its members account for over ninety percent (90%) of the passenger and cargo traffic that U.S. scheduled airlines carry annually. ATA s members provide a full range of domestic and international commercial air transportation services for passengers and shippers with a combined fleet (currently) of 4,288 aircraft. The proposed rule would apply to all airplanes that ATA members maintain and operate and all their future airplane acquisitions. Thus, ATA and its members have a vested interest in the outcome of this rulemaking. ATA members also have a direct and material interest in the efficiency, capacity and safety of the NAS. As FAA is well aware, important sectors of the NAS often approach and sometimes exceed current capacity limits, especially when weather affects the system, which causes flight delays, inefficient routings and increased fuel consumption, in order to maintain the highest level of system safety. ADS-B deployment and NextGen offer significant improvements over the existing outdated, radar-based ATC system. These additional reasons drive ATA s interest in this rulemaking proceeding. III. EXECUTIVE SUMMARY ATA strongly supports ADS-B technology and the development and deployment at the earliest possible date of the NextGen system. ATA consistently has expressed the view that ADS-B is a foundational technology for NextGen. We appreciate the FAA s extensive, ground-breaking work underlying the ADS-B NPRM, much of which is not credited in the proposal. However, our principled support for ADS-B and NextGen must give way in this instance to our concerns that the NPRM is poorly conceived and, as a result, will not serve the public interest in a modern ATC system that increases airspace capacity and reduces aviation s impact on the environment. We are also concerned that the NPRM, if implemented as proposed, will not produce a benefit to regulated parties (and, by extension, to the traveling and shipping public) but will, on the other hand, commit the aviation industry to enormous costs. Thus, as discussed in detail below, the NPRM fails to meet important substantive objectives and it also fails to satisfy crucial administrative requirements. Its lack of an appropriate implementation program and relevant airworthiness standards, and its dual-link architecture cause specific concerns. For these reasons, ATA recommends that FAA publish a supplemental NPRM that establishes an appropriate standard for ADS-B performance and deploys ADS-B Out in two phases. ATA s proposal will, in fact, accelerate the public benefits of ADS-B technology and advance the understanding of all stakeholders FAA, airlines, aircraft manufacturers and avionics manufacturers concerning the capabilities and limitations of ADS-B Out technology while providing important information for developing ADS-B In standards and applications. This will also reduce the risk of additional equipage changes for ADS-B In in the future. 2

6 A. ADS-B has Potential to Improve the NAS Efficiency and Safety. Conceptually, ADS-B Out could significantly improve air traffic surveillance by providing controllers with near real-time, continuous and highly accurate position reports from nearly all air traffic. Thus, the ADS-B surveillance picture would support closer and more precise control of air traffic than possible with existing ground radar systems, including traffic beyond radar coverage. With corresponding upgrades to operating standards and procedures, ADS-B Out could improve the efficiency, capacity and safety of the NAS, and enable further improvements envisioned for NextGen. B. The NPRM is Materially Deficient. While ATA in concept fully supports NextGen and ADS-B technology we have significant concerns with several aspects of the proposal and recommend that the FAA issue a supplemental NPRM. The proposal does not measure up to the task of updating our national airspace system (NAS). We echo many of the concerns identified by the ADS-B Aviation Rulemaking Committee (ARC), airplane manufacturers, avionics suppliers, and the Department of Transportation s Inspector General. 2 Our primary concerns stem from FAA s issuance of this NPRM: requiring carriers to equip to a standard that is neither necessary nor proven, at a time when ADS-B technology is continuously evolving; (2) without FAA committing to provide operational benefits for airspace users until after 2019, 3 and; (3) without the benefit of stakeholder input. The ATA applauds FAA s formation of the ADS-B ARC, which may help resolve industry concerns, but adds that these concerns could have been precluded had the ARC been formed in time to advise FAA in the development of the proposal. We look forward to working with FAA and other industry members to develop the best path to reaching everyone s goal of NextGen and ADS-B. C. Key Recommendations of the Air Transport Association. The ATA respectfully submits a number of specific recommendations that are important to successfully implementing ADS-B. They are intended to describe and facilitate a two-phase 2 See Statement of The Honorable Calvin L. Scovel III, Inspector General U.S. Department of Transportation, Challenges Facing the Implementation of FAA s Automatic Dependent Surveillance-Broadcast Program before the Committee on Transportation and Infrastructure Subcommittee on Aviation United States House of Representatives, October 17, See Draft Regulatory Impact Analysis, Draft Regulatory Flexibility Analysis, International Trade Impact Assessment, and Unfunded Mandates Assessment, Automatic Dependent Surveillance-Broadcast (ADS-B) Out Performance Requirements to Support Air Traffic Control Service, Office of Aviation Policy and Plans, Operations Regulatory Analysis Branch, October 1, 2007 ( Regulatory Evaluation or Reg Eval ), page 80. 3

7 development and implementation program that would provide a mechanism for addressing several open issues with the proposal including natural disincentives for airspace users to equip, interoperability, and most importantly, ways to gain aviation community and public confidence in the program by providing operational benefits much sooner than proposed. The following recommendations are, in our view, key prerequisites and elements for a sound two-phase approach. Many are aligned with recommendations in the ARC Report: 4 1. Develop financial incentives for airspace users to support ADS-B and the recommended program, below, of in-service demonstrations and evaluations. 2. Task the ARC to develop a supplemental NPRM that specifies a two-phase implementation of ADS-B, to be competed by 2020, as follows: Phase 1 Vet with industry the dual-link ADS-B concept and the role of the Wide Area Augmentation System (WAAS). Approve initial technical standards for ADS-B Out position sensors and transponders that are consistent and compatible with Australian, Canadian and European standards. (ie, TSO-C129a for position sensors, and RTCA DO-260 with a specified message element set for transponders). Establish in conjunction with this rulemaking an accelerated schedule for the availability of traffic control services for ADS-B Out equipped airplanes that provides radar-like traffic separation, expands those services to areas currently having no or limited radar coverage, and makes available services providing better-than-radar traffic separation. Commit to the schedule in the Rule. Coordinate with operators to conduct initial ADS-B Out demonstrations at specific airports and areas where users can provide a critical mass of equipped airplanes. FAA should share equipage costs and facilitate necessary operational approvals. Coordinate with industry to perform in-service demonstrations and evaluations to validate advanced ADS-B Out operational concepts to establish better-than-radar separation standards. Coordinate with industry to perform research and development (R&D) simulation and modeling and in-service demonstrations and evaluations to validate advanced ADS-B In operational applications and further improved separation standards and user benefits, and to establish ADS-B In performance standards. 4 Optimizing the Benefits of Automatic Dependent Surveillance-Broadcast, Report of the ADS-B Aviation Rulemaking Committee, October 3, 2007; ADS-B ARC Report. 4

