97-25607. Airworthiness Directives; American Champion Aircraft Corporation Model 8GCBC Airplanes  

  • [Federal Register Volume 62, Number 187 (Friday, September 26, 1997)]
    [Proposed Rules]
    [Pages 50527-50529]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-25607]
    
    
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    Proposed Rules
                                                    Federal Register
    ________________________________________________________________________
    
    This section of the FEDERAL REGISTER contains notices to the public of 
    the proposed issuance of rules and regulations. The purpose of these 
    notices is to give interested persons an opportunity to participate in 
    the rule making prior to the adoption of the final rules.
    
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    Federal Register / Vol. 62, No. 187 / Friday, September 26, 1997 / 
    Proposed Rules
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 97-CE-37-AD]
    RIN 2120-AA64
    
    
    Airworthiness Directives; American Champion Aircraft Corporation 
    Model 8GCBC Airplanes
    
    agency: Federal Aviation Administration, DOT.
    
    action: Notice of proposed rulemaking (NPRM).
    
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    summary: This document proposes to supersede Airworthiness Directive 
    (AD) 87-18-09, which currently requires inspecting (one-time) the sides 
    of the front and rear wood spars for compression cracks on certain 
    American Champion Aircraft Corporation (ACAC) Model 8GCBC airplanes, 
    and repairing or replacing any wood spar with compression cracks. The 
    proposed AD would require installing inspection holes on the top and 
    bottom wing surfaces, repetitively inspecting the front and rear wood 
    spars for damage, repairing or replacing any damaged wood spar, and 
    installing inspection covers. Damage is defined as cracks; compression 
    cracks; longitudinal cracks through the bolt holes, spacer holes, or 
    nail holes; or loose or missing rib nails. The proposed AD results from 
    in-flight wing structural failure on one of the affected airplanes that 
    was in compliance with the one-time inspection requirement of AD 87-18-
    09. The actions specified by the proposed AD are intended to prevent 
    damage in the wood spar wing from going undetected, which could result 
    in in-flight structural failure of the wing with consequent loss of 
    control of the airplane.
    
    dates: Comments must be received on or before November 28, 1997.
    
    addresses: Submit comments in triplicate to the Federal Aviation 
    Administration (FAA), Central Region, Office of the Assistant Chief 
    Counsel, Attention: Rules Docket No. 97-CE-37-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 and Friday, holidays 
    excepted.
        Service information that applies to the proposed AD may be obtained 
    from American Champion Aircraft Corporation, P.O. Box 37, 32032 
    Washington Avenue, Highway D, Rochester, Wisconsin 53167. This 
    information also may be examined at the Rules Docket at the address 
    above.
    
    for further information contact: Mr. William Rohder, Aerospace 
    Engineer, FAA, Chicago Aircraft Certification Office, 2300 E. Devon 
    Avenue, Des Plaines, Illinois 60018; telephone (847) 294-7697; 
    facsimile (847) 294-7834.
    
    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. 97-CE-37-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 Assistant Chief Counsel, 
    Attention: Rules Docket No. 97-CE-37-AD, Room 1558, 601 E. 12th Street, 
    Kansas City, Missouri 64106.
    
    Discussion
    
        AD 87-18-09, Amendment 39-5725, currently requires inspecting (one-
    time) the sides of the front and rear wood spars for compression cracks 
    on American Champion Aircraft Corporation (ACAC) Model 8GCBC airplanes, 
    repairing or replacing any wood spar with compression cracks, and re-
    inspecting immediately after any incident involving wing damage. AD 87-
    18-09 was the result of three accidents involving ACAC Model 8GCBC 
    airplanes where compression cracks in the wood spar caused in-flight 
    structural failure of the wing.
        Wood compression cracks are failures of wood fibers on a plane 
    perpendicular to the wood fiber longitudinal axis. Repetitive high 
    stress can initiate these compression cracks on the top or bottom 
    surface of the wing spar adjacent to doubler plate glue lines and rib 
    nail holes. These high stress conditions can occur during crop dusting, 
    banner and glider tow operations, turbulence, and rough field or float 
    operations. Compression cracks can also initiate if the wing contacts 
    the ground. Compression cracks can initiate at either the top or bottom 
    surface of the spar depending on the bending loads (either upward or 
    downward) at impact.
    
