98-28966. Airworthiness Directives; Slingsby Aviation Limited Models Dart T.51, Dart T.51/17, and Dart T.51/17R Sailplanes  

  • [Federal Register Volume 63, Number 211 (Monday, November 2, 1998)]
    [Rules and Regulations]
    [Pages 58624-58625]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 98-28966]
    
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 98-CE-67-AD; Amendment 39-10863; AD 98-22-15]
    RIN 2120-AA64
    
    
    Airworthiness Directives; Slingsby Aviation Limited Models Dart 
    T.51, Dart T.51/17, and Dart T.51/17R Sailplanes
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule.
    
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    SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
    applies to all Slingsby Aviation Limited (Slingsby) Models Dart T.51, 
    Dart T.51/17, and Dart T.51/17R sailplanes that are equipped with 
    aluminum alloy spar booms. This AD requires repetitively inspecting the 
    aluminum alloy spar booms and the wing attach fittings for delamination 
    or corrosion damage, and repairing any delamination or corrosion damage 
    found. This AD is the result of mandatory continuing airworthiness 
    information (MCAI) issued by the airworthiness authority for the United 
    Kingdom. The actions specified by this AD are intended to prevent 
    failure of the spar assembly and adjoining structure caused by 
    delamination or corrosion damage to the aluminum alloy spar booms or 
    the wing attach fittings, which could result in reduced controllability 
    or loss of control of the sailplane.
    
    DATES: Effective December 14, 1998.
        The incorporation by reference of certain publications listed in 
    the regulations is approved by the Director of the Federal Register as 
    of December 14, 1998.
    
    ADDRESSES: Service information that applies to this AD may be obtained 
    from Slingsby Aviation Ltd., Kirbymoorside, York Y06 6EZ England; 
    telephone: +44(0)1751 432474; facsimile: +44(0)1751 431173. This 
    information may also be examined at the Federal Aviation Administration 
    (FAA), Central Region, Office of the Regional Counsel, Attention: Rules 
    Docket No. 98-CE-67-AD, Room 1558, 601 E. 12th Street, Kansas City, 
    Missouri 64106; or at the Office of the Federal Register, 800 North 
    Capitol Street, NW, suite 700, Washington, DC.
    
    FOR FURTHER INFORMATION CONTACT: Mr. Mike Kiesov, Aerospace Engineer, 
    FAA, Small Airplane Directorate, 1201 Walnut, suite 900, Kansas City, 
    Missouri 64106; telephone: (816) 426-6934; facsimile: (816) 426-2169.
    
    SUPPLEMENTARY INFORMATION:
    
    Events Leading to the Issuance of This AD
    
        A proposal to amend part 39 of the Federal Aviation Regulations (14 
    CFR part 39) to include an AD that would apply to all Slingsby Models 
    Dart T.51, Dart T.51/17, and Dart T.51/17R sailplanes that are equipped 
    with aluminum alloy spar booms was published in the Federal Register as 
    a notice of proposed rulemaking (NPRM) on July 15, 1998 (63 FR 38126). 
    The NPRM proposed to require repetitively inspecting the aluminum alloy 
    spar booms and the wing attach fittings for delamination or corrosion 
    damage, and repairing any delamination or corrosion damage found. 
    Accomplishment of the proposed action as specified in the NPRM would be 
    in accordance with Slingsby Technical Instruction (TI) No. 109/T51, 
    Issue No. 2, dated October 7, 1997.
        The NPRM was the result of mandatory continuing airworthiness 
    information (MCAI) issued by the airworthiness authority for the United 
    Kingdom.
        Interested persons have been afforded an opportunity to participate 
    in the making of this amendment. No comments were received on the 
    proposed rule or the FAA's determination of the cost to the public.
    
    The FAA's Determination
    
        After careful review of all available information related to the 
    subject presented above, the FAA has determined that air safety and the 
    public interest require the adoption of the rule as proposed except for 
    minor editorial corrections. The FAA has determined that these minor 
    corrections will not change the meaning of the AD and will not add any 
    additional burden upon the public than was already proposed.
    
    Compliance Time of This AD
    
        The unsafe condition specified by this AD is caused by corrosion. 
    Corrosion can occur regardless of whether the aircraft is in operation 
    or is in storage. Therefore, to assure that the unsafe condition 
    specified in this AD does not go undetected for a long period of time, 
    the compliance is presented in calendar time instead of hours time-in-
    service (TIS).
    
    Differences Between the British AD, the Technical Instruction, and 
    This AD
    
        Both Slingsby TI No. 109/T51, Issue No. 2, dated October 7, 1997, 
    and British AD 005-09-97, dated October 3, 1997, specify the initial 
    inspection prior to further flight.
        The FAA does not have justification through its regulatory process 
    to require the initial inspection prior to further flight. To assure 
    that no affected sailplanes are inadvertently grounded, the FAA is 
    utilizing a compliance time of 6 calendar months for the initial 
    inspection.
    
