94-9730. Airworthiness Directives; de Havilland, Inc., Model DHC-7 Series Airplanes  

  • [Federal Register Volume 59, Number 86 (Thursday, May 5, 1994)]
    [Unknown Section]
    [Page 0]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 94-9730]
    
    
    [[Page Unknown]]
    
    [Federal Register: May 5, 1994]
    
    
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    DEPARTMENT OF TRANSPORTATION
    14 CFR Part 39
    
    [Docket No. 92-NM-157-AD; Amendment 39-8893; AD 94-09-05]
    
     
    
    Airworthiness Directives; de Havilland, Inc., Model DHC-7 Series 
    Airplanes
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule.
    
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    SUMMARY: This amendment adopts a new airworthiness directive (AD), 
    applicable to certain de Havilland Model DHC-7 series airplanes, that 
    requires a one-time inspection to assess the adequacy of the clearance 
    between various adapter plates and seal retaining angles on the 
    fuselage side access panel, and modification of both the forward and 
    rear seal retention angles. This amendment is prompted by reports of 
    incidents involving corrosion and fatigue cracking in commuter-class 
    airplanes that are approaching or have exceeded their economic design 
    goal. The actions specified by this AD are intended to prevent 
    degradation of the structural capabilities of the affected airplanes.
    
    DATES: Effective June 6, 1994.
        The incorporation by reference of certain publications listed in 
    the regulations is approved by the Director of the Federal Register as 
    of June 6, 1994.
    
    ADDRESSES: The service information referenced in this AD may be 
    obtained from de Havilland, Inc., Garratt Boulevard, Downsview, Ontario 
    M3K 1Y5, Canada. 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 FAA, 
    Engine and Propeller Directorate, New York Aircraft Certification 
    Office, 181 South Franklin Avenue, room 202, Valley Stream, New York; 
    or at the Office of the Federal Register, 800 North Capitol Street, 
    NW., suite 700, Washington, DC.
    
    FOR FURTHER INFORMATION CONTACT: Sol Maroof, Aerospace Engineer, 
    Airframe Branch, ANE-172, FAA, New York Aircraft Certification Office, 
    181 South Franklin Avenue, room 202, Valley Stream, New York 11581; 
    telephone (516) 791-6220; fax (516) 791-9024.
    
    SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
    Aviation Regulations to include an airworthiness directive (AD) that is 
    applicable to certain de Havilland Model DHC-7 series airplanes was 
    published as a supplemental notice of proposed rulemaking (NPRM) in the 
    Federal Register on January 4, 1994 (59 FR 266). That action proposed 
    to require a one-time inspection to assess the adequacy of the 
    clearance between various adapter plates and seal retaining angles on 
    the fuselage side access panel, and modification of both the forward 
    and rear seal retention angles.
        Interested persons have been afforded an opportunity to participate 
    in the making of this amendment. Due consideration has been given to 
    the single comment received.
        The commenter supports the proposed rule.
        After careful review of the available data, including the comment 
    noted above, the FAA has determined that air safety and the public 
    interest require the adoption of the rule as proposed.
        The FAA estimates that 44 airplanes of U.S. registry will be 
    affected by this AD, that it will take approximately 8 work hours per 
    airplane to accomplish the modifications and inspections, and that the 
    average labor rate is $55 per work hour. Required parts will be nominal 
    in cost. Based on these figures, the total cost impact of the AD on 
    U.S. operators is estimated to be $19,360, or $440 per airplane.
        The total cost impact figure discussed above is based on 
    assumptions that no operator has yet accomplished any of the 
    requirements of this AD action, and that no operator would accomplish 
    those actions in the future if this AD were not adopted.
        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 14 CFR part 
    39 of the Federal Aviation Regulations as follows:
    
    PART 39--AIRWORTHINESS DIRECTIVES
    
        1. The authority citation for part 39 continues to read as follows:
    
        Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
    106(g); and 14 CFR 11.89.
    
