99-17360. Reduced Vertical Separation Minimum  

  • [Federal Register Volume 64, Number 130 (Thursday, July 8, 1999)]
    [Proposed Rules]
    [Pages 37018-37024]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 99-17360]
    
    
    
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    Part V
    
    
    
    
    
    Department of Transportation
    
    
    
    
    
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    Federal Aviation Administration
    
    
    
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    14 CFR Part 91
    
    
    
    Reduced Vertical Separation Minimum;
    
    
    
    Proposed Rule
    
    Federal Register / Vol. 64, No. 130 / Thursday, July 8, 1999 / 
    Proposed Rules
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 91
    
    [Docket No. FAA-1999-5925; Notice No. 99-10]
    RIN 2120-AG82
    
    
    Reduced Vertical Separation Minimum
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Notice of proposed rulemaking (NPRM).
    
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    SUMMARY: The Federal Aviation Administration (FAA) intends by this 
    proposed rule to enable the implementation of Reduced Vertical 
    Separation Minimum (RVSM) in Pacific oceanic airspace. RVSM is the 
    reduction of the vertical separation of aircraft from 2,000 feet to 
    1,000 feet at flight levels (FLs) between FL 290 (29,000 feet) and FL 
    410 (41,000 feet). RVSM is applied only between aircraft that meet 
    stringent altimeter and auto-pilot performance requirements. RVSM is 
    currently applied only in North Atlantic (NAT) Minimum Navigation 
    Performance Specification (MNPS) airspace. The introduction of RVSM in 
    Pacific oceanic airspace would make more fuel and time efficient flight 
    levels and tracks available to operators and would enhance airspace 
    capacity. Since March 1997 in the North Atlantic, RVSM has been shown 
    to maintain an acceptable level of safety. International RVSM planning 
    groups have agreed to implement RVSM on or before February 24, 2000.
    
    DATES: Comments must be submitted on or before September 7, 1999.
    
    ADDRESSES: Comments on this NPRM should be delivered or mailed, in 
    triplicate, to: U.S. Department of Transportation Dockets, Docket No. 
    [FAA-1999-5925], 400 Seventh Street SW., Room Plaza 401, Washington, DC 
    20590. Comments must indicate the Docket Number. Comments also may be 
    submitted electronically to the following Internet address: 9-NPRM-
    [email protected] Comments may be examined in Room Plaza 401 weekdays 
    between 10:00 a.m. and 5:00 p.m. weekdays, except Federal holidays.
    
    FOR FURTHER INFORMATION CONTACT: Mr. Roy Grimes, AFS-400, Flight 
    Technologies and Procedures Division, Flight Standards Service, Federal 
    Aviation Administration, 600 Independence Avenue, SW., Washigton, DC 
    20591, telephone (202) 267-3734.
    
    SUPPLEMENTARY INFORMATION:
    
    Comments Invited
    
        This action is a product of international agreements under which 
    the international aviation community, including the United States, 
    plans to implement RVSM in Pacific airspace. The International Civil 
    Aviation Organization (ICAO) Asia/Pacific Air Navigation Planning and 
    Implementation Regional Group (APANPIRG), the Informal Pacific Air 
    Traffic Service Coordinating Group (IPACG), and the Informal South 
    Pacific Air Traffic Service Coordinating Group have concluded that 
    Pacific oceanic traffic will continue to increase significantly in the 
    next few years. To accommodate this increase in air traffic, these 
    groups have established a goal of implementing RVSM in Pacific Oceanic 
    airspace on or before February 24, 2000. Affected FIRs include 
    Anchorage Arctic, Anchorage Continental, Anchorage Oceanic, Auckland 
    Oceanic, Brisbane, Edmonton, Honiara, Los Angeles, Melbourne, Nadi, 
    Naha, Nauru, New Zealand, Oakland, Oakland Oceanic, Port Moresby, 
    Seattle, Tahiti, Tokyo, and Vancouver.
        Interested persons are invited to participate in this proposed 
    rulemaking by submitting such written data, views, or arguments, as 
    they may desire. Comments relating to the environmental, energy, 
    federalism, or economic impact that may result from adopting the 
    proposals in this notice are also invited. Comments that provide the 
    factual basis supporting the views and suggestions presented are 
    particularly helpful in developing reasoned regulatory decisions. 
    Comments should identify the regulatory docket number and be submitted 
    in triplicate to the above-specified address.
        Because this proposed rule was developed as a result of an 
    international agreement, comments deemed substantive will be presented 
    for consideration and reviewed by the international community under the 
    auspices of ICAO. If considered salient, the comments will be included 
    for use by all participating member States.
        All comments received will be available both before and after the 
    closing date for comments in the Department of Transportation Docket 
    for examination by interested persons.
        The FAA will acknowledge receipt of a comment if the commenter 
    includes a self-addressed, stamped postcard on which the following 
    statement is made: ``Comments to Docket No. FAA-1999-5925.'' The FAA 
    will date, time stamp, and return the postcard.
    
    Availability of This Document
    
        Any person may obtain a copy of this document by submitting a 
    request to the Federal Aviation Administration, Office of Rulemaking, 
    ARM-1, 800 Independence Avenue, SW., Washington, DC 20591, or by 
    calling (202) 267-9677. Communications must identify the docket number 
    of this rule.
        Persons interested in being placed on the mailing list for future 
    rulemaking actions should request from the above office a copy of 
    Advisory Circular No. 11-2A, Notice of Proposed Rulemaking Distribution 
    System, that describes the application procedure.
        An electronic copy of this document may be downloaded, using a 
    modem and suitable communications software, from the FAA regulations 
    section of the Fedworld electronic bulletin board service (telephone 
    703-321-3339), the Federal Register's electronic bulletin board service 
    (telephone: 202-512-1661), or the FAA's Aviation Rulemaking Advisory 
    Committee Bulletin Board Service (800-322-2722 or 202-267-5948).
        Internet users may reach the FAA's web page at http://www.faa.gov 
    or the Federal Register's Web page at http://www.access.gpo.gov/
    su__docs for access to recently published rulemaking documents.
    