8 Coordinate with appropriate Federal agencies to commit to a minimum of 27 operable satellites in the GPS constellation, and to provide a defined schedule for the deployment of the planned dual-frequency GPS constellation. Phase 2 Adopt performance standards for transponders and position sensor accuracy and integrity if necessary to perform the advanced ADS-B Out applications validated in Phase 1. Standards should be harmonized with international standards, and should not be mandated for operations before the proposed 2020 compliance date. Publish technical standards for ADS-B avionics in airworthiness standards regulations. Coordinate with industry to establish implementation plans for ADS-B In. IV. REVIEW OF THE PROPOSED REGULATION A. Either of Two Avionics Systems Would Provide Compliance with the Proposal. The proposal would amend 14 CFR Part 91 to require aircraft to be equipped with ADS-B Out in order to operate, after 2019, in most U.S. controlled airspace. In general, the requirement would apply to the same types of aircraft and operations that currently require a transponder. Technical requirements for ADS-B Out avionics would be as specified in Technical Standard Order (TSO) C166a or later for 1090 MHz (extended squitter) ADS-B Out systems, and TSO-C154b or later for 978 MHz ADS-B Out systems. In turn, the TSOs refer to RTCA Standard DO-260A, Change 2 for 1090 MHz systems and DO-282A, Change 1 for 978 MHz systems. FAA explains in the preamble that compliance with these change versions of the RTCA standards would be necessary to meet the performance requirements specified in proposed Part 91, 5 Appendix H, including requirements for position sensor accuracy and integrity; transponder message element set requirements; and latency limits for certain avionics. Certain system requirements are specified solely in the proposal, and FAA has supplemented the proposal with a draft advisory circular (AC). 6 The 1090 MHz system would be required for operations at or above flight level 240. B. The Proposal Would Establish a Dual-Link ADS-B Out System. Operators could equip with the 1090 MHz extended squitter (1090 ES) system, the 978 MHz Universal Access Transceiver (UAT), or both. The UAT system can include Traffic Information 5 72 Fed. Reg. 193, page FAA published draft Advisory Circular (AC) 20-ADS-B for comment on December 19,

9 Services-Broadcast (TIS-B) and Flight Information Service-Broadcast (FIS-B). A ground-based Automatic Dependent Surveillance-Rebroadcast (ADS-R) system would compile and broadcast positions reported by aircraft equipped with either 1090 ES or UAT and aircraft not equipped with either providing a dual link. Operators of large commercial transports already have systems that provide sufficient traffic and flight information, and likely would equip with 1090 ES systems. Other operators who could benefit from TIS-B and FIS-B likely would equip with UATs. C. The Proposal Implies a Prescriptive Requirement. The NPRM proposes a performance-based operating rule. However, the FAA stated that, Presently, GPS augmented by the Wide Area Augmentation System (WAAS) is the only navigation position system that provides the level of accuracy and integrity to enable ADS-B Out to be used with sufficient availability. 7 This statement clearly has the effect of prescribing a compliant system for aircraft certification, and presumes a reduced availability of the GPS satellites. V. CONCEPT PLANS OF THIS RULEMAKING ARE UNIQUE AND REQUIRE UNIQUE ACTIONS A. FAA Should Conclusively Vet with Industry the Dual-Link Concept. ATA is also concerned with the ADS-B proposed dual-link approach. Central to the approach is the ADS-R system, which can introduce system-wide latency into the position reports and data it exchanges between aircraft on different ADS-B frequencies (i.e., on 978 or 1090 MHz), 8 and which poses a potential single point failure for the degradation or loss of surveillance data. The proposal identifies no experience with an ADS-R system. The system s risks of latency and degradation can only limit the potential separation and efficiency improvements that ADS-B could provide. ADS-R also could reduce or eliminate any future possibility of streamlining Traffic Alert and Collision Avoidance System (TCAS) equipage requirements with ADS-B technology. Further, the dual-link approach would require two types of transmitters on ground equipment, which would unnecessarily complicate potential ADS-B surface applications. ADS- R could broadcast the positions of aircraft having no ADS-B transponder; however, this would add no value until ADS-B In is defined and installed in aircraft. Dual-link would incur increased program costs, complexity of systems and operations, 9 and a disregard for certain international standards, which do not use the UAT frequency. A single-link system in which all aircraft were 7 72 Fed. Reg. 193, page Fed. Reg. 193, page 56953, discusses the latency inherent in an ADS-R system. 9 The proposed dual-link also may incur unintended consequences by applying operating limits only to certain airspace users solely based on avoidable differences in the characteristics of their transponders. 6

10 equipped with 1090 ES (Mode S) transponders would eliminate the need for ADS-R, and avoid a premature and unnecessary assumption of the risks of cost, complexity and vulnerabilities of the dual-link concept. Operators desiring the UAT s TIS-B or FIS-B could acquire those services through XM radio or other sources without inducing the system-wide issues, risks and costs of dual-link. Before adopting the proposal, the FAA should conclusively vet with stakeholders the efficacy of the dual-link concept and regulatory compliance using UATs. B. FAA Should Develop Financial Incentives to Support the ADS-B Program. As discussed in Section VIII, the proposed rule would not specifically obligate FAA to facilitate user benefits until after 2019, when all airplanes were equipped with ADS-B Out. At that time, airspace users could begin accumulating returns on their investments provided that FAA reduces radar traffic separation standards and also applies those standards to areas which currently have no radar coverage. The Regulatory Evaluation assesses potential limited benefits that may be available before 2020, but the proposed rule would provide no guarantee that those benefits could be realized. In addition, there is a natural incentive for individual operators to delay implementing ADS-B Out until others have developed the system, and avoid assuming a larger share of the cost of operating the NAS surveillance system. Direct financial incentives are appropriate to counteract these deficiencies, and encourage the development of ADS-B Out by accelerating the availability of its benefits. The ATA concurs with the ADS-B ARC that, some combination of financial incentives and operational benefits will be needed to significantly accelerate ADS-B equipage before the compliance date of the proposed rule. 10 The ARC Report also cites certain precedents for direct incentives, lists several financial methods and timing factors that should be considered. 11 The ATA emphasizes that it would be advantageous to make incentives for ADS-B implementation available as early as possible before the expected 2012 FAA reauthorization, and to provide incentives for in-service ADS-B demonstrations and evaluations. The ATA recommends that FAA develop financial incentives for airspace users to support a recommended two-phase program, accelerate implementation, and perform in-service demonstrations and evaluations. C. Establish a Two-Phase Implementation of ADS-B Out, and Accelerate the Availability of Benefits. The FAA over specified a costly system in the NPRM that needs to be tested before adoption in ATA s two phase approach adopts only those equipment and technical standards necessary to perform ADS-B out functions; broadcasting airplane information without interrogation by radar. In a first phase, the FAA should approve minimum technical standards for ADS-B Out position sensors and transponders that are consistent and compatible with the 10 ADS-B ARC Report, page ADS-B ARC Report, pages