    
    39.13  [Amended]
    
        2. Section 39.13 is amended by adding the following new 
    airworthiness directive:
    
    94-09-05 De Havilland, Inc.: Amendment 39-8893. Docket 92-NM-157-AD.
    
        Applicability: Model DHC-7 series airplanes having serial 
    numbers 1 through 99 inclusive, certificated in any category.
        Compliance: Required as indicated, unless accomplished 
    previously.
        To prevent structural failure, accomplish the following:
        (a) For airplanes having serial numbers 1 through 77 inclusive, 
    79 through 83 inclusive, 85, and 86: Within 12 months after the 
    effective date of this AD, inspect the clearance between the wing 
    forward pick-up adapter plates and the seal retaining angle on the 
    fuselage side access panel in accordance with de Havilland Service 
    Bulletin 7-57-11, dated December 17, 1982.
        (1) If the adapter plates are undamaged or if scoring on the 
    adapter plates does not exceed 0.050 inch in depth, prior to further 
    flight, accomplish Modification 7/2319 in accordance with the 
    service bulletin.
        (2) If scoring on the adapter plates is equal to or exceeds 
    0.050 inch in depth, prior to further flight, repair in accordance 
    with a method approved by the Manager, New York Aircraft 
    Certification Office (ACO), ANE-170, FAA, Engine and Propeller 
    Directorate.
        (b) For airplanes having serial numbers 1 through 99 inclusive: 
    Within 12 months after the effective date of this AD, inspect the 
    clearance between the rear mounting adapter plates and the seal 
    retaining angle on the fuselage side access panel in accordance with 
    de Havilland Service Bulletin 7-57-19, dated February 24, 1984.
        (1) If the adapter plates are undamaged or if scoring on the 
    adapter plates does not exceed 0.050 inch in depth, prior to further 
    flight, accomplish Modification 7/2355 in accordance with the 
    service bulletin.
        (2) If scoring on the adapter plates is equal to or exceeds 
    0.050 inch in depth, prior to further flight, repair in accordance 
    with a method approved by the Manager, New York ACO, ANE-170, FAA, 
    Engine and Propeller Directorate.
        (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, New York ACO, ANE-170, FAA, Engine 
    and Propeller Directorate. Operators shall submit their requests 
    through an appropriate FAA Principal Maintenance Inspector, who may 
    add comments and then send it to the Manager, New York ACO.
    
        Note: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the New York ACO.
    
        (d) Special flight permits may be issued in accordance with 
    Federal Aviation Regulations (FAR) 21.197 and 21.199 to operate the 
    airplane to a location where the requirements of this AD can be 
    accomplished.
        (e) The inspections and modifications shall be done in 
    accordance with de Havilland Service Bulletin 7-57-11, dated 
    December 17, 1982, and de Havilland Service Bulletin 7-57-19, dated 
    February 24, 1984. 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 de Havilland, 
    Inc., Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies 
    may be inspected at the FAA, Transport Airplane Directorate, 1601 
    Lind Avenue, SW., Renton, Washington; or at the FAA, Engine and 
    Propeller Directorate, New York Aircraft Certification Office, 181 
    South Franklin Avenue, Room 202, Valley Stream, New York; or at the 
    Office of the Federal Register, 800 North Capitol Street, NW., suite 
    700, Washington, DC.
        (f) This amendment becomes effective on June 6, 1994.
    
        Issued in Renton, Washington, on April 18, 1994.
    Darrell M. Pederson, Acting Manager,
    Transport Airplane Directorate, Aircraft Certification Service.
    [FR Doc. 94-9730 Filed 5-4-94; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
6/6/1994
Published:
05/05/1994
Department:
Transportation Department
Entry Type:
Uncategorized Document
Action:
Final rule.
Document Number:
94-9730
Dates:
Effective June 6, 1994.
Pages:
0-0 (1 pages)
Docket Numbers:
Federal Register: May 5, 1994, Docket No. 92-NM-157-AD, Amendment 39-8893, AD 94-09-05
CFR: (1)
14 CFR 39