    Actions Since Issuance of Previous Rule
    
        In-flight structural failure of the wing recently occurred on an 
    ACAC Model 8GCBC airplane that was initially inspected as required by 
    AD 87-18-09. A possible contributing factor of this accident was an 
    undetected compression crack on the right wing front spar.
        Review of data acquired from inspections of several ACAC Model 
    8GCBC airplanes indicate that wood spar compression cracks can occur 
    without previous wing damage. The data indicates that detection of a 
    compression crack on the sides of the spar is unlikely, unless the 
    crack is in an advanced state of propagation. Based
    
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    on this data, the FAA believes that repetitive inspections are 
    necessary.
    
    Relevant Service Information
    
        The FAA has reviewed and approved the technical contents of ACAC 
    Service Letter 406, dated March 28, 1994, and ACAC Service Letter 417, 
    dated August 14, 1997. ACAC Service Letter 406 includes procedures for 
    conducting a detailed visual inspection of both the front and rear wood 
    wing spars for cracks; compression cracks; longitudinal cracks through 
    the bolt holes, spacer holes, or nail holes; and loose or missing rib 
    nails (referred to as damage hereon). ACAC Service Letter 417 includes 
    procedures for installing inspection holes and surface covers and 
    assuring that all applicable lower surface drain holes are installed.
    
    The FAA's Determination
    
        After examining the circumstances and reviewing all available 
    information related to the incidents and accidents described above, 
    including the referenced service information, the FAA has determined 
    that AD action should be taken to prevent damage in the wood spar from 
    going undetected, which could result in in-flight structural failure of 
    the wing with consequent loss of control of the airplane.
    
    Explanation of the Provisions of the Proposed AD
    
        Since an unsafe condition has been identified that is likely to 
    exist or develop in other ACAC Model 8GCBC airplanes of the same type 
    design, the FAA is proposing an AD to supersede AD 87-18-09. The 
    proposed AD would require installing inspection holes on the top and 
    bottom wing surfaces, repetitively inspecting the front and rear wood 
    spars for damage, repairing or replacing any damaged wood spar, and 
    installing surface covers.
        Accomplishment of the proposed actions would be as follows:
    
    --Installations: in accordance with ACAC Service Letter 417, dated 
    August 14, 1997;
    --Inspections: in accordance with ACAC Service Letter 406, dated March 
    28, 1994; and
    --Spar Repair and Replacement, as applicable: in accordance with 
    Advisory Circular (AC) 43-13, Acceptable Methods, Techniques and 
    Practices; or other data that the FAA has approved for spar repair and 
    replacement
    
    Difference Between This Proposed AD and ACAC Service Letter 406
    
        ACAC Service Letter 406, dated March 28, 1994, specifies the same 
    inspections as are proposed in this notice of proposed rulemaking 
    (NPRM). The differences between the service letter and NPRM are:
    
    --The service letter specifies the proposed action within the next 30 
    days or 10 flight hours and at each 100 hour/annual inspection 
    thereafter. The FAA has determined that a more realistic compliance and 
    enforceable compliance time would be to require the proposed action 
    within 3 calendar months after the effective date of the AD, and 
    thereafter at intervals not to exceed 12 calendar months or 500 hours 
    time-in-service (TIS), whichever occurs first; and
    --The service letter applies to all ACAC 7 and 8 series airplanes, 
    whereas the NPRM applies only to ACAC Model 8GCBC airplanes. The FAA is 
    currently reviewing the service history of all of the ACAC airplane 
    models specified in ACAC Service Letter 406. Based on this review, the 
    FAA may initiate additional rulemaking action in the future on the 
    airplane models other than the Model 8GCBC airplanes. This potential 
    action may propose the same actions as the proposed AD with either the 
    same or different compliance times, or may propose entirely different 
    actions altogether.
    