    Background
    
    Statement of the Problem
    
        Air traffic on Pacific routes between the U.S. and Asia has 
    increased steadily in the past few years and is projected to continue 
    to increase. The North Pacific Track System (NOPAC) is the densest 
    oceanic traffic area in the Pacific. Between 1994 and 198, the annual 
    traffic count on the NOPAC increased from 42,305 to 60,772 flights 
    which represents an increase of 44 percent. The FAA Aviation Forecast 
    for Fiscal Years 1998-2010 estimates that transpacific passenger 
    traffic will continue to increase at 6.6 percent per year through 2010. 
    Studies conducted by independent aviation industry analysts forecast 
    the Pacific area to be the fastest growing area for flights to/from the 
    United States.
        Unless action is taken, as traffic increases, the opportunity for 
    aircraft to fly at fuel-efficient altitudes and tracks will be 
    significantly diminished. In addition, air traffic service providers 
    may not be able to accommodate greater numbers of aircraft in the 
    airspace without invoking restrictions that can result in traffic 
    delays and fuel penalties.
        With air traffic levels increasing annually worldwide, FAA airspace
    
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    planners and their international counterparts continually explore 
    methods of enhancing the air traffic control (ATC) system's ability to 
    accommodate traffic in a safe and efficient manner. NAT airspace was 
    chosen to be the first airspace for RVSM introduction because it is the 
    busiest oceanic airspace in the world and traffic is forecast to 
    continue to increase. The NAT Traffic Forecasting Group Report shows 
    that the number of annual flight operations increased 30 percent 
    between 1991 and 1996 with a forecast 67 percent rise over the 1992 
    level of 228,200 by 2002.
        Prior to the introduction of RVSM, 27 percent of flights in NAT 
    airspace were issued clearances on tracks and at altitudes other than 
    those requested by the operators in their filed flight plans. These 
    flights were, therefore, generally conducted at less than optimum 
    tracks and altitudes for the aircraft, resulting in time and fuel 
    inefficiencies.
        The North Atlantic Implementation Management Group has observed the 
    following improvements in NAT operations due to the introduction of 
    RVSM:
        1. 50 percent of the fuel penalty attributed to NAT system 
    operation was eliminated. (The total NAT system fuel penalty is 
    estimated based on track design, meteorological forecast, cruise level 
    and traffic congestion penalties).
        2. 25 percent fewer fixed tracks were required to be published. 
    (This allows more airspace for operators to fly preferred tracks).
        3. There was a 5 percent increase in flights cleared to fly both at 
    the altitude and on the track that the operator requested.
        RVSM alleviates the limitation on air traffic management at high 
    altitudes imposed by the conventional 2,000-foot vertical separation 
    standard. Below FL 290, air traffic controllers can assign aircraft 
    operating under Instrument Flight Rules (IFR) altitudes a minimum of 
    1,000 feet apart. Above FL 290, however, the Conventional Vertical 
    Separation Minimum (CVSM) is 2,000 feet.
    
        Note: Flight levels are stated in digits that represent hundreds 
    of feet. The term flight level is used to described a surface of 
    constant atmospheric pressure related to a reference datum of 29.92 
    inches of mercury. Rather than adjusting altimeters for changes in 
    atmospheric pressure, pilots base altitude readings above the 
    transition altitude [in the United States, 18,000 feet] on this 
    standard reference. FL 290 represents the pressure surface 
    equivalent of 29,000 feet based on the 29.29'' Hg datum; FL 310 
    represents 31,000 feet, and so on.)
    
        The 2,000-foot minimum vertical separation restricts the number of 
    flight levels available. Flight levels 310, 330, 350, 370, and 390 are 
    flight levels at which aircraft crossing oceanic airspace operate most 
    economically. At peak hours these FLS can become congested. When all 
    RVSM FLs are utilized, six additional flight levels are available: FLs 
    300, 320, 340, 360, 380, and 400. Increasing the number the FLs 
    available in the Pacific region is projected to achieve operator 
    benefits similar to those achieved in the NAT (i.e., mitigation of fuel 
    penalties attributed to the inability to fly optimum altitudes and 
    tracks). In the Pacific, RVSM is initially planned to be implemented 
    between FL 290 and FL 390 (inclusive). At this time, traffic density 
    above FL 390 does not warrant implementing RVSM at FL 400 and FL 410.
        Another factor that has led Pacific planners to believe that RVSM 
    implementation should be pursued aggressively is that a large 
    percentage of Pacific operators and aircraft have already received 
    approval to conduct RVSM operations. This is due to the fact that 
    Pacific operators conduct operations worldwide and therefore, have been 
    required to obtain RVSM approval to operate in NAT RVSM airspace. 
    Aircraft that have been approved for RVSM are approved for RVSM in any 
    area of the world where it is applied. The Pacific RVSM Implementation 
    Task Force (Task Force) has reviewed the RVSM approval status of 
    Pacific operators and aircraft and found that approximately 36 percent 
    of Pacific operations are already conducted by RVSM approved operators 
    and projected that this figure will grow to 56 percent in the near 
    term.
    
