99-21017. Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and PC-12/45 Airplanes  

  • [Federal Register Volume 64, Number 156 (Friday, August 13, 1999)]
    [Proposed Rules]
    [Pages 44137-44139]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 99-21017]
    
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 99-CE-54-AD]
    RIN 2120-AA64
    
    
    Airworthiness Directives; Pilatus Aircraft Ltd. Models PC-12 and 
    PC-12/45 Airplanes
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Notice of proposed rulemaking (NPRM).
    
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    SUMMARY: This document proposes to adopt a new airworthiness directive
    
    [[Page 44138]]
    
    (AD) that would apply to certain Pilatus Aircraft Ltd. (Pilatus) Models 
    PC-12 and PC-12/45 airplanes. The proposed AD would require modifying 
    the flap inboard attachment fittings through the installation of a 
    reinforcement angle bracket on the inside of the center web of both 
    flap inner attachment fittings. The proposed AD is the result of 
    mandatory continuing airworthiness information (MCAI) issued by the 
    airworthiness authority for Switzerland. The actions specified by the 
    proposed AD are intended to prevent the potential of the inboard flap 
    attachment fittings buckling while operating at full flaps with full 
    power into a head-on wind gust, which could result in loss of control 
    of the airplane.
    
    DATES: Comments must be received on or before September 13, 1999.
    
    ADDRESSES: Submit comments in triplicate to the Federal Aviation 
    Administration (FAA), Central Region, Office of the Regional Counsel, 
    Attention: Rules Docket No. 99-CE-54-AD, Room 1558, 601 E. 12th Street, 
    Kansas City, Missouri 64106. Comments may be inspected at this location 
    between 8 a.m. and 4 p.m., Monday through Friday, holidays excepted.
        Service information that applies to the proposed AD may be obtained 
    from Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, 
    Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 610 33 51. 
    This information also may be examined at the Rules Docket at the 
    address above.
    
    FOR FURTHER INFORMATION CONTACT: Mr. Roman T. Gabrys, Aerospace 
    Engineer, FAA, Small Airplane Directorate, 1201 Walnut, suite 900, 
    Kansas City, Missouri 64106; telephone: (816) 426-6932; facsimile: 
    (816) 426-2169.
    
    SUPPLEMENTARY INFORMATION:
    
    Comments Invited
    
        Interested persons are invited to participate in the making of the 
    proposed rule by submitting such written data, views, or arguments as 
    they may desire. Communications should identify the Rules Docket number 
    and be submitted in triplicate to the address specified above. All 
    communications received on or before the closing date for comments, 
    specified above, will be considered before taking action on the 
    proposed rule. The proposals contained in this notice may be changed in 
    light of the comments received.
        Comments are specifically invited on the overall regulatory, 
    economic, environmental, and energy aspects of the proposed rule. All 
    comments submitted will be available, both before and after the closing 
    date for comments, in the Rules Docket for examination by interested 
    persons. A report that summarizes each FAA-public contact concerned 
    with the substance of this proposal will be filed in the Rules Docket.
        Commenters wishing the FAA to acknowledge receipt of their comments 
    submitted in response to this notice must submit a self-addressed, 
    stamped postcard on which the following statement is made: ``Comments 
    to Docket No. 99-CE-54-AD.'' The postcard will be date stamped and 
    returned to the commenter.
    
    Availability of NPRMs
    
        Any person may obtain a copy of this NPRM by submitting a request 
    to the FAA, Central Region, Office of the Regional Counsel, Attention: 
    Rules Docket No. 99-CE-54-AD, Room 1558, 601 E. 12th Street, Kansas 
    City, Missouri 64106.
    
    Discussion
    
        The Federal Office for Civil Aviation (FOCA), which is the 
    airworthiness authority for Switzerland, recently notified the FAA that 
    an unsafe condition may exist on certain Pilatus Models PC-12 and PC-
    12/45 airplanes. The FOCA of Switzerland reports that static testing 
    shows that insufficient safety margins could occur in certain 
    situations. Operating the airplane at full flaps (at the maximum 
    allowable aircraft speed) with full power into a head-on wind gust 
    could result in the inboard flap attachment fittings buckling.
        This condition, if not corrected, could result in loss of control 
    of the airplane.
    
    Relevant Service Information
    
        Pilatus has issued Service Bulletin No. 57-004, dated June 11, 
    1999, which specifies procedures for modifying the flap inboard 
    attachment fittings through the installation of a reinforcement angle 
    bracket on the inside of the center web of both flap inner attachment 
    fittings.
        The FOCA of Switzerland classified this service bulletin as 
    mandatory and issued Swiss AD HB 99-353, dated July 12, 1999, in order 
    to assure the continued airworthiness of these airplanes in 
    Switzerland.
    
    The FAA's Determination
    
        This airplane model is manufactured in Switzerland and is type 
    certificated for operation in the United States under the provisions of 
    Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the 
    applicable bilateral airworthiness agreement. Pursuant to this 
    bilateral airworthiness agreement, the FOCA of Switzerland has kept the 
    FAA informed of the situation described above.
        The FAA has examined the findings of the FOCA of Switzerland; 
    reviewed all available information, including the service information 
    referenced above; and determined that AD action is necessary for 
    products of this type design that are certificated for operation in the 
    United States.
    