11 standards of existing ADS-B systems (ie, TSO-C129a for position sensors, and RTCA DO-260 with a specified message element set for transponders). The FAA should then contract with the operators and facilitate necessary operational approvals so that an operator could perform initial ADS-B Out demonstrations and in-service evaluations at specific airports and geographic areas where operators could provide a critical mass of ADS-B equipped airplanes. This process would accelerate the availability and deployment of radar-like separation standards using ADS-B Out. As experience is gained, the process should be extended to validate advanced ADS-B Out procedures, including better-than-radar separation standards, and if indicated, final airworthiness standards for ADS-B Out. In the first phase, FAA also should coordinate with industry to commence research and development (R&D) simulation and modeling and in-service demonstrations and evaluations to validate advanced ADS-B In operational concepts and establish ADS-B In performance standards. In a second phase, the FAA should adopt performance standards for transponders and position sensor accuracy and integrity as necessary to perform the advanced ADS-B Out applications validated in Phase 1, and implement the advanced applications. Standards should be harmonized with international standards. The ATA recommends that FAA implement ADS-B Out in a two-phase program to accelerate the availability of benefits, adjust airworthiness standards commensurate with demonstration results, and establish ADS-B In procedural and airworthiness standards. D. ADS-B Deployment Requires Concurrent Development and Implementation Programs. The FAA Surveillance and Broadcast Services (SBS) office has acknowledged in the ADS-B ARC that concurrent development and implementation programs are needed. The SBS office also has recognized the vital importance of demonstrating the technology and providing some of the benefits of ADS-B to operators well before the proposed compliance deadline. To accomplish these objectives, the FAA would have to significantly alter the NPRM to include developing both ATC operating procedures and aircraft equipment. To do this, the FAA and industry should join in a unique, concurrent program of ADS-B Out demonstrations, in-service evaluations, compliance, and R&D to develop advanced ADS-B In standards, and build confidence in the ADS-B program. The program should address several uncertainties and risks that exist, including the following: No aircraft has been fully certificated to the proposed technical standards. Certain aspects of the proposed aircraft equipage appear to be based on a presumption of the results that a development program would yield, including requirements for ADS-B In, and are over specified and unnecessary for accelerating the start of a development process. 8

12 Upgrades to ATC standards and procedures to provide radar-like separation with ADS-B and other ADS-B applications, which are in an early stage of development, and typically take time to establish and implement. Key incentives for operators to implement the proposed ADS-B Out system are the potential benefits of the follow-on ADS-B In system that it would enable. However, operational applications, technical standards, costs and benefits for ADS-B In have not been defined. These require R&D and definition early in the two-phase program in order to proceed. In view of the program s uncertainties and risks, many of the recommendations in this section describe components of effective, concurrent in-service demonstration, evaluation and implementation programs. This unique approach is warranted in order to realize as soon as possible the efficiency benefits of ADS-B. 12 The ATA supports the plans of the SBS office insofar as they may support a concurrent, two-phase approach, and the realization of accelerated benefits for operators. With respect to programmatic factors, the ATA respectfully submits the following comments and recommendations: 1. FAA Should Formally Commit to Dates for the Availability of ADS-B Out Operational Applications. The preamble of the proposal describes a contract by which FAA will install the ground infrastructure component of ADS-B, and states that the infrastructure is scheduled to be available where current surveillance exists by the end of fiscal year However, the contract schedule does not commit the FAA to implement, by specific dates, the ATC standards and procedures necessary for demonstrations, inservice evaluations or operations that provide user benefits. In order to support these operations, including an accelerated accrual of benefits, the FAA should establish in conjunction with this rulemaking an accelerated schedule for the availability of traffic control services for ADS-B Out equipped airplanes that provides radar-like traffic separation, schedules expansions of those services to areas currently having no or limited radar coverage, and that schedules the availability of ATC services providing better-than-radar traffic separation. The FAA should commit to the schedule in the Rule. ATA recommends that FAA amend the proposed Part 91 language to state dates by which ADS-B Out applications will be available for evaluations and use. 12 The unique approach should accept a potential need for a regulatory amendment before the proposed compliance deadline based on system performance and in-service evaluation findings regarding benefit Fed. Reg. 193, page

13 2. The FAA Should Approve Initial Standards Harmonized with Existing ADS-B Operations. The ARC Report describes a relatively high level of equipage with ADS-B-capable transponders among US-registered aircraft. 14 With respect to accelerating the implementation of ADS-B Out and in-service development efforts, the status of position sensor systems and system integration and performance may be more pertinent than the status of the transponder component, and no aircraft system has been certificated to all of the standards and requirements proposed for ADS-B Out. The number of aircraft having position sensors, transponders, and overall system performance that approach full compliance with the proposed standards is insufficient to support early and effective demonstrations and evaluations of that configuration. Further, some of the proposed technical standards and requirements clearly are intended for the ADS-B In system, which has not been technically defined, and others should not have been set before gaining operational experience with ADS-B Out. As discussed in Section VI.A.2., the effective requirement for WAAS, for example, is unnecessary for initial demonstrations, evaluations, and operations, and WAAS is not used by other nations for their ADS-B systems. The proposed standards also would unnecessarily exceed the standards of Australia, Canada and Europe, which are based on TSO-C129a for position sensors and DO-260 for transponders. The FAA should coordinate with industry, including operators and manufacturers, to establish initial performance standards for ADS-B Out transponders and position sensors that are compatible and consistent with existing and imminent ADS-B Out operations in these countries, and cite the technical standards and message element sets that would meet those requirements. Minimum standards should be consistent with the initial operations projected for ADS-B Out, not a future, undefined system. Business cases for provisioning for future upgrades should be considered, but standards projected to provision for ADS-B In or RNP should not be mandated at this time. The ATA recommends that FAA coordinate with industry to establish initial technical standards that are compatible and consistent with Australian, Canadian and European standards (ie, TSO-C129a for position sensors and RTCA DO-260, with a specified message element set for transponders) for use in Phase ADS-B ARC Report, pages 14, 42, and Appendix C. 10