    History
    
        The ICAO APAN/PIRG develops and provides oversight for plans and 
    policy related to air navigation in the Pacific and Asia. The APAN/PIRG 
    established the Task Force to develop and implement RVSM policy and 
    programs in the Pacific. The Task Force is using the policy and 
    criteria developed in other ICAO forums to build the RVSM program for 
    the Pacific. The following reviews the RVSM program development in U.S. 
    and ICAO forums.
        Rising traffic volume and fuel costs, which made flight at fuel-
    efficient altitudes a priority for operators, sparked an interest in 
    the early 1970s in implementing RVSM above FL 290. In April 1973, the 
    Air Transport Association of America (ATA) petitioned the FAA for a 
    rule change to reduce the vertical separation minimum to 1,000 feet for 
    aircraft operating above FL 290. The petition was denied in 1977 in 
    part because (1) Aircraft altimeters has not been improved 
    sufficiently, (2) improved maintenance and operational standards has 
    not been developed, and (3) altitude correction was not available in 
    all aircraft. In addition, the cost of modifying nonconforming aircraft 
    was prohibitive. The FAA concluded that granting the ATA petition at 
    that time would have adversely affected safety. Nevertheless, the FAA 
    recognized the potential benefits of RVSM under certain circumstances 
    and continued to review technological developments, committing 
    extensive resources to studying aircraft altitude-keeping performance 
    and necessary criteria for safely reducing vertical separation above FL 
    290. These benefits and data showing that implementing RVSM is 
    technically feasible have been demonstrated in studies conducted 
    cooperatively in international forums, as well as separately by the 
    FAA.
        Because of the high standard of performance and equipment required 
    for RVSM, the FAA advocated initial introduction of RVSM in oceanic 
    airspace where special navigation performance standards were already 
    required. Special navigation areas require high levels of long-range 
    navigation precision due to the separation standard applied. RVSM 
    implementation in such airspace requires an increased level of 
    precision demanded of operators, aircraft, and vertical navigation 
    systems.
        On March 27, 1997, RVSM was implemented in one such special 
    navigation area of operation, the NAT MNPS, established in the ICAO NAT 
    Region. In designated NAT MNPS airspace, tracks are spaced 60 nautical 
    miles (NM) apart. Between Fs 310 and 390 (inclusive), aircraft are 
    separated vertically by 1000 feet. All aircraft operating in this 
    airspace must be appropriately equipped and capable of meeting required 
    lateral navigation performance standards of part 91, section 91.705 and 
    vertical navigation performance standards of part 91, section 91.706. 
    Operators must follow procedures that ensure the standards are met, and 
    flight crews are trained and qualified to meet the standards. Each 
    operator, aircraft, and navigation system combination must receive and 
    maintain authorization to operate in the NAT MNPS. The NATSPG Central 
    Monitoring Agency monitors NAT MNPS. The NATSPG Central Monitoring 
    Agency monitors NAT aircraft fleet performance to ensure that a safe 
    operating environment is maintained.
        FAA data indicate that the altitude-keeping performance of most 
    aircraft flying in oceanic airspace can meet the
    
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    standards for RVSM operations. The FAA and ICAO research to determine 
    the feasibility of implementing RVSM included the following four 
    efforts:
        1. FAA Vertical Studies Program. This program began in mid-1981, 
    with the objectives of collecting and analyzing data on aircraft 
    performance in maintaining assigned altitude, developing program 
    requirements to reduce vertical separation, and providing technical and 
    operational representation on the various working groups studying the 
    issue outside the FAA.
        2. RTCA Special Committee (SC)-150. RTCA, Inc., (formerly Radio 
    Technical Commission for Aeronautics) is an industry organization in 
    Washington, DC, that addresses aviation technical requirements and 
    concepts and produces recommended standards. When the FAA hosted a 
    public meeting in early 1982 on vertical separation, it was recommended 
    that RTCA be the forum for development of minimum system performance 
    standards for RVSM. RTCA SC-150 was formed in March 1982 to develop 
    minimum system performance requirements, identify required improvements 
    to aircraft equipment and changes to operational procedures, and assess 
    the impact of the requirements on the aviation community. SC-150 served 
    as the focal point for the study and development of RVSM criteria and 
    programs in the United States from 1982 to 1987, including analysis of 
    the results of the FAA Vertical Studies Program.
        3. ICAO Review of the General Concept of Separation Panel (RGCSP). 
    In 1987, the FAA concentrated its resources for the development of RVSM 
    programs in the ICAO RGCSP. The U.S. delegation to the ICAO RGCSP used 
    the material developed by SC-150 as the foundation for U.S. positions 
    and plans on RVSM criteria and programs. The Panel's major conclusions 
    were:
         RVSM is technically feasible without imposing unreasonably 
    demanding technical requirements on the equipment.
         RVSM provides significant benefits in terms of economy and 
    en route airspace capacity.
         Implementation of RVSM on either a regional or global 
    basis requires sound operational judgment supported by an assessment of 
    system performance based on: aircraft altitude-keeping capability, 
    operational considerations, systems performance monitoring, and risk 
    assessment.
        4. NATSPG and the NATSPG Vertical Separation Implementation Group 
    (VISG).
        The NATSPG Task Force was established in 1988 to identify the 
    requirements to be met by the future NAT Region Air traffic services 
    systems; to design the framework for the NAT airspace system concept; 
    and to prepare a general plan for the phased introduction of the 
    elements of the concept. The objective of this effort was to permit 
    significant increases in airspace capacity and improvement in flight 
    economy. At the meeting of the NATSPG in June 1991, all of the NAT air 
    traffic service provider States, as well as the International Air 
    Transport Association (IATA) and International Federation of Airline 
    Pilots Association (IFALPA), endorsed the Future NAT Air Traffic 
    Services System Concept Description developed by the NATSPG Task Force. 
    With regard to the implementation of RVSM, the Concept Description 
    concludes that priority must be given to implementation of this measure 
    as it is believed to be achievable within the early part of the concept 
    time frame. The NATSPG's initial goal was to implement RVSM between 
    1996 and 1997. To meet this goal, the NATSPG established the VSIG in 
    June 1991 to take the necessary actions to implement RVSM in the NAT. 
    These actions included:
         Programs and documents to approve aircraft and operators 
    for conducting flight in the RVSM environment and to address all issues 
    related to aircraft airworthiness, maintenance, and operations. The 
    group has produced guidance material for aircraft and operator approval 
    that ICAO has distributed to civil aviation authorities and NAT users. 
    Also, ICAO has planned that the guidance material be incorporated in 
    the approval process established by the States.
         Developing the system for monitoring aircraft altitude-
    keeping performance. This system is used to observe aircraft 
    performance in the vertical plane to determine that the approval 
    process is uniformly effective and that the RVSM airspace system is 
    safe.
         Evaluating and developing ATC procedures for RVSM, 
    conducting simulation studies to assess the effect or RVSM on ATC, and 
    developing documents to address ATC issues.
        The ICAO Limited NAT Regional Air Navigation Meeting held in 
    Portugal in November 1992 endorsed the NATSPG RVSM implementation 
    program. At the meeting, it was concluded that RVSM implementation 
    should be pursued. The FAA concurred with the conclusions of the NATSPG 
    on RVSM implementation.
    