    Cost Impact
    
        The FAA estimates that 3 sailplanes in the U.S. registry will be 
    affected by this AD, that it will take approximately 40 workhours per 
    sailplane to accomplish the initial inspection, and that the average 
    labor rate is approximately $60 an hour. Based on these figures, the 
    total cost impact of the initial inspection specified in this AD on 
    U.S. operators is estimated to be $7,200, or $2,400 per sailplane.
        These figures only take into account the costs of the initial 
    inspection and do not take into account the costs of repetitive 
    inspections and the costs associated with any repair that will be 
    necessary if corrosion or delamination damage is found. The FAA has no 
    way of determining the number of repetitive inspections an owner/
    operator will incur over the life of the sailplane, or the number of 
    sailplanes that will need repairs.
    
    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 copy of the final
    
    [[Page 58625]]
    
    evaluation prepared for this action is contained 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, 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 adding a new airworthiness directive 
    (AD) to read as follows:
    
    98-22-15  Slingsby Aviation Limited (Type Certificate No. G5EU 
    formerly held by Slingsby Sailplanes Ltd.): Amendment 39-10863; 
    Docket No. 98-CE-67-AD.
    
        Applicability: Models Dart T.51, Dart T.51/17, and Dart T.51/17R 
    sailplanes, all serial numbers, certificated in any category, that 
    are equipped with aluminum alloy spar booms.
    
        Note 1: This AD applies to each sailplane 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 sailplanes 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 failure of the spar assembly and adjoining structure 
    caused by delamination or corrosion damage to the aluminum alloy 
    spar booms or the wing attach fittings, which could result in 
    reduced controllability or loss of control of the sailplane, 
    accomplish the following:
        (a) Within the next 6 calendar months after the effective date 
    of this AD and thereafter at intervals not to exceed 5 years, 
    inspect the aluminum alloy spar booms and the wing attach fittings 
    for delamination or corrosion damage. Accomplish this inspection in 
    accordance with Slingsby Technical Instruction (TI) No. 109/T51, 
    Issue No. 2, dated October 7, 1997.
    
        Note 2: Slingsby TI No. 109/T51, Issue No. 2, dated October 7, 
    1997, includes guidance to determine whether an affected sailplane 
    is equipped with aluminum alloy spar booms.
    
        (b) If any corrosion or delamination damage is found during any 
    inspection required by paragraph (a) of this AD, prior to further 
    flight, accomplish the following:
        (1) Obtain a repair scheme from the manufacturer through the 
    FAA, Small Airplane Directorate, at the address specified in 
    paragraph (d) of this AD; and
        (2) Incorporate this scheme and continue to repetitively inspect 
    as required by paragraph (a) of this AD, unless specified 
    differently in the instructions to the repair scheme.
        (c) 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 sailplane to a location where 
    the requirements of this AD can be accomplished.
        (d) An alternative method of compliance or adjustment of the 
    initial or repetitive compliance times that provides an equivalent 
    level of safety may be approved by the Manager, Small Airplane 
    Directorate, FAA, 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 3: 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 Slingsby TI 
    No. 109/T51, Issue No. 2, dated October 7, 1997, should be directed 
    to Slingsby Aviation Ltd., Kirbymoorside, York Y06 6EZ England; 
    telephone: +44(0)1751 432474; facsimile: +44(0)1751 431173. 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.
        (f) The inspection required by this AD shall be done in 
    accordance with Slingsby Technical Instruction No. 109/T51, Issue 
    No. 2, dated October 7, 1997. This incorporation by reference was 
    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 
    Slingsby Aviation Ltd., Kirbymoorside, York Y06 6EZ England. Copies 
    may be inspected at the FAA, Central Region, Office of the Regional 
    Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at 
    the Office of the Federal Register, 800 North Capitol Street, NW, 
    suite 700, Washington, DC.
    
        Note 4: The subject of this AD is addressed in British AD 005-
    09-97, dated October 3, 1997.
    
        (g) This amendment becomes effective on December 14, 1998.
    
        Issued in Kansas City, Missouri, on October 22, 1998.
    Michael Gallagher,
    Manager, Small Airplane Directorate, Aircraft Certification Service.
    [FR Doc. 98-28966 Filed 10-30-98; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
12/14/1998
Published:
11/02/1998
Department:
Federal Aviation Administration
Entry Type:
Rule
Action:
Final rule.
Document Number:
98-28966
Dates:
Effective December 14, 1998.
Pages:
58624-58625 (2 pages)
Docket Numbers:
Docket No. 98-CE-67-AD, Amendment 39-10863, AD 98-22-15
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
98-28966.pdf
CFR: (1)
14 CFR 39.13