    Explanation of the Provisions of the Proposed AD
    
        Since an unsafe condition has been identified that is likely to 
    exist or develop in other Pilatus PC-12 and PC-12/45 airplanes of the 
    same type design registered in the United States, the FAA is proposing 
    AD action. The proposed AD would require modifying the flap inboard 
    attachment fittings through the installation of a reinforcement angle 
    bracket on the inside of the center web of both flap inner attachment 
    fittings. Accomplishment of the proposed action would be required in 
    accordance with Pilatus Service Bulletin No. 57-004, dated June 11, 
    1999.
    
    Cost Impact
    
        The FAA estimates that 77 airplanes in the U.S. registry would be 
    affected by the proposed AD, that it would take approximately 5 
    workhours per airplane to accomplish the proposed action, and that the 
    average labor rate is approximately $60 an hour. Parts will be provided 
    by the manufacturer at no cost to the owners/operators of the affected 
    airplanes. Based on these figures, the total cost impact of the 
    proposed AD on U.S. operators is estimated to be $23,100, or $300 per 
    airplane.
    
    Regulatory Impact
    
        The regulations proposed herein would 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 
    proposal would 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) if promulgated, 
    will not have a significant economic impact, positive or negative, on a 
    substantial number of small entities under the criteria of the 
    Regulatory
    
    [[Page 44139]]
    
    Flexibility Act. A copy of the draft regulatory evaluation prepared for 
    this action has been placed in the Rules Docket. A copy of it may be 
    obtained by contacting the Rules Docket at the location provided under 
    the caption ADDRESSES.
    
    List of Subjects in 14 CFR Part 39
    
        Air transportation, Aircraft, Aviation safety, Safety.
    
    The Proposed Amendment
    
        Accordingly, pursuant to the authority delegated to me by the 
    Administrator, the Federal Aviation Administration proposes to amend 
    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 adding a new airworthiness directive 
    (AD) to read as follows:
    
    Pilatus Aircraft Ltd.: Docket No. 99-CE-54-AD.
    
        Applicability: Models PC-12 and PC-12/45 airplanes, manufacturer 
    serial number (MSN) 101 through MSN 300, 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 (d) 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 in the body of this AD, unless 
    already accomplished.
        To prevent the potential for the inboard flap attachment 
    fittings buckling while operating at full flaps with full power into 
    a head-on wind gust, which could result in loss of control of the 
    airplane, accomplish the following:
        (a) Within the next 100 hours time-in-service (TIS) after the 
    effective date of this AD, modify the flap inboard attachment 
    fittings by installing a reinforcement angle bracket on the inside 
    of the center web of both flap inner attachment fittings 
    (Modification Kit Number 500.50.12.199). Accomplish this 
    modification in accordance with the Accomplishment Instructions 
    section of Pilatus Service Bulletin No. 57-004, dated June 11, 1999.
        (b) As of the effective date of this AD, no person may install 
    on any of the affected airplanes, flap inboard attachment fittings 
    that do not have Modification Kit Number 500.50.12.199 incorporated.
        (c) Special flight permits may be issued in accordance with 
    Secs. 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.
        (d) An alternative method of compliance or adjustment of the 
    compliance times that provides an equivalent level of safety may be 
    approved by the Manager, Small Airplane Directorate, 1201 Walnut, 
    suite 900, Kansas City, Missouri 64106. The request shall be 
    forwarded through an appropriate FAA Maintenance Inspector, who may 
    add comments and then send it to the Manager, Small Airplane 
    Directorate.
    
        Note 2: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the Small Airplane Directorate.
    
        (e) Questions or technical information related to Pilatus 
    Service Bulletin No: 57-004, dated June 11, 1999, should be directed 
    to Pilatus Aircraft Ltd., Customer Liaison Manager, CH-6371 Stans, 
    Switzerland; telephone: +41 41 619 63 19; facsimile: +41 41 610 33 
    51. This service information may be examined at the FAA, Central 
    Region, Office of the Regional Counsel, Room 1558, 601 E. 12th 
    Street, Kansas City, Missouri 64106.
    
        Note 3: The subject of this AD is addressed in Swiss AD HB 99-
    353, dated July 12, 1999.
    
        Issued in Kansas City, Missouri, on August 6, 1999.
    Michael Gallagher,
    Manager, Small Airplane Directorate, Aircraft Certification Service.
    [FR Doc. 99-21017 Filed 8-12-99; 8:45 am]
    BILLING CODE 4910-13-P
    
    
    

Document Information

Published:
08/13/1999
Department:
Federal Aviation Administration
Entry Type:
Proposed Rule
Action:
Notice of proposed rulemaking (NPRM).
Document Number:
99-21017
Dates:
Comments must be received on or before September 13, 1999.
Pages:
44137-44139 (3 pages)
Docket Numbers:
Docket No. 99-CE-54-AD
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
99-21017.pdf
CFR: (2)
14 CFR 21.29
14 CFR 39.13