    Reference Material
    
        The FAA and other entities studying the issues of RVSM requirements 
    have produced a number of studies and reports. The FAA used the 
    following documents in the development of this amendment:
         Summary Report of United States Studies on 1,000-Foot 
    Vertical Separation Above Flight Level 290 (FAA, July 1988).
         Initial Report on Minimum System Performance Standards for 
    1,000-Foot Vertical Separation Above Flight Level 290 (RTCA SC-150, 
    November 1984); the report provides information on the methodology for 
    evaluating safety, factors influencing vertical separation, and 
    strawman system performance standards.
         Minimum System Performance Standards for 1,000-Foot 
    Vertical Separation Above Flight Level 290 (Draft 7, RTCA, August 
    1990); the FAA concurred with the material developed by RTCA SC-150.
         The Report of RGCSP/6 (ICAO, Montreal, 28 November-15 
    December 1988) published in two volumes. Volume 1 summarizes the major 
    conclusions reached by the panel and the individual States. Volume 2 
    persents the complete RVSM study reports of the individual State:
         European Studies of Vertical Separation Above FL 290--
    Summary Report (prepared by the EUROCONTROL Vertical Studies Subgroup).
         Summary Report of United States Studies on 1,000-Foot 
    Vertical Separation Above Flight Level 290 (prepared by the FAA 
    Technical Center and ARINC Research Corporation).
         The Japanese Study on Vertical Separation.
         The Report of the Canadian Mode C Data Collection.
         The Results of Studies on the Reduction of Vertical 
    Separation Intervals for USSR Aircraft at Altitudes Above 8,100 m 
    (prepared by the USSR).
         Report of RGCSP/7 (Montreal, 30 October-20 November 1990) 
    containing a draft Manual on Implementation of a 300 M (1,000 Ft) 
    Vertical Separation Minimum (VSM) Between FL 290 and 410 Inclusive, 
    approved by the ICAO Air Navigation Commission in February 1991 and 
    published as ICAO Document 9574.
         Interim Guidance Material 91-RVSM, ``Approval of Aircraft 
    and Operators for Flight in Airspace Above FL 290 Where a 1,000 Foot 
    Vertical Separation is Applied'' (March 14, 1999). The interim guidance 
    continues to provide recommended procedural steps for obtaining FAA 
    approval.
    
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         AC No. 91-70, ``Oceanic Operations'' (September 6, 1994).
         Flight Standards Handbook Bulletin for Air Transportation 
    (HBAT) ``Approval of Aircraft and Operators for Flight in Airspace 
    Above Flight Level 290 Where a 1,000 Foot Vertical Separation Minimum 
    is Applied'' (HBAT 97-02).
         NATSPG Airspace Monitoring Sub-group Vertical Monitoring 
    Report. (Issued quarterly)
    
    Related Activity
    
        Projected increases in pacific oceanic air traffic and the 
    successful implementation of RVSM operations in the NAT support the 
    addition of RVSM in the Pacific. Pacific operators and Air Traffic 
    Service (ATS) providers have requested that RVSM be pursued 
    aggressively.
        The Pacific RVSM Implementation Task Force is the international 
    body that is developing Pacific RVSM implementation plans. The Task 
    Force is chaired by an FAA representative from the Air Traffic 
    International Staff and supported by an ICAO representative from the 
    Asia/Pacific Regional Office. The Task Force has three standing sub-
    groups: the Air Traffic Operations Group, the Aircraft Operations and 
    Airworthiness Group and the Safety and Monitoring Group. The working 
    groups are chaired by FAA air traffic and flight standards specialists. 
    The Task Force includes representatives from Asia and Pacific civil 
    aviation authorities, operators and the pilot and air traffic 
    controller associations. The Task Force meets at approximately 
    quarterly intervals to develop policy and procedure documents and to 
    progress implementation tasks.
        The Task Force chairperson and the three sub-group chairpersons 
    will oversee the two phases of the Pacific implementation process:
    
    System Verification Phase
    
        During the verification phase, aircraft will continue to be 
    separated vertically by 2,000 feet. Operators and aircraft that have 
    not already been approved for RVSM will begin to receive RVSM approval 
    in accordance with part 91, section 91.706 and Appendix G (or their 
    equivalent for foreign operators). The overall objectives of the system 
    verification phase are to:
        1. Confirm that the target level of safety (TLS) will continue to 
    be met.
        2. Confirm that aircraft approved for RVSM operation demonstrate 
    altitude-keeping performance that meets RVSM standards. This will be 
    achieved by:
         Identifying and eliminating any causes of out-of-tolerance 
    altitude-keeping performance, in general or for specific aircraft 
    groups; and
         Monitoring a sample of RVMS-approved aircraft and 
    operators that is representative of the total Pacific population.
        3. Verify that operational procedures adopted for RVSM are 
    effective and appropriate.
        4. Confirm that the altitude-monitoring program is effective. The 
    principal purpose of this phase has been to gain confidence that the 
    operational trial phase can begin.
    
