96-11958. Airworthiness Directives; Bell Helicopter Textron, Inc. Model 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47-K Helicopters  

  • [Federal Register Volume 61, Number 94 (Tuesday, May 14, 1996)]
    [Rules and Regulations]
    [Pages 24218-24220]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 96-11958]
    
    
    
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    DEPARTMENT OF TRANSPORTATION
    14 CFR Part 39
    
    [Docket No. 96-SW-01-AD; Amendment 39-9616; AD 96-06-12]
    RIN 2120-AA64
    
    
    Airworthiness Directives; Bell Helicopter Textron, Inc. Model 
    47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 
    47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 
    47J, 47J-2, 47J-2A, and 47-K Helicopters
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule; request for comments.
    
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    SUMMARY: This document publishes in the Federal Register an amendment 
    adopting Airworthiness Directive (AD) 96-06-12 which was sent 
    previously to all known U.S. owners and operators of Bell Helicopter 
    Textron, Inc. (Bell) Model 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 
    47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 
    47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47-K helicopters by 
    individual letters. This AD requires a visual inspection of each tail 
    rotor blade (blade) tip, abrasion strip, blade skin, and blade butt for 
    corrosion or delamination. This amendment is prompted by reports that a 
    number of Model 47 helicopter blades were manufactured using a clad 
    aluminum alloy material instead of a bare aluminum alloy material. The 
    actions specified by this AD are intended to prevent premature 
    delamination or separation of the blade tip block or the abrasion 
    strip, which could lead to failure of the blade and subsequent loss of 
    control of the helicopter.
    
    
    [[Page 24219]]
    
    
    DATES: Effective May 29, 1996, to all persons except those persons to 
    whom it was made immediately effective by priority letter AD 96-06-12, 
    issued on March 13, 1996, which contained the requirements of this 
    amendment.
        Comments for inclusion in the Rules Docket must be received on or 
    before July 15, 1996.
    
    ADDRESSES: Submit comments in triplicate to the Federal Aviation 
    Administration (FAA), Office of the Assistant Chief Counsel, Attention: 
    Rules Docket No. 96-SW-01-AD, 2601 Meacham Blvd., Room 663, Fort Worth, 
    Texas 76137.
    
    FOR FURTHER INFORMATION CONTACT: Mr. Tony Nguyen, Aerospace Engineer, 
    Rotorcraft Certification Office, Rotorcraft Directorate, FAA, 2601 
    Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5177; fax 
    (817) 222-5960.
    
    SUPPLEMENTARY INFORMATION: On March 13, 1996, the FAA issued priority 
    letter AD 96-06-12, applicable to Bell Model 47B, 47B-3, 47D, 47D-1, 
    47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-
    3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47-
    K helicopters, which requires, prior to the first flight of each day, 
    and at intervals not to exceed 10 hours time-in-service (TIS) if the 
    helicopter is operated for more than 10 hours in any one day, a visual 
    inspection of each blade tip, abrasion strip, blade skin, and blade 
    butt for corrosion or delamination. That action was prompted by reports 
    that a number of Model 47 helicopter blades were manufactured using a 
    clad aluminum alloy material instead of a bare aluminum alloy material. 
    The shear and peel strength of bonded clad aluminum alloy is less than 
    the shear and peel strength of bonded bare aluminum alloy. This 
    condition, if not corrected, could result in premature delamination or 
    separation of the blade tip block or the abrasion strip, which could 
    lead to failure of the blade and subsequent loss of control of the 
    helicopter.
        Since the unsafe condition described is likely to exist or develop 
    on other Bell Model 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 47G-2A-
    1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 
    47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47-K helicopters of the same 
    type design, the FAA issued priority letter AD 96-06-12 to prevent 
    premature delamination or separation of the blade tip block or the 
    abrasion strip, which could lead to failure of the blade and subsequent 
    loss of control of the helicopter. The AD requires, prior to the first 
    flight of each day, and at intervals not to exceed 10 hours TIS, if the 
    helicopter is operated for more than 10 hours in any one day, a visual 
    inspection of each blade tip, abrasion strip, blade skin, and blade 
    butt for corrosion or delamination. If any of the inspections reveal 
    corrosion or delamination, removal of the blades and replacement with 
    airworthy blades is required.
        Since it was found that immediate corrective action was required, 
    notice and opportunity for prior public comment thereon were 
    impracticable and contrary to the public interest, and good cause 
    existed to make the AD effective immediately by individual letters 
    issued on March 13, 1996 to all known U.S. owners and operators of Bell 
    Model 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3, 47G-
    3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-4A, 47G-5, 47G-5A, 47H-1, 
    47J, 47J-2, 47J-2A, and 47-K helicopters. These conditions still exist, 
    and the AD is hereby published in the Federal Register as an amendment 
    to section 39.13 of the Federal Aviation Regulations (14 CFR 39.13) to 
    make it effective to all persons.
    