14 3. The FAA Should Perform Advanced R&D to Establish ADS-B In Standards by Key incentives for operators to support ADS-B Out system are the potential benefits of the follow-on ADS-B In system that it would enable. However, operational applications and technical standards for ADS-B In have not been defined, nor have its potential benefits been conclusively quantified. In order to gather and sustain the support of airspace users for ADS-B Out, ATA believes that ADS-B In must be defined early in the Phase 1 program. The ADS-B ARC recommended that FAA establish, by 2010, certification requirements for ADS-B In applications. 15 We agree. Further, the ATA adds that validating those requirements in coordination with the associated traffic separation standards and operational applications and benefits would require advanced R&D simulation and modeling and in-service demonstrations and evaluations. The ATA recommends that FAA coordinate with industry to perform R&D simulation and modeling to validate advanced ADS-B In operational applications, associated separation standards, and user benefits, and establish ADS-B In performance standards by E. FAA Should Better Coordinate with JPDO for NextGen Initiatives. The proposed rule would not specifically commit FAA to any operational benefit for airspace users until after 2019, when all users would be equipped with ADS-B Out. The FAA indicates that the follow-on ADS-B In system would further improve operational benefits, but that users may not realize a positive return on their investments until other elements of NextGen are implemented. 16 The FAA leaves to future assessments any quantification of the benefits to airspace users of the other elements of NextGen. 17 Conversely, the FAA clearly would realize nearly all of its benefits by adopting the ADS-B Out proposal. The proposed rule would initiate a migration of more NAS surveillance equipment into aircraft, incrementally relieving the FAA of its requirement to operate and maintain some ground radars. The FAA would have less incentive to aggressively follow up with the aircraft capability that could provide operators with a positive return on their investments -- ADS-B In. In view of these circumstances, the ATA is concerned that FAA already has signed a contract to initiate the implementation of an ADS-B ground infrastructure, but has not developed operating applications or technical standards for ADS-B In, nor reasonably assessed the substantially greater potential impact on operators of ADS-B In. Further, the ATA is concerned that the proposal would move forward despite open 15 ADS-B ARC Report, pages xi and Reg Eval, page Reg Eval, pages

15 issues with navigation systems and international interoperability. Overall, the proposal illustrates certain individual NextGen initiatives that are difficult to support on a case-by-case basis without further FAA and industry research and development. The ATA recommends that FAA coordinate with the Joint Planning and Development Office (JPDO) to develop more comprehensive assessments and integrated plans for NextGen initiatives. F. Detailed Technical Requirements should be in Airworthiness Standards. The proposal would publish the detailed technical and performance requirements for ADS-B Out in a new appendix to the Part 91 general operating rules. The FAA employs the same regulatory methodology for flight data recorders (FDRs), which contributes to compliance issues. The detailed technical requirements for FDRs used in commercial air operations are established in appendices to Part 121, which applies to commercial operators. The ATA has stated in comments to several FDR NPRMs that, for transport category airplanes, detailed technical requirements should be published or repeated in the Part 25 airworthiness standards, and directly applied to manufactures and new-production aircraft. 18 Manufacturers are the prime integrators of aircraft systems, and regardless of the location of the technical requirements, set the standard for integrating systems for supplemental type certificate (STC) holders and operators. Manufacturers would be more invested in the rulemaking process if a proposal or rule applied directly to new production aircraft; the same holds true for compliance with a rule, once it is finalized. For example, a recently published NPRM revealed substantive misunderstandings between airplane manufacturers and FAA with respect to detailed technical requirements in longstanding operating rules that govern data filtering and latency in FDR systems. 19 Discussions with aircraft and avionics manufactures indicated uncertainty about the intent of, or need for, some of the detailed technical requirements proposed for ADS-B Out, such as the intent of the proposed latency limitations. These discussions also reaffirmed that ADS-B avionics manufacturers and STC holders rely on airplane manufacturers to develop architectures and standards for system integration. Amendments to FDR rules often are implemented by STCs in which airplane manufacturers may have a negative business interest. Airplane manufacturers are not engaged in STC processes, even though they are a stakeholder. The same landscape would apply to a Part 91 rule for ADS-B. The FDR operating rule methodology compounds other aspects of compliance. Since FDR operating rules do not apply to manufacturers, the FAA requires airplane manufacturers to implement enhancements to FDR systems on the production line through issue papers. This practice is not open to the public, can set precedents in later FDR rulemaking, and has 18 ATA Comments to Docket Number FAA , April 16, 2007, page 4. The ATA comments provide justification for adding flight data requirements to 14 CFR Part Fed. Reg. 220, page 66638, Filtered Flight Data proposed rule. 12

16 contributed to a wide range of in-service FDR configurations. Occasional amendments to FDR operating rules that are applied by date of airplane manufacture further expand the range of configurations, as do STCs, a number of which often implement the amendments. The expanding range of FDR configurations makes each new FDR proposal and rule progressively more difficult to assess and manage for FAA and industry. This proposal would employ the problematic FDR regulatory methodology to ADS-B Out, but unlike FDRs, ADS-B Out systems could directly affect flight safety. The FAA should reconsider using the FDR regulatory methodology, particularly in view of the wider range of STC holders and Part 91 operators who would support and maintain ADS-B Out systems. Amending airworthiness standards to include the detailed requirements proposed for ADS-B Out would increase awareness and participation by industry, and reduce the kinds of issues experienced with FDRs. The ATA recommends that FAA include the proposed Appendix H in airworthiness standards. VI. ATA RECOMMENDS CHANGES TO CERTAIN PROVISIONS OF THE PROPOSED OPERATING RULE A. Global Harmonization. 1. Other Nation Navigation Systems and Interoperability. The ATA is encouraged by FAA s efforts to harmonize the proposed requirements with other nations and international organizations, including Australia, Canada, EUROCONTROL and the International Civil Aviation Organization (ICAO). However, we are concerned that ICAO Standards and Recommended Practices (SARPs) for ADS-B Out are not fully developed as the FAA states in the NPRM. 20 The ATA questions whether the FAA has fully resolved any conflicts. If SARPs are not fully developed, the FAA should not rely on research to determine whether any provisions in the NPRM conflict with ICAO standards or intentions. Instead, the FAA should contact ICAO directly to confirm that there are no conflicts. In part, our concern stems from the ICAO documents FAA used to research current ICAO standards listed in footnote 30 of the NPRM. One ICAO reference is a document published in 2005, and another is an Approved draft to be published in In view of ADS-B developments since 2005 and uncertainty with the language of a document that was to be published in 2006, we trust FAA will maintain frequent and direct contact with ICAO concerning current ICAO standards for ADS-B Fed. Reg. 193, page