    Initial Operational Capability/System Monitoring Phase
    
        When the objectives of the system verification phase have been met, 
    RVSM will be implemented at designated flight levels. The first year 
    after implementation is considered the operational trials phase. The 
    objectives of the operational trial phase are to:
        1. Continue to collect altitude-keeping performance data.
        2. Increase the level of confidence that safety goals are being 
    met.
        3. Demonstrate operationally that there are no difficulties with 
    RVSM implementation.
        Beginning February 24, 2000, only RVSM compliant aircraft will be 
    cleared to operate in the major Pacific FIRs between FLs 290 and 390 
    (inclusive). Aircraft that are not RVSM compliant (e.g., State 
    aircraft, ferry and maintenance flights) will only be cleared to 
    operate between FLs 290 and 390 (inclusive), traffic permitting, after 
    prior coordination with the appropriate oceanic center. 2,000-foot 
    vertical separation will be applied to such aircraft.
        Provided that all requirements continue to be met, at the end of 
    one year, RVSM will be declared fully operational.
    
    Altitude-Keeping Performance
    
        For the past three years, the FAA, in conjunction with the NATSPG, 
    has monitored aircraft altitude-keeping performance of RVSM approved 
    aircraft. A major objective of monitoring is to establish that the 
    altitude-keeping performance of the aircraft fleet operating in 
    airspace where RVSM is applied continues to meet minimum requirements.
        Altimeter system error (ASE) is the major component of aircraft 
    altitude-keeping performance. In the past three years, 36,000 
    measurements of altimetry system error have been taken for over 3,000 
    different airframes. Those measurements have shown that the altitude-
    keeping performance of aircraft approved for RVSM operations is 
    significantly better than the minimum requirement. The ASE requirement 
    established for RVSM is that average ASE not exceed 80 feet and 99.9% 
    of ASE observed not exceed 245 feet. The monitoring results have shown 
    that actual average ASE is -4 feet and 99.9% of ASE is within 156 feet.
        The FAA has determined that the appropriate method of assessing 
    collision risk is the Reich collision risk model (CRM). As noted in AC 
    No. 91-70, Oceanic Operations, collision risk refers to the number of 
    midair accidents likely to occur due to the loss of separation in a 
    prescribed volume of airspace for a specific number of flight hours.
        Collision Risk Methodology (CRM) was used to develop the 
    requirements for safe implementation of a 1,000-foot vertical 
    separation standard. The United States supported the methodology used 
    to derive the accepted level of safety for RVSM implementation.
        The TLS that is being used in the North Atlantic and the Pacific 
    regions to assess safety is no more than five fatal accidents in 1 
    billion flying hours. The level of safety was developed using 
    historical data on safety from global sources. One precedent used was a 
    period of 100 to 150 years between midair collisions. When the TLS of 5 
    accidents in a billion flying hours is projected in terms of a calendar 
    year interval between accidents in the Pacific, it yields a theoretical 
    interval of approximately 322 years between midair collisions. The 
    accepted level of safety is consistent with the acceptable level for 
    aircraft hull loss and is based on the precedence of extremely 
    improbable events as they relate to system safety, the basis for 
    certain requirements in certification regulations such as 14 CFR 
    25.1309.
        To ensure that the TLS is met, the FAA is monitoring the total 
    vertical error (TVE) and the remaining CRM parameters that are critical 
    for safety assessment (probability of lateral and longitudinal 
    overlap). TVE is defined as the geometric difference between the 
    aircraft and the flight level altitude. To monitor TVE, the FAA has 
    deployed measurement systems that will produce estimates of aircraft 
    and flight level geometric altitude. The overall goal of monitoring is 
    to ensure that airworthiness, maintenance, and operational approval 
    requirements result in required system performance (and level of 
    safety) in the flight environment on a continuing basis. One such 
    measurement/monitoring system is a Global Positioning System (GPS)-
    
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    based monitoring system (GMS). The GMS has been used extensively in the 
    NAT along with ground based Height Monitoring Units (HMUs). Due to the 
    lack of land masses in the PAC, the GMS will be used for RVSM system 
    verification and monitoring.
        The on-going assessment of risk in the North Atlantic over the past 
    two years has shown that the TLS of 5 accidents in 1 billion flight 
    hours can be met. All sources of error related to aircraft performance 
    and to human error have been assessed. One major incident that was 
    observed in the on-going monitoring was judged to be a pilot error not 
    related to the introduction of RVSM. In this incident, an aircraft did 
    not fly the flight level to which it was cleared, but reported to ATC 
    that it was flying the cleared level. This incident was advertised to 
    the user community for emphasis in pilot training programs.
    
