97-4715. Airworthiness Directives; Airbus Model A320 Series Airplanes  

  • [Federal Register Volume 62, Number 39 (Thursday, February 27, 1997)]
    [Rules and Regulations]
    [Pages 8872-8873]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-4715]
    
    
    
    [[Page 8872]]
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 96-NM-11-AD; Amendment 39-9948; AD 97-05-04]
    RIN 2120-AA64
    
    
    Airworthiness Directives; Airbus Model A320 Series Airplanes
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule.
    
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    SUMMARY: This amendment supersedes an existing airworthiness directive 
    (AD), applicable to certain Airbus Model A320-111, -211, and -231 
    series airplanes, that currently requires replacing the existing 
    standby generator control unit (GCU) with a new improved standby GCU. 
    That action was prompted by reports of improper functioning of the 
    standby GCU. This amendment requires replacement of the GCU on addition 
    affected airplanes. For some airplanes, it also will require that a 
    wiring modification be accomplished prior to replacement of the GCU. 
    The actions specified by this AD are intended to prevent such improper 
    functioning of the GCU, which could result in the loss of the standby 
    emergency generation system.
    
    DATES: Effective April 3, 1997.
        The incorporation by reference of certain publications, as listed 
    in the regulations, is approved by the Director of the Federal Register 
    as of April 3, 1997.
    
    ADDRESSES: The service information referenced in this AD may be 
    obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
    Blagnac Cedex, France. This information may be examined at the Federal 
    Aviation Administration (FAA), Transport Airplane Directorate, Rules 
    Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of 
    the Federal Register, 800 North Capitol Street, NW., suite 700, 
    Washington, DC.
    
    FOR FURTHER INFORMATION CONTACT: Tim Backman, Aerospace Engineer, 
    Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
    1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
    227-2797; fax (206) 227-1149.
    
    SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
    Aviation Regulations (14 CFR part 39) by superseding AD 91-01-01, 
    amendment 39-6845 (55 FR 51895, December 18, 1990), which is applicable 
    to certain Airbus Model A320-111, -211, and -231 series airplanes, was 
    published in the Federal Register on October 23, 1996 (61 FR 54963). 
    The action proposed to supersede AD 91-01-01 to continue to require 
    replacement of the existing standby GCU with an improved standby GCU. 
    The action also proposed to require the identical replacement to be 
    accomplished on additional airplanes. In addition, for some airplanes, 
    the action proposed that a wiring modification be accomplished prior to 
    replacement of the GCU.
        Interested persons have been afforded an opportunity to participate 
    in the making of this amendment. Due consideration has been given to 
    the two comments received.
    
    Support for the Proposal
    
        Both commenters support the proposed AD.
    
    Conclusion
    
        After careful review of the available data, including the comments 
    noted above, the FAA has determined that air safety and the public 
    interest require the adoption of the rule as proposed.
    
    Cost Impact
    
        There are approximately 106 Airbus Model A320 series airplanes of 
    U.S. registry that will be affected by this AD. Of this number, 18 were 
    previously subject to the requirements of AD 91-01-01, and the 
    remaining 88 are the airplanes that have been added to the AD 
    applicability by this action.
        The replacement of the GCU that is required by this AD takes 
    approximately 1.5 work hours per airplane to accomplish, at an average 
    labor rate of $60 per work hour. Required parts will cost approximately 
    $450 per airplane. Based on these figures, the cost impact of this 
    required action on U.S. operators is estimated to be $57,240 for the 
    entire affected fleet (or $540 per airplane). However, based on the 
    effective date and the compliance time established by AD 91-01-01, the 
    FAA assumes that the 18 airplanes that were previously subject to that 
    AD already have completed the required replacement of the GCU. 
    Therefore, the future cost impact of the replacement action is only 
    $47,520 (for the 88 airplanes that have been added to the applicability 
    of the AD).
        For airplanes on which the modification of the wiring assembly is 
    required, it will take approximately 8.5 work hours to accomplish, at 
    an average labor rate of $60 per work hour. Based on these figures, the 
    cost impact of this action on U.S. operators of those airplanes is 
    estimated to be $510 per airplane.
        The cost impact figures discussed above are based on assumptions 
    that no operator has yet accomplished any of the new requirements of 
    this AD action, and that no operator would accomplish those actions in 
    the future if this AD were not adopted.
    