17 2. FAA Should Provide for Initial Position Sensor Standards in Lieu of WAAS. As discussed in section IV.C., the NPRM, in effect, prescribes GPS augmented by the Wide Area Augmentation System (WAAS) as the position sensor system for ADS- B. 21 The draft advisory circular (AC) associated with the NPRM takes the same position by, for example, citing a time to alert requirement currently met only by WAAS receivers. 22 The FAA stated the navigation positioning accuracy of NACp 9 projected for WAAS receivers may eventually prove necessary for ADS-B In applications, including certain surface applications; however, those applications and procedures have not been defined. Requiring that ADS-B Out position sensors meet the performance requirements of ADS-B In would be presumptive, and for reasons discussed in section VIII.B.1., a strong inhibitor to early implementation. An accuracy of NACp 7 may support the most beneficial operational applications possible with ADS-B Out, if not all, and may be achievable with TSO-C129a GPS systems, with or without Selected Availability. The European Organisation for Civil Aviation Equipment (EUROCAE) states that, Minimum requirements for ADS-B accuracy are NACp = 7 for 3 NM separation, and NACp = 6 for 5 NM separation, adding that actual GPS receiver performance typically exceeds these minimum requirements. 23 Many TSO-C129a systems are in service and have been used in Australian ADS-B operations. 24 FAA should coordinate with industry, including operators and manufacturers, to validate the position sensor performance necessary to perform in-service demonstrations and evaluations in an initial configuration, revise and publish technical standards that detail the necessary performance, and coordinate the ATC training necessary for surveillance and control facilitated by the initial configuration. A decision whether to subsequently implement WAAS should be based on Phase 1 evaluation results, the definition of ADS-B In, the outlook for GNSS systems, and any relevant considerations for Required Navigation Performance (RNP) Fed. Reg. 193, page See Draft AC No: 20 ADS-B Out The Installation of Automatic Dependent Surveillance Broadcast (ADS-B) Out Equipment for Operation in the National Airspace System (NAS), page Safety, Performance and Interoperability Requirements Document for ADS-B-NRA Application, The European Organisation for Civil Aviation Equipment (EUROCAE), ED-126 V1.0, December 2005, pg Fed. Reg. 193, page Advisory Circular indicates that certain RNP applications may require NACp >8. 14

18 3. FAA Should Advocate Changes to Certain National Policies for GPS. Position sensor system requirements pose the greatest potential impact of the ADS-B Out concept to operators. This circumstance is created by developments and uncertainties in US and foreign navigation systems. 26 With the deployment of each new GNSS, SBAS or GBAS navigation system applicable to ADS-B position reporting, operators would incur a risk of needing new, additional position sensor systems (ie, receivers) During transition phases, operators may also have to maintain backwards-compatible receivers. Further, to assure operational reliability, two or three receivers may be needed for each new navigation system. Depending on the characteristics of installed receivers, operators could implement new receivers through software or hardware modifications or replacements, and changes could require new antennas and associated structural fatigue evaluations, new system controls, and integration with installed flight management systems (FMS). These factors apply to the proposed ADS-B Out system, which would require GPS and WAAS receivers, and disincentivize operators to implement any new position sensor system that does not offer predictable and stable benefits, economy, and interoperability. Moving more surveillance equipment (ie, ADS-B avionics) into the aircraft could result in costly, recurring position sensor system additions or modifications in response to changes in US navigation systems, and for international operations, changes in the navigation systems of other nations. We note Boeing and Lockheed are competing for a contract to replace the existing GPS constellation with Block III satellites beginning in Block III satellites will feature dual frequencies, and offer improved performance and global availability for users of ADS-B and many other applications. 28 When the constellation is fully operational, its performance could render WAAS cost-ineffective. However, the constellation may not be complete until well after the compliance deadline proposed for ADS-B Out. We also note the European Space Agency Galileo constellation is slated for completion in The US and the European Union have agreed to make the 26 Navigation systems refers to global navigation satellite systems (GNSS) such as GPS, satellite-based augmentation systems (SBAS) such as WAAS, ground-based augmentation systems (GBAS). These systems are used for precise navigation, and are envisioned as primary sources for position reporting for ADS-B surveillance. 27 GPS Constellations and Standards: Support for National Space Based Positioning Navigation and Timing (PNT) Advisory Committee, Richard Day, Vice President, En Route and Oceanic Services, FAA ATO-E, October 5, RNP standards are addressed in FAA Order and Advisory Circular AC , but may need further harmonization with ICAO, including harmonization to address SBAS and GBAS systems. 29 European Space Agency Web site, ( ). 15

19 Galileo Open Service and the Block IIIA GPS civil signal interoperable, 30 which could improve the performance and accelerate the availability of a mutuallycompatible US/EU GNSS. However, interoperability between Galileo and Block III GPS has not been demonstrated and may not extend to the SBAS or GBAS systems that would augment the respective GNSS systems. The GNSS horizon also includes Russia s GLONASS and the possibility of a Chinese system. In view of the outlook for national and international navigation systems and the dependency of air commerce on these systems, the ATA recommends that FAA: Advocate, early in Phase 1, a national policy requirement for a minimum constellation of 27 satellites in order to assure adequate and enduring signal availability and integrity. Advocate a national policy for accelerating the deployment of the dualfrequency GPS constellation and provision of a defined schedule of the deployment. Aggressively pursue international interoperability among SBAS or GBAS systems that augment various GNSS. Ensure that certification standards fully accommodate position sensor systems that will use planned GNSS constellations, including systems augmented by inertial reference units to avoid any lapse in satellite signal integrity B. Certain Actions are Necessary to Accelerate the Availability of ADS-B Benefits. All of the benefits of ADS-B to airspace users would stem from greater efficiencies in flight operations. As discussed in Section VIII, the proposed rule would not specifically commit FAA to any benefit for airspace users until after This section addresses specific elements of the two-phase ADS-B implementation program in order to accelerate the availability of benefits to airspace users well before 2020, and gather operational information and the support of users for the program. 1. Commit to the Continuous Availability and Expansion of Radar-Like Traffic Separation Standards. Operators expect that radar-like traffic separation will be maintained as the ADS-B ground infrastructure and services are added, and will be expanded to new areas where radar coverage currently is limited or unavailable. Enroute separation is of particular interest. The ARC Report indicates that enroute separation likely would be 30 European Union press release, July 27, 2007, ( ). 16

20 the soonest available and most beneficial operation, 31 and that expansion to areas where no [radar] coverage exists today would provide the most relative value and safety increases. 32 The FAA should commit in the Rule to the continuous availability of radar-like traffic separation standards and expansion of covered areas as ADS-B is deployed. 2. Approve the Most Beneficial Initial Operations by The ATA concurs with the ADS-B ARC that the FAA and the aviation community should identify the level of demand for specific operations and prioritize the availability of operations employing reduced separation standards. 33 The ARC Report lays groundwork for the prioritization process, and Phase 1 of the recommended two-phase program is intended to facilitate the prioritization, and the ATA stands ready to assist in the ARC process. The FAA should coordinate with industry to accelerate the identification and prioritization of operations enabled by ADS-B that, with approval of reduced separation standards, could provide a high level of user benefits by Action is Needed to Support ADS-B Operations in the Gulf of Mexico. The ATA concurs with the ADS-B ARC that the FAA should deploy an ADS-B infrastructure south of the Gulf of Mexico in order to accommodate ADS-B-equipped traffic that, as recommended in section VI.B.1., above, would be separated according to radar-like separation standards. 34 This action should be included in a published FAA plan for the ground infrastructure, and should be taken as early as possible. Of note, this action emphasizes the need for conclusive international interoperability. The FAA should ensure the early availability of an ADS-B infrastructure south of the Gulf of Mexico. 4. Determine by 2010 which Non-ADS-B Avionics Could be Replaced by ADS-B Equipage. Implementation of ADS-B may offer rare opportunities to reduce certain aircraft equipment. As discussed in the ARC Report, ADS-B message elements and requirements share a significant overlap with existing equipage. 35 Natural 31 ADS-B ARC Report, page ADS-B ARC Report, page ADS-B ARC Report, page ADS-B ARC Report, page ADS-B ARC Report, page ADS-B ARC Report, page