    Current Requirements
    
        Part 91 Section 91.706 (Operations within airspace designated as 
    Reduced Vertical Separation Minimum Airspace.) and Appendix G to Part 
    91 (OPERATIONS IN REDUCED VERTICAL SEPARATION MINIMUM (RVSM) AIRSPACE) 
    were published in April 1997. They are based on the ICAO Manual on 
    RVSM. Technical and operational experts from the FAA, the European 
    Joint Airworthiness Authorities (JAA), the aircraft manufacturers, and 
    pilot associations developed the criteria in a joint FAA/JAA working 
    group. Section 91.706 requires that aircraft and operators meet the 
    requirements of Appendix G and receive authorization from the 
    Administer prior to flying in airspace where RVSM is applied. Appendix 
    G contains requirements in eight sections:
    
    1. Definitions
    2. Aircraft Approval
    3. Operator Authorization
    4. RVSM operations (flight planning into RVSM airspace)
    5. Deviation Authority Approval
    6. Reporting Altitude-keeping Errors
    7. Removal or Amendment of Authority
    8. Airspace Designation
    
        Flight Standards Handbook Bulletin (HBAT) 97-02 entitled ``Approval 
    of Aircraft and Operators for Flight in Airspace Above Flight Level 290 
    Where 1,000 Foot Vertical Separation Minimum Is Applied'', has been 
    distributed through Flight Standards District Offices (FSDOs). This 
    document provides guidance to FAA Flight Standards inspectors on the 
    process and procedures to follow before approving an operator and its 
    aircraft for RVSM operations. It details inspector responsibilities for 
    assessment of airworthiness approval, maintenance program approval, and 
    operations approval requirements in the rule. It discusses timing, 
    process, and maintenance and operations material that the operator 
    should submit for FAA review and evaluation normally at least 60 days 
    before the planned operation in RVSM airspace. Operators under Title 
    14, Code of Federal Regulations (14 CFR) part 91 receive FAA approval 
    in the form of a Letter of Authorization (LOA), and operators under 14 
    CFR parts 121, 125, and 135 receive Operations Specifications (OPS-
    SPEC) approval.
        For operations over the high seas outside the United States, 14 CFR 
    91.703 requires that aircraft of U.S. registry comply with Annex 2 
    (Rules of the Air) to the Convention on International Civil Aviation. 
    Annex 2, amendment 32, effective February 19, 1996, reflects the change 
    from 2,000 feet to 1,000 feet vertical separation for Instrument Flight 
    Rules (IFR) traffic between FL 290 and FL 410, based on appropriate 
    airspace designation, international agreements, and conformance with 
    specified conditions.
    
    General Discussion of the Proposal
    
        The proposal allows operation of civil aircraft of U.S. 
    registration in Pacific oceanic airspace where RVSM is applied. It is 
    based on improvements in altitude-keeping technology. These 
    improvements include:
         Introduction of the air data computer (ADC), which 
    provides an automatic means of correcting the known static source error 
    of aircraft to improve aircraft altitude measurement capability.
         Development of altimeters with enhanced transducers or 
    double aneroid for computing altitude.
        Under this proposal, airspace or routes in the Pacific where RVSM 
    is applied would be considered special qualification airspace. Both the 
    operator and the specific types of aircraft that the operator intends 
    to use in RVSM airspace would have to be approved by the appropriate 
    FAA office before the operator conducts flights in RVSM airspace.
        Implementation of a 1,000-foot vertical separation standard above 
    FL 290 offers substantial operational benefits to operators, including:
         Greater availability of the most fuel-efficient altitudes. 
    In the RVSM environment, aircraft are able to fly closer to their 
    optimum altitude at initial level off and through step climbing to the 
    optimum altitude during the enroute phase.
         Greater availability of the most time and fuel-efficient 
    tracks and routes (and an increased probability of obtaining these 
    tracks and routes). Operators often are not cleared on the track or 
    route that was filed due to demand for the optimum routes and resultant 
    traffic congestion on those routes. RVSM allows ATC to accommodate a 
    greater number of aircraft on a given track or route. More time and 
    fuel-efficient tracks or routes would therefore be available to more 
    aircraft.
         Increased controller flexibility. RVSM gives ATC greater 
    flexibility to manage traffic by increasing the number of flight levels 
    on each track or route.
         Reduction of pilot and controller work load. When 
    controllers are required to re-route aircraft from their filed track 
    and/or altitude they are required to re-coordinate and revise 
    clearances. Pilots are required to re-program aircraft navigation 
    systems (which has been a major cause of navigational errors). RSVM 
    will reduce the number of re-routes required and therefore reduce both 
    pilot and controller workload.
         Enhanced flexibility to allow aircraft to fly across route 
    systems. Operators are often required to remain at lower, less fuel-
    efficient altitudes until the aircraft crosses a route system. RVSM 
    makes more flight levels available at higher, more fuel-efficient 
    altitudes to allow aircraft to cross route systems.
         Enhanced safety in the lateral dimension. Studies indicate 
    that RVSM produces a wider distribution of aircraft among different 
    tracks and altitudes, resulting in less exposure to aircraft at 
    adjacent separation standards. RVSM reduces the number of occasions 
    when two aircraft pass each other separated by a single separation 
    standard (e.g., 60 nm laterally). The benefit to safety is that, should 
    an aircraft enter, as a result of gross navigation error, onto an 
    adjacent track, and another aircraft is on that track, there is an 
    increased probability that the two aircraft would be flying at 
    different flight levels.
        This amendment to Sec. 91.706, Appendix G, Section 8 would add the 
    Pacific oceanic FIRs to the list of FIR's where RVSM can be applied
    
    Regulatory Evaluation Summary
    
        Executive Order 12866 directs federal agencies to promulgate new 
    regulations or modify existing regulations after consideration of the 
    expected benefits to society and the expected costs. Each federal 
    agency shall assess both the costs and the benefits of proposed 
    regulations while recognizing that some costs and benefits are 
    difficult to
    
