97-17533. Airworthiness Directives; Air Tractor Incorporated Models AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 Airplanes  

  • [Federal Register Volume 62, Number 138 (Friday, July 18, 1997)]
    [Rules and Regulations]
    [Pages 38445-38447]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-17533]
    
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 96-CE-47-AD; Amendment 39-10063; AD 97-14-05]
    RIN 2120-AA64
    
    
    Airworthiness Directives; Air Tractor Incorporated Models AT-301, 
    AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 Airplanes
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule.
    
    -----------------------------------------------------------------------
    
    SUMMARY: This amendment supersedes Airworthiness Directive AD 95-20-06, 
    which applies to certain Air Tractor Incorporated (Air Tractor) Models 
    AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 
    airplanes and currently requires repetitively inspecting the front spar 
    attachment lugs and the rear spar for fatigue cracks, and modifying the 
    vertical fin if cracks are found. The modification terminates the 
    repetitive inspection requirement of AD 95-20-06 and may be 
    incorporated at any time, if cracks are not found. The FAA has 
    determined that the Air Tractor Models mentioned above with a \1/4\-
    inch fin front spar fitting installed should be exempt from the AD. The 
    AD will retain the requirements of AD 95-20-06 for all Air Tractor 
    airplanes that have a \3/16\-inch fin front spar fitting. The actions 
    specified by this AD are intended to prevent in-flight vertical fin 
    cracking, which, if not detected and corrected, could result in 
    structural failure of the front spar attachments and eventually the 
    rear spar attachment and cause loss of directional control of the 
    airplane.
    
    DATES: Effective August 25, 1997.
    
        The incorporation by reference of certain publications listed in 
    the regulations is approved by the Director of the Federal Register as 
    of August 25, 1997.
    
    ADDRESSES: Service information that applies to this AD may be obtained 
    from Air Tractor Incorporated, P. O. Box 485, Olney, Texas 76374. This 
    information may also be examined at the Federal Aviation Administration 
    (FAA), Central Region, Office of the Assistant Chief Counsel, 
    Attention: Rules Docket 96-CE-47-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: Bob May, Aerospace Engineer, FAA, Fort 
    Worth Airplane Certification Office, 2601 Meacham Boulevard, Fort 
    Worth, Texas 76193-0150; telephone (817) 222-5156; facsimile (817) 222-
    5960.
    
    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 Air Tractor airplanes 
    fitted with \3/16\-inch thick front spar attachment fittings that do 
    not have the modification in Snow Engineering Company Report No. 138, 
    dated July 29, 1995, Revised August 7, 1996, included the following 
    Models and serial numbers:
    
    ------------------------------------------------------------------------
                     Models                           Serial numbers        
    ------------------------------------------------------------------------
    AT-301 and AT-401......................  301-0261 through 301-0736, and 
                                              401-0662 through 401-0736 that
                                              have been converted to turbine
                                              powerplants and equipped with 
                                              the all metal rudder, part    
                                              number (P/N) 30456-1.         
    AT-302.................................  All aircraft equipped with the 
                                              all metal rudder, P/N 30456-1.
    AT-400 and AT-400A.....................  All aircraft equipped with the 
                                              all metal rudder, P/N 30456-1.
    AT-402.................................  402-0694, and 402-0695 through 
                                              402-0736.                     
    AT-501.................................  501-0002 through 501-0030 that 
                                              have been converted to turbine
                                              powerplants and equipped with 
                                              the all metal rudder, P/N     
                                              30456-1.                      
    AT-502.................................  502-0002 through 502-0030.     
    ------------------------------------------------------------------------
    
    The notice of proposed rulemaking (NPRM) for this action was published 
    in the Federal Register on February 19, 1997 (62 FR 7377). The proposed 
    AD would supersede AD 95-20-06 with a new AD that would require 
    inspecting the fin front spar attachment fittings of Models that have 
    \3/16\-inch thick fin front spar attachment fittings for cracks, and if 
    cracks are found, prior to further flight, modifying the front spar 
    attachment fittings. If no cracks are
    
    [[Page 38446]]
    
    found, the proposed AD would require repetitively inspecting the front 
    spar attachment fittings until cracks are found. Accomplishing the 
    modification upon finding cracks or at any time prior to finding cracks 
    would terminate the repetitive inspections.
        Accomplishment of the proposed action would be in accordance with 
    Snow Engineering Report (SER) number (No.) 138, dated July 29, 1995, 
    Revised August 7, 1996.
        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.
    
    Cost Impact
    
        The FAA estimates that 24 airplanes in the U.S. registry will be 
    affected by this AD, that it will take approximately 16 workhours per 
    airplane to accomplish this action, and that the average labor rate is 
    approximately $60 an hour. Parts cost approximately $10 per airplane. 
    Based on these figures, the total cost impact of this AD on U.S. 
    operators is estimated to be $23,280 or $970 per airplane. This figure 
    is based on the presumption that no owner/operator of the affected 
    airplanes has accomplished the required actions.
    
    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 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 USC 106(g), 40113, 44701.
    