21 candidates for consolidation include Mode A and C transponders, emergency locator transmitters (ELTs), and TCAS. Phase 1 of the recommended two-phase program would offer an excellent opportunity to assess equipment consolidations. Identified equipment could be developed later in Phase 1 for potential integration with any Phase 2 upgrade of ADS-B equipage. Although the FAA states that the Conflict Detection function of ADS-B In is not intended to replace TCAS, 36 the ATA recommends deferring this determination until Phase 1 has been completed. Consistent with the ADS-B ARC, the ATA believes operators would have an increased incentive to equip if ADS-B provides an opportunity to remove avionics equipment. An assessment to identify such equipment should be performed early during the process. The ATA recommends that FAA collaborate with the aviation industry to determine by 2010 which non-ads-b avionics can be replaced by ADS-B equipage. 5. Establish Preferred Routes for ADS-B-equipped Airplanes. The ATA generally concurs with the ADS-B ARC that FAA should coordinate with operators to determine which new and existing routes, including routes in existing surveillance areas, could be employed to maximum benefit. 37 Consideration for routes over the Gulf of Mexico is of particular importance, as discussed in Section VI.B.1., above. Preferred routes should be made available incrementally, in the order of their potential benefit to evaluations and operations and coincident with the deployment of ADS-B ground infrastructure. The availability of the routes should be published, and any practice regarding access should be carefully vetted with operators. The ATA recommends that FAA coordinate with operators to establish preferred routes for ADS-B-equipped airplanes. 6. FAA Has Released an ADS-B Out Economic Decision Tool for Operators. The ADS-B ARC recommended that FAA develop a tool for operators to assess the direct benefits and costs of: (1) equipping early and (2) for operations after ADS-B Out equipage is required. 38 This tool would allow an operator to evaluate early ADS- B equipage on a NAS-wide basis, or localized for certain operations and airports. Some ATA members had a limited opportunity to provide inputs to its development. Airplane direct equipage costs were viewed as more of a key data input to the tool than a tool product, and direct costs for various categories of large commercial Fed. Reg. 193, page ADS-B ARC Report, page ADS-B ARC Report, page

22 transports were the subject of the ATA analyses discussed in Section VIII., below, and Appendix B. FAA recently released the tool, but not in time to assess its performance or products, or contribute to the development of these comments. 7. Establish Agreements with Operators For Demonstrations. The FAA should coordinate with operators and deploy, on an accelerated basis, ADS-B and services at air transport hubs and geographic areas where a group of operators would provide a level of ADS-B-equipped traffic meaningful to Phase 1 demonstrations and evaluations. The FAA should share operator equipage costs and provide approvals of operational procedures. In addition to commencing an in-service evaluation process, this measure would incentivize other users to equip early. ATA could help facilitate this process. C. Industry Requests Additional Information on Proposed Preflight Actions. The preamble of the proposal states that, In accordance with proper preflight actions, each operator would have to verify ADS-B Out availability for the flight planned route through the appropriate flight planning information sources. If the aircraft cannot meet the proposed performance requirements using a given position service, the operator would have to use either a different, available position service, re-route, or reschedule the flight. Under this proposal, pilot procedures are expected to be minimal. 39 Further detail is not provided and no corresponding provision appears in the proposed Part 91 language. We assume that the statement may be related to guidance in AC , which provides that operators must establish procedures for using a predictive performance capability for the navigation sensor that will be used in a RNP approach. 40 The capability may reside in the navigation system, such as a TSO-C129 GPS Class A1 sensor, or the operator s ground dispatch facility. The preamble statement could be interpreted to mean that the flight crew or dispatch must, prior to each flight, predict the performance of the navigation system along the entire flight plan route with respect to the accuracy and integrity requirements in proposed Appendix H. We believe this interpretation would be time consuming, untenable and unnecessary. The risk that the predictive checks are intended to mitigate predominantly stems from the GNSS service that is in use, provided that the navigation system has passed its preflight functional checks. Because this provision is not included in the rule text and is unclear, the ATA recommends that FAA provide industry, through the ADS-B ARC, with the specific intent and justification for the preamble statement on preflight actions before including it in an ADS-B Out final rule Fed. Reg. 193, page Advisory Circular , December 15, 2005, Appendix 4, page 1. 19

23 D. Evaluate the Potential Surface Safety Enhancements of ADS-B Out. In addition to improving the accuracy, timeliness and precision of control for airborne traffic, ADS-B Out also has a capability to enhance safety where the control tower and ground control are equipped with ADS-B surveillance displays. Although ADS-B In is envisioned to provide Airport Surface Situational Awareness by displaying traffic movements to flight crews, ADS- B Out could improve the situational awareness of controllers, allowing them to better alert flight crews to anticipated surface conflicts or developing hazards, particularly when obstacles, visibility, or darkness are factors. This capability could include coverage of various ground traffic and support equipment equipped with ADS-B transmitters and information available on ASDE-X. In-service evaluations may define safety enhancement opportunities such as improved alerting for controllers to taxi route deviations or developing or existing runway incursions. The ADS-B ARC Report cites a 2016 accrual date for ADS-B Out surface management and surface safety functions. 41 The ATA believes that date could be accelerated. The ATA recommends that FAA evaluate the potential of ADS-B Out to enhance surface management and safety during Phase 1 demonstrations and evaluations. VII. COMMENTS REGARDING TECHNICAL FACTORS ATA positions and recommendations regarding technical aspects of the proposed airplane equipage are embodied in preceding sections of these comments. The following provide additional, more specific comments and recommendations. A. Identify Existing Position Sources and Transponders Capable of Achieving Benefits Early. As discussed in section V.D.2., the FAA should coordinate with industry, including operators and manufacturers, to establish initial performance and technical standards for ADS-B Out transponders, position sensors and the overall system that are compatible and consistent with existing and imminent ADS-B Out operations (ie, TSO-C129a for position sensors and RTCA DO-260, with a specified message element set for transponders). Further, as discussed in section V. F., liaison with aircraft and avionics manufactures have indicated uncertainties about the intent of, or need for, some of the minimum broadcast message elements and other technical requirements proposed for ADS-B Out systems. Some of the proposed message element requirements have not been required by other civil aviation authorities to achieve radar-like traffic separation standards. Some may be appropriate for ADS-B In but would impede the acceleration of 41 ADS-B ARC Report, pages 19 to