    [[Page 37023]]
    
    quantify. A proposed rule is promulgated only upon a reasoned 
    determination that the benefits of the proposed rule justify its costs.
        The order also requires federal agencies to assess whether a 
    proposed rule is considered a ``significant regulatory action.'' The 
    Regulatory Flexibility Act of 1980 requires agencies to analyze the 
    economic impact of regulatory changes on small entities. The Office of 
    Management and Budget directs agencies to assess the effect of 
    regulatory changes on international trade. Finally, Public Law 104-4 
    requires federal agencies to assess the impact of any federal mandates 
    on state, local, tribal governments, and the private sector.
        In conducting these analyses, the FAA has determined that this 
    rule: (1) generates benefits that justify its costs and is not ``a 
    significant regulatory action'' as defined in the Executive Order; (2) 
    is significant as defined in Department of Transportation's Regulatory 
    Policies and Procedures; (3) does not have a significant impact on a 
    substantial number of small entities; and (4) does not constitute a 
    barrier to international trade. These analyses, available in the 
    docket, are summarized below.
        This proposal amends FAR 91, Section 91.706, Section 8 (Airspace 
    Designation) by adding the appropriate Pacific Oceanic Flight 
    Information Regions (FIRs) where RVSM would be implemented. The 
    benefits of this proposed rulemaking are (1) an increase in the number 
    of available flight levels, (2) enhance airspace capacity, (3) permit 
    operators to operate more fuel/time efficient tracks and altitudes, and 
    (4) enhance air traffic controller flexibility by increasing the number 
    of available flight levels, while maintaining an equivalent level of 
    safety.
        The FAA estimates that this proposed rule would cost U.S. operators 
    $21.7 million for the ten-year period 2000-2009 or $19.5 million, 
    discounted. Estimated benefits, based on fuel savings for the 
    commercial airplane fleet over the years 2000-2009, would be $120 
    million, or $83.8 million, discounted. Therefore, based on a 
    quantitative and qualitative evaluation of this action, the proposed 
    rule would be cost-beneficial.
    
    Initial Regulatory Flexibility Determination
    
        The Regulatory Flexibility Act of 1980 establishes ``as a principle 
    of regulatory issuance that agencies shall endeavor, consistent with 
    the objective of the rule and of applicable statutes, to fit regulatory 
    and informational requirements to the scale of the business, 
    organizations, and governmental jurisdictions subject to regulation.'' 
    To achieve that principle, the Act requires agencies to solicit and 
    consider flexible regulatory proposals and to explain the rational for 
    their actions. The Act covers a wide-range of small entities, including 
    small businesses, not-for-profit organizations and small governmental 
    jurisdictions.
        Agency must perform a review to determine whether a proposed or 
    final rule will have significant economic impact on a substantial 
    number of small entities. If the determination is that it will, the 
    agency must prepare a regulatory flexibility analysis (RFA) as 
    described in the Act.
        However, if an agency determines that a proposed or final rule is 
    not expected to have a significant economic impact on a substantial 
    number of small entities, section 605(b) of the 1980 act provides that 
    the head of the agency may so certify and an RFA is not required. The 
    certification must include a statement providing the factual basis for 
    this determination, and the reasoning should be clear.
        A review of the Pacific traffic data shows that no small entities 
    operate in Pacific oceanic airspace where this rule applies. The FAA 
    has also examined the impact of this rulemaking on small operators of 
    general aviation aircraft. The FAA database of U.S. registered aircraft 
    operators shows that these airplanes are all operated by commuter or 
    air taxi operators. Commuter or air taxi operators do not operate in 
    Pacific oceanic airspace.
        The FAA has determined that there are reasonable and adequate means 
    to accommodate the transition to RVSM requirements, particularly for 
    general aviation operators (many of whom are small). As of May 1999, 
    50% of the U.S. registered GA aircraft were approved for RVSM 
    operations based on the NAT application of RVSM.
        The FAA conducted the required review of this proposal and 
    determined that it would not have a significant economic impact on a 
    substantial number of small entities. Accordingly, pursuant to the 
    Regulatory Flexibility Act, 5 U.S.C. 605(b), the Federal Aviation 
    Administration certifies that this rule would not have a significant 
    impact on a substantial number of small entities.
    
    International Trade Impact Statement
    
        The provisions of this proposed rule would have little or no impact 
    on trade for U.S. firms doing business in foreign countries and foreign 
    firms doing business in the United States.
    
    Federalism Implications
    
        The regulations proposed herein would not have a substantial direct 
    effect on the State, on the relationship between the national 
    government and the States, or on the distribution of power and 
    responsibilities among the various levels of government. Therefore, in 
    accordance with Executive Order 12612, it is determined that this 
    proposal would not have sufficient federalism implications to warrant 
    the preparation of a Federalism Assessment.
    
    Paperwork Reduction Act of 1995
    
        The reporting and record keeping requirements associated with this 
    rule remain the same as under the current rules and have previously 
    been approved by the Office of Management and Budget under the 
    provisions of the Paperwork Reduction Act of 1980 (Pub. L. 96-511) and 
    have been assigned OMB Control Number 2120-0026. The FAA believers that 
    this rule does not impose any additional record keeping or reporting 
    requirements.
    