    Compliance Time of the Proposed AD
    
        The compliance time of the proposed AD is presented in calendar 
    time and hours TIS. Although the unsafe condition specified in the 
    proposed AD is a result of airplane operation, operators of the 
    affected airplanes utilize their airplanes in different ways.
        For example, an operator may utilize his/her airplane 50 hours TIS 
    in a year while utilizing the aircraft in no or very little crop 
    dusting operations, banner and glider tow operations, or rough field or 
    float operations. This airplane operator would obviously experience 
    less of a chance of high crack propagation than the airplane operator 
    that utilizes his/her airplane 300 hours TIS in a year regularly in 
    heavy crop dusting operations, banner and glider tow operations, or 
    rough field or float operations. However, this airplane could have pre-
    existing and undetected wood spar damage that occurred during previous 
    operations. In this situation, the damage to the wood spar would 
    propagate at a level that depends on the operational exposure of the 
    airplane and severity of the wood spar damage.
        To assure that compression cracks do not go undetected on the wood 
    spars of the affected airplanes, the FAA has determined that an initial 
    3 calendar month compliance time should be used. Repetitive actions 
    would be accomplished every 12 calendar months or 500 hours TIS, 
    whichever occurs first.
    
    Cost Impact
    
        The FAA estimates that 261 airplanes in the U.S. registry would be 
    affected by the proposed AD, that it would take approximately 6 
    workhours (Installations: 5 workhours; Initial Inspection: 1 workhour) 
    per airplane to accomplish the proposed action, and that the average 
    labor rate is approximately $60 an hour. Parts cost approximately $292 
    per airplane, provided that each airplane would only need 11 additional 
    standard inspection hole covers per wing (total of 22 additional 
    standard covers per airplane). If the airplane would require the 
    installation of more inspection covers (i.e., a result of previous non-
    factory wing recover work), the cost could be slightly higher. Based on 
    these figures, the total cost impact of the proposed AD on U.S. 
    operators is estimated to be $170,172 or $652 per airplane.
        This cost figure is based on the presumption that no affected 
    airplane owner/operator has accomplished the installations or the 
    initial inspection. The FAA has no knowledge of any owner/operator of 
    the affected airplanes that has already accomplished the installations 
    and initial inspection.
        The cost figure also does not account for repetitive inspections. 
    The FAA has no way of determining the number of repetitive inspections 
    each owner/operator of the affected airplanes will incur over the life 
    of his/her airplane. However, each proposed repetitive inspection would 
    cost substantially less than the initial inspection because of the cost 
    of the initial proposed inspection hole and cover installations. The 
    inspection covers allow easy access for the inspection of the wood 
    spars, and the proposed compliance time would enable the owners/
    operators of the affected airplanes to accomplish the repetitive 
    inspections at regularly scheduled annual inspections.
    
    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.
    
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        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 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 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. 106(g), 40113, 44701.
    
    
    Sec. 39.13  [Amended]
    
        2. Section 39.13 is amended by removing Airworthiness Directive 
    (AD) 87-18-09, Amendment 39-5725, and by adding a new AD to read as 
    follows:
    
    American Champion Aircraft Company: Docket No. 97-CE-37-AD; 
    Supersedes AD 87-18-09, Amendment 39-5725.
    
        Applicability: Model 8GCBC airplanes, all serial numbers, 
    certificated in any category, that are equipped with wood wing 
    spars.
    