24 an ADS-B Out program, and some are of questionable value. The recommended FAAindustry group should resolve these issues and establish standards for an initial, alternative ADS-B Out system. The ADS-B ARC Report provides a comparison of the message elements specified in DO-260 and DO-260A, Change Draft Advisory Circular (AC) 20-ADS-B provides guidance regarding at least one message element specified solely in the NPRM and a number of message elements in the DO-260 documents. The AC was published three months of the comment period opened and industry has not reached consensus on an appropriate message element set. Further, the majority of 45 requests for clarification submitted to FAA by the ADS-B ARC relate to message element set requirements, and the majority of FAA responses were that the request, may be submitted as a comment to the docket. 43 Appendix A lists message elements as depicted in the reference documents to illustrate sources and differences in content or terminology, and identify message elements under question. Given the concerns over message element set, the recommended FAA-industry group could use the Appendix as a tool to expedite establishing initial performance and technical standards for ADS-B Out transponders, position sensors and the integrated system and address the requests for clarification. The ATA recommends that an FAA-industry group refer to the Appendix and identify existing position sources and transponders capable of achieving early ADS-B Out benefits. B. Multilateration Should Augment ADS-B for Surface Applications. The ATA considered multilateration as an alternative to ADS-B Out. Primarily in view of the system s relatively limited ability to reduce traffic separation standards, particularly in non-radar environments, the ATA does not consider multilateration as a viable alternative to ADS-B. However, multilateration could provide the highly accurate position reports needed for surface applications removing one of the reasons cited for requiring a position sensor accuracy of NACp 9 and WAAS. Multilateration should augment ADS-B and should be re-evaluated after dual-frequency satellites and ADS-B In are implemented. 42 ADS-B ARC Report, page C Docket Document ID numbers FAA , December 19, 2007, and FAA , February 1, 2008, contain requests for clarification submitted to the FAA by the ADS-B ARC, and FAA responses. 21

25 VIII. COMMENTS REGARDING ECONOMIC VALUE AND IMPACT In its Executive Order analysis, the FAA asserted that the proposal is based on a reasoned determination that its benefits would justify its costs. The FAA relies on the anticipated benefits of ADS-B In and NextGen, which ADS-B Out would enable. ADS-B In benefits are speculative and NextGen benefits currently are unquantified. The Regulatory Evaluation is forthright in explaining that the costs of ADS-B Out could exceed its benefits for airspace users. 44 The FAA estimates that the costs and benefits of ADS-B Out to FAA would be relatively low and welldefined whereas the costs to airspace users would be relatively high. The potential benefits to users are explained in the Regulatory Evaluation, which cites FAA s intention for ADS-B Out to, enable improved Surveillance Services. 45 The Regulatory Evaluation assesses modest user benefits for phasing in: a limited capacity increase over the Gulf of Mexico starting in 2014; more efficient en route conflict detection probes starting in 2017; and more efficient continuous decent approaches (CDAs) starting at an unspecified date. 46 No other user benefits are identified for the period before 2020, and benefits through 2035 barely exceed FAA s mid-point estimate of ADS-B Out costs. More importantly, nothing in the regulatory language obligates the FAA to revise and implement ATC standards and procedures and provide ADS-B-enabled services (benefits) by certain dates before 2020, nor does the regulatory language require a reduction of traffic separation standards until after The Regulatory Evaluation also discusses uncertainties and dependencies applicable to the benefits of ADS-B Out, but as proposed, the actual benefit to airspace users would not be determined until after 2019 when all airspace users were equipped with ADS-B Out. The recommendations in these comments are intended to mitigate this uncertainty by maximizing opportunities to achieve benefits ADS-B Out may offer while minimizing costs. In view of the uncertain and dependent nature of the benefits of ADS-B Out, ATA focused efforts on assessing the impact component of the proposal. A. ATA Performed an Analysis of the Impact of Retrofitting Large Commercial Transports. For impact estimating purposes, the Regulatory Evaluation placed all large category (ie, over 12,500-pounds maximum takeoff gross weight) turbojets in one category. 47 This grouping did not provide information useful for assessing or validating the assumptions, methods, or system architecture groupings used, or the impact estimates. In order to develop credible estimates for fleet planning and comments to this proposal, the ATA conducted surveys of member airlines and manufactures to determine the airplane 44 Reg Eval, page Reg Eval, page Reg Eval, pages 52, 56 and Reg Eval, page

26 modifications that the proposed rule would require. Subsequently ATA surveyed members to estimate the impact of the modifications on the large commercial transport models that ATA members operate. The overall goal was to establish estimates for retrofitting airplanes of the types operated by ATA members by model, or by another category that would support meaningful fleet assessments, planning and comments. The overall analysis closely followed a methodology used by MITRE Corporation to produce a report on installing an early design of an ADS-B Out system. 48 The MITRE Report provided a useful example and assessment of a system similar to the alternative, initial system proposed in these comments. The Report also contained data that served as the basis for a forecast of the ATA fleet through The products of the ATA analysis are provided in Appendix B, with highlights below. B. The Impact of Retrofitting ADS-B Out is Twice FAA Estimates. The Regulatory Evaluation assessed only three categories of aircraft: general aviation, turboprop; and turbojet, with the latter applying to large commercial transports. The MITRE Report categorized large commercial transports as Classic, Neo Classic, and Modern to account for the range of relevant avionics architectures in these airplanes, and the ATA analysis was based on this methodology. The MITRE Report assessed an ADS-B Out system that would meet the technical requirements of TSO-C129a for GPS receivers (ie, non-waas) and DO-260 for ADS-B Out transponders. This configuration is similar to the initial system assessed in the ATA survey for use in Phase 1 except that MITRE assessed an airplane system having one TSO-C129a position sensor whereas ATA assessed systems having two or three sensors according to operator discretion. Of note, the FAA estimate also assumed one ADS-B sensor system per airplane. 49 The ATA survey also assessed the NPRM-proposed system, again assuming at least two compliant sensor systems. (See discussion below and in section VI.A.3 why two sensors was used). The following table cites includes estimates from the Regulatory Evaluation, MITRE Report, and ATA survey. 48 See MITRE Technical Report, A Predictive Model of User Equipage Costs for Future Air Traffic Services and Capabilities: An ADS-B Example, Kent V. Hollinger, P.E., James D. Nickum, P.E., Doyle T. Peed, Todd M. Stock, May 2006, Docket Document ID number FAA Reg Eval page