    
    Sec. 39.13  [Amended]
    
        2. Section 39.13 is amended by removing airworthiness directive 
    (AD) 95-20-06, Amendment No. 39-9384 (60 FR 52620) and by adding a new 
    AD to read as follows:
    
    97-14-05. Air Tractor Incorporated: Amendment No. 39-10063; Docket 
    No. 96-CE-47-AD; Supersedes AD 95-20-06, Amendment 39-9384. 
    Applicability: The following airplane Models and serial numbers 
    fitted with a \3/16\-inch fin front spar fitting that do not have 
    the modification in Snow Engineering Company Report No. 138, dated 
    July 29, 1995, revised August 7, 1996, incorporated, certificated in 
    any category:
    
        Note 1: The modification in Snow Engineering Company Report No. 
    138, dated July 29, 1995, revised August 7, 1996, and AD 95-20-06 
    required the airplanes to replace 3/16-inch thick fin front spar 
    attach fittings with \1/4\-inch thick fin front spar attach 
    fittings.
    
    ------------------------------------------------------------------------
                     Models                           Serial numbers        
    ------------------------------------------------------------------------
    AT-301 and AT-401......................  301-0261 through 301-0736, and 
                                              401-0662 through 401-0736 that
                                              have been converted to turbine
                                              powerplants and equipped with 
                                              the all metal rudder, part    
                                              number (P/N) 30456-1.         
    AT-302.................................  All aircraft equipped with the 
                                              all metal rudder, P/N 30456-1.
    AT-400 and AT-400A.....................  All aircraft equipped with the 
                                              all metal rudder, P/N 30456-1.
    AT-402.................................  402-0694 and 402-0695 through  
                                              402-0736.                     
    AT-501.................................  501-0002 through 501-0030 that 
                                              have been converted to turbine
                                              powerplants and equipped with 
                                              the all metal rudder, P/N     
                                              30456-1.                      
    AT-502.................................  AT-502 502-0002 through 502-   
                                              0030.                         
    ------------------------------------------------------------------------
    
        Note 2: 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 (f) 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 initially within the next 25 hours time-in-
    service (TIS) after the effective date of this AD, unless already 
    accomplished, and thereafter as indicated in the body of this AD.
        To prevent in-flight vertical fin cracking, which, if not 
    detected and corrected, could result in structural failure of the 
    front spar attachments and eventually the rear spar attachment and 
    cause loss of directional control of the airplane, accomplish the 
    following:
        (a) Inspect the fin front spar attachment fittings for fatigue 
    cracks in accordance with the INSTRUCTIONS section of the Snow 
    Engineering Report (SER) number (No.) 138, dated July 29, 1995, 
    Revised August 7, 1996.
        (b) If no cracks are found during the initial inspection, repeat 
    the inspection required by paragraph (a) of this AD at intervals not 
    to exceed 25 hours TIS thereafter in accordance with the 
    INSTRUCTIONS section of the SER No. 138, Revised August 7, 1996.
        (c) If cracks are found during any inspections required by this 
    AD, prior to further flight, modify the fin front spar attachment 
    fittings in accordance with the
    
    [[Page 38447]]
    
    INSTRUCTIONS section of the SER No. 138, dated July 29, 1995, 
    Revised August 7, 1996.
        (d) Incorporating the modification specified in paragraph (c) of 
    this AD is considered terminating action for the repetitive 
    inspection requirements of this AD.
        (e) 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.
        (f) An alternative method of compliance or adjustment of the 
    compliance times that provides an equivalent level of safety may be 
    approved by the Manager, Fort Worth Airplane Certification Office, 
    2601 Meacham Boulevard, Fort Worth, Texas 76193-0150. The request 
    shall be forwarded through an appropriate FAA Maintenance Inspector, 
    who may add comments and then send it to the Manager, Fort Worth 
    Airplane Certification Office.
    
        Note 3: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from Fort Worth Airplane Certification Office.
    
        (g) The inspection and modification required by this AD shall be 
    done in accordance with Snow Engineering Report No. 138, dated July 
    29, 1995, Revised August 7, 1996. 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 
    Air Tractor Incorporated, P.O. Box 485, Olney, Texas 76374. Copies 
    may be inspected at the FAA, Central Region, Office of the Assistant 
    Chief 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.
        (h) This amendment supersedes AD 95-20-06, Amendment 39-9384.
        (i) This amendment (39-10063) becomes effective on August 25, 
    1997.
    
        Issued in Kansas City, Missouri, on June 26, 1997.
    James E. Jackson,
    Acting Manager, Small Airplane Directorate, Aircraft Certification 
    Service.
    [FR Doc. 97-17533 Filed 7-17-97; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
8/25/1997
Published:
07/18/1997
Department:
Federal Aviation Administration
Entry Type:
Rule
Action:
Final rule.
Document Number:
97-17533
Dates:
Effective August 25, 1997.
Pages:
38445-38447 (3 pages)
Docket Numbers:
Docket No. 96-CE-47-AD, Amendment 39-10063, AD 97-14-05
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
97-17533.pdf
CFR: (1)
14 CFR 39.13