        Note 1: This AD applies to each airplane identified in the 
    preceding applicability provision, regardless of whether it has been 
    modified, altered, repaired, or reconfigured in the area subject to 
    the requirements of this AD. For airplanes that have been modified, 
    altered, repaired, or reconfigured 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 (e) 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 damage in the wood spar wing from going undetected, 
    which could result in in-flight structural failure of the wing with 
    consequent loss of control of the airplane, accomplish the 
    following:
        (a) Within the next 3 calendar months after the effective date 
    of this AD, accomplish the following:
        (1) Install inspection holes in the top and bottom surface of 
    each wing in accordance with American Champion Aircraft Corporation 
    (ACAC) Service Letter 417, dated August 14, 1997. Assure that all 
    drainage holes are installed as depicted in this service letter, and 
    install drainage holes as necessary.
        (2) Inspected (detailed visual) both the front and rear wood 
    wing spars for cracks; compression cracks; longitudinal cracks 
    through the bolt holes, spacer holes, or nail holes; and loose or 
    missing rib nails (referred to as damage hereon). Accomplish these 
    inspections in accordance with ACAC Service Letter 406, dated March 
    28, 1994.
        (3) If any spar damage is found, prior to further flight, 
    accomplish the following:
        (i) Repair or replace the wood wing spar in accordance with 
    Advisory Circular (AC) 43-13, Acceptable Methods, Techniques and 
    Practices; or other data that is approved by the FAA for wing spar 
    repair or replacement.
        (ii) If the wing is recovered, accomplish the installations 
    required by paragraph (a)(1) of this AD, as applicable.
        (4) Install inspection hole covers on the top and bottom surface 
    of the wing in accordance with ACAC Service Letter 417, dated August 
    14, 1997.
        (b) Within 12 calendar months or 500 hours TIS (whichever occurs 
    first) after accomplishing all actions required by paragraph (a), 
    all subparagraphs included, of this AD, and thereafter at intervals 
    not to exceed 12 calendar months or 500 hours TIS, whichever occurs 
    first, accomplish the inspection, repair, replacement, and 
    installation required by paragraphs (a)(2), (a)(3) as applicable; 
    including its subparagraphs; and (a)(4) of this AD.
    
        Note 2: The affected airplanes are not certificated for 
    acrobatic maneuvers. AD 87-18-09 required a placard prohibiting 
    acrobatic maneuvers in addition to the existing operational placard. 
    The FAA encourages owners/operators of the affected airplanes to 
    keep this placard installed on their airplanes.
    
        (c) If any of the affected airplanes are involved in an incident 
    involving wing damage after the effective date of this AD, prior to 
    further flight, accomplish the inspection, repair, replacement, and 
    installation required by paragraphs (a)(2), (a)(3), as applicable; 
    including its subparagraphs; and (a)(4) of this AD.
        (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) An alternative method of compliance or adjustment of the 
    initial or repetitive compliance time that provides an equivalent 
    level of safety may be approved by the Manager, Chicago Aircraft 
    Certification Office (ACO), 2300 E. Devon Avenue, Des Plaines, 
    Illinois 60018.
        (1) The request shall be forwarded through an appropriate FAA 
    Maintenance Inspector, who may add comments and then send it to the 
    Manager, Chicago ACO.
        (2) Alternative methods of compliance approved in accordance 
    with AD 87-18-09 (superseded by this action) are not considered 
    approved as alternative methods of compliance for this AD.
    
        Note 3: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the Chicago ACO.
    
        (f) All persons affected by this directive may obtain copies of 
    the documents referred to herein upon request to American Champion 
    Aircraft Corporation, P.O. Box 37, 32032 Washington Avenue, Highway 
    D, Rochester, Wisconsin 53167; or may examine these documents at the 
    FAA, Central Region, Office of the Assistant Chief Counsel, Room 
    1558, 601 E. 12th Street, Kansas City, Missouri 64106.
        (g) This amendment supersedes AD 87-18-09, Amendment 39-5725.
    
        Issued in Kansas City, Missouri, on September 22, 1997.
    Henry A. Armstrong,
    Acting Manager, Small Airplane Directorate, Aircraft Certification 
    Service.
    [FR Doc. 97-25607 Filed 9-25-97; 8:45 am]
    BILLING CODE 4910-13-M
    
    
    

Document Information

Published:
09/26/1997
Department:
Federal Aviation Administration
Entry Type:
Proposed Rule
Action:
Notice of proposed rulemaking (NPRM).
Document Number:
97-25607
Dates:
Comments must be received on or before November 28, 1997.
Pages:
50527-50529 (3 pages)
Docket Numbers:
Docket No. 97-CE-37-AD
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
97-25607.pdf
CFR: (1)
14 CFR 39.13