27 Retrofit Estimates Per-Airplane (Parts, Labor, Certification and Spares; 2007$) FAA Evaluation MITRE ATA Survey ATA Survey NPRM System Report System NPRM System Initial System Position Source TSO-C145a TSO-C129 TSO-C145a ADS-B Link NPRM + DO-260A DO-260 NPRM + DO-260A TSO-C129; SA Off DO-260 Average $69,600 $111,500 $157,500 $77,800 Notes: Except for the FAA cost figure, the table figures are averages across a forecast of the ATA fleet in The Regulatory Evaluation provides only high- and low-end estimates for turbojets (ie, $135,736 and $3,862 respectively). 50 The figure listed above for FAA is a mid-point that was calculated in direct proportion to the Regulatory Evaluation s U.S. inventory of turbojets and its aggregate impact estimate for that inventory. 51 The MITRE figure above is updated from 2004 dollars used in the MITRE Report to 2007 dollars. 1. Position Sensors May Have the Most Significant and Enduring Impact. As discussed in Section VI.A.3., position sensor systems could be the dominant impact factor in the ADS-B concept. Due to the need for dispatch reliability, operators would install or upgrade, as necessary, two or three position sensor systems, including any necessary antenna replacements or additions, to accommodate any new GNSS, SBAS or GBAS system required by regulation or operations. This upgrade applies to the proposed GPS system augmented by WAAS, and could apply to any future change to satellite-based navigation systems or respective augmenting systems, illustrating the value to U.S. and foreign operators of international interoperability. ATA survey results for the NPRM-proposed system and the MITRE estimate for the system it studied are more expensive than FAA s mid-point estimate. The survey estimate of the proposed system is over twice the FAA mid-point estimate and exceeds the FAA s high-point estimate. These differences are attributable to a lower than anticipated equipage with GPS upgradable to WAAS and upgradable 50 Reg Eval page Reg Eval page

28 transponders, particularly among Neo Classic and Modern category airplanes. The survey s estimate for the initial alternative system was lower than MITRE s even though the survey assumed that at least two position sensors would be required. This outcome is attributed to a higher than anticipated level of equipage with integrated or upgradable TSO-C129 GPS receivers, including Classic airplanes. The ATA survey illustrates the sensitivity of an ADS-B program to position sensor requirements, and indicates that mandating the proposed ADS-B Out system instead of an initial system based on TSO-C129 and DO-260 would more that double the impact among large transport operators. More importantly, survey results and MITRE Report suggest that the impact on users of ADS-B In could be over three times the impact of the proposed ADS-B Out system. 2. The Impact of Adding ADS-B In Would Surpass the Impact of ADS-B Out. Although the NPRM does not propose ADS-B In, a decision to commit to ADS-B Out should include consideration for the state of development of ADS-B In, which ADS-B Out would enable. Adding a Cockpit Display of Traffic Information (CDTI) to an airplane equipped with ADS-B Out would enable the ADS-B In system, and could be accomplished by integrating either a multi-function display (MFD) or an electronic flight bag (EFB). Consistent with findings discussed in the Regulatory Evaluation, any current estimate for retrofitting ADS-B In is speculative. The operating applications and supporting technical standards for ADS-B In/CDTI have not been defined. As an example, a determination of the most beneficial CDTI concept MFD or EFB has not been established. The ATA survey indicates that retrofitting either will have an impact several times greater than ADS-B Out, which is consistent with the outlook expressed in the Regulatory Evaluation. Both the ATA survey and the Regulatory Evaluation indicate that the per-airplane impact of integrating a MFD could be as high as one million dollars. This figure is speculative but shows that substantial research and development must be undertaken before investing too heavily in the ADS-B concept. They support the ATA recommendation to implement an initial ADS-B system in the first phase of a two-phase program, and suspend mandating the NPRM-proposed ADS-B Out system and its extensive provisioning for ADS-B In until the benefits of ADS-B Out and In are better understood. 25

29 IX. CONCLUSION Commercial transport operators certainly are interested in technology that could improve the capacity and efficiency of the NAS. ADS-B technology is the most promising foundation for NextGen and its goals of improving NAS performance while accommodating a three-fold growth in traffic. Our recommended program and actions can accelerate the implementation of ADS-B Out and instill confidence in an FAA-industry development program while avoiding premature and overly-optimistic commitments and investments. The ATA and its member airlines appreciate the opportunities we have had to contribute on the ASD-B ARC, and we certainly look forward to collaborating with FAA in the development of the ADS-B initiative. We sincerely appreciate the opportunity to provide comments on this rulemaking. Please let me know if you have any questions. Sincerely, AIR TRANSPORT ASSOCIATION OF AMERICA, INC. Basil J. Barimo Vice President, Operations & Safety 1301 Pennsylvania Avenue, NW Suite 1100 Washington, DC cc: Mr. Nicholas Sabatini, FAA, AVR-1 Mr. Vincent Capezzuto FAA, SBS PO Mr. John Hickey, FAA, AIR-1 Mr. James Ballough, FAA, AFS-1 26

30 APPENDIX A: Minimum Broadcast Message Element Set Table B-1

31 APPENDIX B: ATA Surveys, Fleet Forecast and Program Cost Estimates The main objective of the ATA survey was to provide member airlines with credible estimates for fleet planning and comments to this proposal in the absence of any earlier useable estimate of the NPRM-proposed ADS-B Out system, by airplane model or category. This objective was met and per airplane estimates in this Appendix could be entered into the anticipated FAA economic tool discussed in sections VI and VII. The survey also addressed the initial alternative configuration of ADS-B Out, frequently referencing the MITRE Report for comparison, and ADS-B In. Of note, estimates for adding ADS-B In to an aircraft equipped ADS-B Out are highly speculative at this time, primarily due to the lack of technical definition for ADS-B In. Results to the ATA survey are provided in four sections described as follows: 1. Forecast Retrofit Schedule for ATA-Member Fleets Representative schedules, through 2019, of ADS-B Out of retrofits that would be required by the NPRM, including fleet costs to members for the proposed ADS-B Out system and the ATA initial alternative. The retrofit schedule is based on a fleet forecast in section 3, below. 2. Consolidated Results of Member Surveys Consolidated results of an ATA-member survey of the estimated costs of retrofitting ADS-B in three categories of large commercial transports. These are the same general categories assessed by MITRE (ie, Classics, Neo Classics, and Modern). Results for each category include estimates for three ADS-B Out systems the ATA initial alternative ( Modification 1, which is similar to the system assessed by MITRE), the ADS-B Out system proposed by the NPRM ( Modification 2 ), and ADS-B In ( Modification 3 ). Results also include one estimate provided for an ADS-B In system that employs an electronic flight bag in lieu of a multi-function display. 3. Fleet Forecast, by Model, for the ATA-Member Airline Fleet. A forecast of the fleet of airplane models operated by ATA-member airlines based on general growth rates for commercial transports derived from the MITRE Report, including retirements and accruals. Forecasts for certain classic and new-design models were adjusted to yield the overall growth rate. 4. ADS-B Out Retrofit Costs for a Forecasted ATA Fleet Estimates for retrofitting ADS-B into a forecast fleet of commercial transport models of ATA members. These fleet-wide estimates were made by applying MITRE's cost estimates to the system assessed by MITRE; and applying ATA survey results to the alternative ADS-B Out system (Modification 1) and to the system proposed by the NPRM (Modification 2); and ADS-B In (Modification 3). Fleet estimates for retrofit activities are provider for the end of CY 2015 and the end of CY B-1

32 B-2

33 B-3

34 B-4

35 B-5

36 B-6

37 B-7

38 B-8

39 B-9