    Regulatory Impact
    
        The regulations adopted herein will not have substantial direct 
    effects on the States, 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 final 
    rule does not have sufficient federalism implications to warrant the 
    preparation of a Federalism Assessment.
        For the reasons discussed above, I certify that this action (1) is 
    not a ``significant regulatory action'' under Executive Order 12866; 
    (2) is not a ``significant rule'' under DOT Regulatory Policies and 
    Procedures (44 FR 11034, February 26, 1979); and (3) will not have a 
    significant economic impact, positive or negative, on a substantial 
    number of small entities under the criteria of the Regulatory 
    Flexibility Act. A final evaluation has been prepared for this action 
    and it is contained in the Rules Docket. A copy of it may be obtained 
    from the Rules Docket at the location provided under the caption 
    ADDRESSES.
    
    List of Subjects in 14 CFR Part 39
    
        Air transportation, Aircraft, Aviation safety, Incorporation by 
    reference, Safety.
    
    Adoption of the Amendment
    
        Accordingly, pursuant to the authority delegated to me by the 
    Administrator, the Federal Aviation Administration amends part 39 of 
    the Federal Aviation Regulations (14 CFR part 39) as follows:
    
    PART 39--AIRWORTHINESS DIRECTIVES
    
        1. The authority citation for part 39 continues to read as follows:
    
        Authority: 49 U.S.C. 106(g), 40113, 44701.
    
    
    Sec. 39.13  [Amended]
    
        2. Section 39.13 is amended by removing amendment 39-6845 (55 FR 
    51895, December 18, 1990), and by adding a new airworthiness directive
    
    [[Page 8873]]
    
    (AD), amendment 39-9948, to read as follows:
    
    97-05-04 Airbus Industrie: Amendment 39-9948. Docket 96-NM-11-AD. 
    Supersedes AD 91-01-01, Amendment 39-6845.
    
        Applicability: Model A320 series airplanes; on which a generator 
    control unit (GCU) having part number (P/N) 520915 has not been 
    installed, or on which Airbus Modification 21052 (reference Airbus 
    Service Bulletin A320-24-1022) and Airbus Modification 21736 
    (reference Airbus Service Bulletin A320-24-1035) have not been 
    accomplished; certificated in any category.
    
        Note 1: This AD applies to each airplane identified in the 
    preceding applicability provision, regardless of whether it has been 
    modified, altered, or repaired in the area subject to the 
    requirements of this AD. For airplanes that have been modified, 
    altered, or repaired so that the performance of the requirements of 
    this AD is affected, the owner/operator must request approval for an 
    alternative method of compliance in accordance with paragraph (c) of 
    this AD. The request should include an assessment of the effect of 
    the modification, alteration, or repair on the unsafe condition 
    addressed by this AD; and, if the unsafe condition has not been 
    eliminated, the request should include specific proposed actions to 
    address it.
    
        Compliance: Required as indicated, unless accomplished 
    previously.
        To prevent loss of the standby emergency generation system, 
    which provides necessary back-up capability when both main 
    generators fail, accomplish the following:
    
        Note 2: Airbus Service Bulletin A320-24-1035 and Airbus Service 
    Bulletin A320-24-1022 refer to Vickers Service Bulletin No. 520754-
    24-01 as an additional source of specific procedural information.
    
        (a) For Model A320-111, -211, and -231 series airplanes; having 
    serial numbers 003 through 058, inclusive, 060 through 067, 
    inclusive, 069 through 072, inclusive, 074 through 083, inclusive, 
    and 085: Within 150 days after January 28, 1991 (the effective date 
    of AD 91-01-01, amendment 39-6845), remove one generator control 
    unit (GCU) identified as 1XE part number (P/N) 520754, and install a 
    modified GCU identified as 1XE, P/N 520915, in accordance with 
    Airbus Service Bulletin A320-24-1035, Revision 1, dated February 27, 
    1990, or Revision 2, dated June 24, 1994. Following installation, 
    perform an operational test of the emergency generation system, 
    emergency GCU from the centralized fault display system, and the 
    static inverter, in accordance with the service bulletin.
        (b) For airplanes not subject to paragraph (a) of this AD: 
    Within 150 days after the effective date of this AD, accomplish 
    either paragraph (b)(1) or (b)(2) of this AD, as applicable.
    