    Comments Invited
    
        Although this action is in the form of a final rule that involves 
    requirements affecting flight safety and, thus, was not preceded by 
    notice and an opportunity for public comment, comments are invited on 
    this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
    communications received on or before the closing date for comments will 
    be considered, and this rule may be amended in light of the comments 
    received. Factual information that supports the commenter's ideas and 
    suggestions is extremely helpful in evaluating the effectiveness of the 
    AD action and determining whether additional rulemaking action would be 
    needed.
        Comments are specifically invited on the overall regulatory, 
    economic, environmental, and energy aspects of the rule that might 
    suggest a need to modify the 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 
    AD will be filed in the Rules Docket.
        Commenters wishing the FAA to acknowledge receipt of their comments 
    submitted in response to this rule must submit a self-addressed, 
    stamped postcard on which the following statement is made: ``Comments 
    to Docket No. 96-SW-01-AD.'' The postcard will be date stamped and 
    returned to the commenter.
        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.
        The FAA has determined that this regulation is an emergency 
    regulation that must be issued immediately to correct an unsafe 
    condition in aircraft, and that it is not a ``significant regulatory 
    action'' under Executive Order 12866. It has been determined further 
    that this action involves an emergency regulation under DOT Regulatory 
    Policies and Procedures (44 FR 11034, February 26, 1979). If it is 
    determined that this emergency regulation otherwise would be 
    significant under DOT Regulatory Policies and Procedures, a final 
    regulatory evaluation will be prepared and placed in the Rules Docket. 
    A copy of it, if filed, 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, 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.
    
    [[Page 24220]]
    
    Sec. 39.13  [Amended]
    
        2. Section 39.13 is amended by adding a new airworthiness directive 
    to read as follows:
    
    AD 96-06-12  Bell Helicopter Textron, Inc.: Amendment 39-9616. 
    Docket No. 96-SW-01-AD.
    
        Applicability: Model 47B, 47B-3, 47D, 47D-1, 47G, 47G-2, 47G-2A, 
    47G-2A-1, 47G-3, 47G-3B, 47G-3B-1, 47G-3B-2, 47G-3B-2A, 47G-4, 47G-
    4A, 47G-5, 47G-5A, 47H-1, 47J, 47J-2, 47J-2A, and 47-K helicopters, 
    with tail rotor blade assembly, part number (P/N) 047-642-117-105, 
    serial numbers (S/N) A-1943 through A-2068, installed, certificated 
    in any category.
    
        Note 1: This AD applies to each helicopter 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 helicopters that have been modified, 
    altered, or repaired so that the performance of the requirements of 
    this AD is affected, the owner/operator must use the authority 
    provided in paragraph (f) to request approval from the FAA. This 
    approval may address either no action, if the current configuration 
    eliminates the unsafe condition, or different actions necessary to 
    address the unsafe condition described in this AD. Such a request 
    should include an assessment of the effect of the changed 
    configuration on the unsafe condition addressed by this AD. In no 
    case does the presence of any modification, alteration, or repair 
    remove any helicopter from the applicability of this AD.
    
        Compliance: Required as indicated, unless accomplished 
    previously.
        To prevent premature delamination or separation of the tail 
    rotor blade (blade) tip block or the abrasion strip, which could 
    lead to failure of the blade and subsequent loss of control of the 
    helicopter, accomplish the following:
        (a) Prior to the first flight of each day, visually inspect each 
    blade tip, abrasion strip, blade skin and blade butt as follows:
        (1) Inspect each blade tip for corrosion or delamination 
    adjacent to the abrasion strip and tip block.
        (2) Inspect each abrasion strip for corrosion or delamination, 
    paying particular attention to the abrasion strip leading edge.
        (3) Inspect each blade skin for corrosion, paying particular 
    attention to any areas of paint cracking or damage. Inspect all 
    bonded joints for corrosion or delamination.
        (4) Inspect each blade butt around the bearings for corrosion or 
    delamination.
        (b) Thereafter, conduct the visual inspections specified in 
    paragraph (a) of this AD at intervals not to exceed 10 hours time-
    in-service.
        (c) If the inspections required by paragraphs (a) and (b) of 
    this AD reveal any corrosion or delamination, replace the blade with 
    an airworthy blade before further flight.
        (d) Installation of any airworthy tail rotor blade assembly 
    which has been FAA-approved for the particular Model 47 helicopter, 
    except for P/N 047-642-117-105 with S/N A-1943 through A-2068, 
    constitutes a terminating action for the requirements of this AD.
        (e) Installation of tail rotor blade assembly, P/N 047-642-117-
    105M, including those with S/N A-1943 through A-2068, constitutes a 
    terminating action for the requirements of this AD.
    
        Note 2: Bell Helicopter Textron Alert Service Bulletin No. 47-
    96-21, dated January 29, 1996, pertains to this AD.
    
        (f) 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, Rotorcraft Certification Office, 
    Rotorcraft Directorate. Operators shall submit their requests 
    through an FAA Principal Maintenance Inspector, who may concur or 
    comment and then send it to the Manager, Rotorcraft Certification 
    Office.
    
        Note 3: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the Rotorcraft Certification Office.
    
        (g) 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 helicopter to a location where 
    the requirements of this AD can be accomplished.
        (h) This amendment becomes effective on May 29, 1996, to all 
    persons except those persons to whom it was made immediately 
    effective by Priority Letter AD 96-06-12, issued March 13, 1996, 
    which contained the requirements of this amendment.
    
        Issued in Fort Worth, Texas, on May 3, 1996.
    Eric Bries,
    Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
    [FR Doc. 96-11958 Filed 5-13-96; 8:45 am]
    BILLING CODE 4910-13-U
    
    

Document Information

Effective Date:
5/29/1996
Published:
05/14/1996
Department:
Transportation Department
Entry Type:
Rule
Action:
Final rule; request for comments.
Document Number:
96-11958
Dates:
Effective May 29, 1996, to all persons except those persons to whom it was made immediately effective by priority letter AD 96-06-12, issued on March 13, 1996, which contained the requirements of this amendment.
Pages:
24218-24220 (3 pages)
Docket Numbers:
Docket No. 96-SW-01-AD, Amendment 39-9616, AD 96-06-12
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
96-11958.pdf
CFR: (1)
14 CFR 39.13