    Unfunded Mandates Reform Act of 1995 Assessment
    
        Title II of the Unfunded Mandates Reform Act of 1995 (the Act), 
    enacted as Pub. L. 104-4 on March 22, 1995, requires each Federal 
    agency, to the extent permitted by law, to prepare a written assessment 
    of the effects of any Federal mandate in a proposed or final agency 
    rule that may result in the expenditure by State, local, and tribal 
    governments, in the aggregate, or by the private sector, of $100 
    million or more (adjusted annual for inflation) in any one year. 
    Section 204(a) of the Act, 2 U.S.C. 1534(a), requires the Federal 
    agency to develop an effective process to permit timely input by 
    elected officers (or their designees) of State, local, and tribal 
    governments on a proposed ``significant intergovernmental mandate.'' A 
    ``significant intergovernment mandate'' under the Act is any provision 
    in a Federal agency regulation that would impose an enforceable duty 
    upon state, local, and tribal governments, in the aggregate, of $100 
    million (adjusted annually for inflation) in any one year. Section 203 
    of the Act, 2 U.S.C. 1533, which supplements section 204(a), provides 
    that before establishing any regulatory requirements that might 
    significantly or uniquely affect small governments, the agency shall 
    have developed a plan that, among other things, provides for notice to 
    potentially affected small governments, if any, and for a meaningful 
    and timely opportunity to
    
    [[Page 37024]]
    
    provide input in the development of regulatory proposals.
        This proposed rule does not contain a Federal intergovernmental and 
    private sector mandate that exceeds $100 million a year, therefore, the 
    requirements of Title II of the Unfunded Mandates Reform Act of 1995 do 
    not apply.
    
    International Civil Aviation Organization and Joint Aviation 
    Regulations
    
        In keeping with U.S. obligations under the Convention on 
    International Civil Aviation Organization (ICAO), it is FAA policy to 
    comply with ICAO Standards and Recommended Practices (SARP) to maximum 
    extent practicable. The operator and aircraft approval process was 
    developed jointly by the FAA and the JAA under the auspices of NATSPG. 
    The FAA has determined that this amendment does not present any 
    difference.
    
    Environmental Analysis
    
        FAA Order 1050.1D defines FAA actions that may be categorically 
    excluded from preparation of a National Environmental Policy Act (NEPA) 
    environmental assessment or environmental impact statement. In 
    accordance with FAA Order 1050.1D, appendix 4, paragraph 4(j), 
    regulations, standards, and exemptions (excluding those, which if 
    implemented may cause a significant impact on the human environment) 
    qualify for a categorical exclusion. The FAA proposes that this rule 
    qualifies for a categorical exclusion because no significant impacts to 
    the environment are expected to result from its finalization or 
    implementation.
    
    Energy Impact
    
        The energy impact of this proposed rule has been assessed in 
    accordance with the Energy Policy and Conservation Act (EPCA) and 
    Public Law 94-163, as amended (42 U.S.C. 6362). It has been determined 
    that this proposed rule is not a major regulatory action under the 
    provisions of the EPCA.
    
    List of Subjects in 14 CFR Part 91
    
        Air traffic control, Aircraft, Airmen, Airports, Aviation safety, 
    Reporting and recordkeeping requirements.
    
    The Proposed Amendment
    
        For the reasons discussed in the preamble, the Federal Aviation 
    Administration proposes to amend part 91 of Title 14 of the Code of 
    Federal Regulations (14 CFR part 91) as follows;
    
    PART 91--GENERAL OPERATING AND FLIGHT RULES
    
        1. The authority citation for part 91 continues to read as follows:
    
        Authority: 49 U.S.C. 106(g), 40103, 40113, 40120, 44101, 44111, 
    44701, 44709, 44711, 44712, 44715, 44716, 44717, 44722, 46306, 
    46315, 46316, 46502, 46504, 46506-46507, 47122, 47508, 47528-47531.
    
        2. Part 91, appendix G, is amended by revising Section 8 to read as 
    follows:
    
    Appendix G to Part 91--Operations in Reduced Vertical Separation 
    Minimum (RVSM) Airspace
    
    * * * * *
    
    Section 8. Airspace Designation
    
        (a) RVSM may be applied in the NAT in the following ICAO Flight 
    Information Regions (FIRs): New York Oceanic, Gander Oceanic, 
    Sondrestron FIR, Reykjavik Oceanic, Shanwick Oceanic, and Santa 
    Maria Oceanic.
        (b) RVSM may be applied in the Pacific in the following ICAO 
    Flight Information Regions (FIRs): Anchorage Arctic, Anchorage 
    Continental, Anchorage Oceanic, Auckland Oceanic, Brisbane, 
    Edmonton, Honiara, Los Angeles, Melbourne, Nadi, Naha, Nauru, New 
    Zealand, Oakland, Oakland Oceanic, Port Moresby, Seattle, Tahiti, 
    Tokyo, and Vancouver.
        (c) RVSM may be effective in the Minimum Navigation Performance 
    Specification (MNPS) airspace within the NAT. The MNPS airspace 
    within the NAT is defined by the volume of airspace FL 285 and FL 
    420 extending between latitude 27 degrees north and the North Pole, 
    bounded in the east by the eastern boundaries of control areas Santa 
    Maria Oceanic, Shanwick Oceanic, and Reykjavik Oceanic and in the 
    west by the western boundaries of control areas Reykjavik Oceanic, 
    Gander Oceanic, and New York Oceanic, excluding the areas west of 60 
    degrees west and south of 38 degrees 30 minutes north.
    
        Issued in Washington, DC, on June 30, 1999.
    L. Nicholas Lacey,
    Director, Flight Standards Service.
    [FR Doc. 99-17360 Filed 7-7-99; 8:45 am]
    BILLING CODE 4910-13-M
    
    
    

Document Information

Published:
07/08/1999
Department:
Federal Aviation Administration
Entry Type:
Proposed Rule
Action:
Notice of proposed rulemaking (NPRM).
Document Number:
99-17360
Dates:
Comments must be submitted on or before September 7, 1999.
Pages:
37018-37024 (7 pages)
Docket Numbers:
Docket No. FAA-1999-5925, Notice No. 99-10
RINs:
2120-AG82: Reduced Vertical Separation Minimum
RIN Links:
https://www.federalregister.gov/regulations/2120-AG82/reduced-vertical-separation-minimum
PDF File:
99-17360.pdf
CFR: (1)
14 CFR 91