        Note 3: Replacement of the GCU accomplished prior to the 
    effective date of this AD in accordance with Airbus Service Bulletin 
    A320-24-1035, Revision 1, dated February 27, 1990, is considered 
    acceptable for compliance with the actions specified in this 
    paragraph.
    
        (1) For airplanes equipped with GCU 1XE having P/N 520754: 
    Replace the GCU 1XE, having P/N 520754, in zone 125 of the avionics 
    compartment, with a modified GCU 1XE, having P/N 520915, in 
    accordance with Airbus Service Bulletin A320-24-1035, Revision 2, 
    dated June 24, 1994. Prior to further flight following 
    accomplishment of the replacement, perform an operational test of 
    the affected components in accordance with that service bulletin.
        (2) For airplanes equipped with GCU 1XE having P/N 520738: 
    Accomplish the requirements of paragraphs (b)(2)(i) and (b)(2)(ii) 
    of this AD:
        (i) Modify the wiring in relay box 103VU, the wiring in power 
    center AC/DC emergency 106VU, and the wiring between 103VU and 
    106VU, in accordance with Airbus Service Bulletin A320-24-1022, 
    Revision 1, dated February 27, 1990.
    
        Note 4: Modification accomplished prior to the effective date of 
    this AD in accordance with Airbus Service Bulletin A320-24-1022, 
    dated June 16, 1989, is considered acceptable for compliance with 
    this paragraph.
    
        (ii) After modifying the wiring, replace the GCU 1XE, having P/N 
    520738, located in the nose gear well in zone 125, with a modified 
    GCU 1XE, having P/N 520915, in accordance with Airbus Service 
    Bulletin A320-24-1035, Revision 2, dated June 24, 1994. Prior to 
    further flight following accomplishment of the replacement, perform 
    an operational test of the affected components in accordance with 
    that service bulletin.
        (c) An alternative method of compliance or adjustment of the 
    compliance time that provides an acceptable level of safety may be 
    used if approved by the Manager, Manager, Standardization Branch, 
    ANM-113, FAA, Transport Airplane Directorate. Operators shall submit 
    their requests through an appropriate FAA Principal Maintenance 
    Inspector, who may add comments and then send it to the Manager, 
    Standardization Branch, ANM-113.
    
        Note 5: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the Standardization Branch, ANM-113.
    
        (d) Special flight permits may be issued in accordance with 
    sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
    CFR 21.197 and 21.199) to operate the airplane to a location where 
    the requirements of this AD can be accomplished.
        (e) The actions shall be done in accordance with the following 
    Airbus Service Bulletins, which contain the specified lists 
    effective pages:
    
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      Service bulletin number and date                       Page No.                       Revision level shown on page           Date shown on page       
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    A320-24-1035, Revision 1, February   1, 2...........................................  1...............................  February 27, 1990.              
     27, 1990.                           3, 4...........................................  Original........................  October 20, 1989.               
    A320-24-1035, Revision 2, June 24,   1-4............................................  2...............................  June 24, 1994.                  
     1994.                                                                                                                                                  
    A320-24-1022, Revision 1, February   1, 5, 6, 13, 14, 19-21.........................  1...............................  February 27, 1990.              
     27, 1990.                           2-4, 7-12, 15-18, 22...........................  Original........................  June 16, 1989.                  
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        The incorporation by reference of the service documents listed 
    above is approved by the Director of the Federal Register in accordance 
    with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from 
    Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, 
    France. Copies may be inspected at the FAA, Transport Airplane 
    Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the 
    Office of the Federal Register, 800 North Capitol Street, NW., suite 
    700, Washington, DC.
        (f) This amendment becomes effective on April 3, 1997.
    
        Issued in Renton, Washington, on February 20, 1997.
    James V. Devany,
    Acting Manager, Transport Airplane Directorate, Aircraft Certification 
    Service.
    [FR Doc. 97-4715 Filed 2-26-97; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
4/3/1997
Published:
02/27/1997
Department:
Federal Aviation Administration
Entry Type:
Rule
Action:
Final rule.
Document Number:
97-4715
Dates:
Effective April 3, 1997.
Pages:
8872-8873 (2 pages)
Docket Numbers:
Docket No. 96-NM-11-AD, Amendment 39-9948, AD 97-05-04
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
97-4715.pdf
CFR: (1)
14 CFR 39.13