97-16568. Airworthiness Directives; McDonnell Douglas Helicopter Systems Model MD-900 Helicopters  

  • [Federal Register Volume 62, Number 122 (Wednesday, June 25, 1997)]
    [Rules and Regulations]
    [Pages 34163-34165]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-16568]
    
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 96-SW-35-AD; Amendment 39-10056; AD 97-13-09]
    RIN 2120-AA64
    
    
    Airworthiness Directives; McDonnell Douglas Helicopter Systems 
    Model MD-900 Helicopters
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule; request for comments.
    
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    SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
    is applicable to McDonnell Douglas Helicopter Systems (MDHS) Model MD-
    900 helicopters. This action requires applying specified serial numbers 
    to the left and right vertical stabilizer control system (VSCS) 
    bellcrank assemblies, the forward and aft deck-fitting assemblies, and 
    the mid-forward and mid-aft truss strut assemblies; and establishes new 
    life limits for the non-rotating swashplate assembly, the collective 
    drive link assembly, and the self-aligning, spherical/slider main rotor 
    bearing. This amendment is prompted by additional manufacturer's 
    analysis which indicates a need for the reduction of the life limit on 
    several parts and the addition of non-serialized parts to the life-
    limited parts list. The actions specified in this AD are intended to 
    establish a life limit for various parts and reduce the current life 
    limit on other parts.
    
    DATES: Effective July 10, 1997.
        The incorporation by reference of certain publications listed in 
    the regulations is approved by the Director of the Federal Register as 
    of July 10, 1997.
        Comments for inclusion in the rules docket must be received on or 
    before August 25, 1997.
    
    ADDRESSES: Submit comments in triplicate to the Federal Aviation 
    Administration (FAA), Office of the Assistant Chief Counsel, Attention: 
    Rules Docket No. 96-SW-35-AD, 2601 Meacham Blvd., Room 663, Fort Worth, 
    Texas 76137.
    
    [[Page 34164]]
    
        The service information referenced in this AD may be obtained from 
    McDonnell Douglas Helicopter Systems, Technical Publications, Bldg. 
    530/B11, 5000 E. McDowell Road, Mesa, Arizona 85205-9797. This 
    information may be examined at the FAA, Office of the Assistant Chief 
    Counsel, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137; or at 
    the Office of the Federal Register, 800 North Capitol Street, NW., 
    suite 700, Washington, DC.
    
    FOR FURTHER INFORMATION CONTACT: Mr. Greg DiLibero, Aerospace Engineer, 
    Airframe Branch, Los Angeles Aircraft Certification Office, FAA, 3960 
    Paramount Boulevard, Lakewood, California 90712, telephone (562) 627-
    5231, fax (562) 627-5210.
    
    SUPPLEMENTARY INFORMATION: This amendment adopts a new AD that is 
    applicable to MDHS Model MD-900 helicopters. For Model MD-900 
    helicopters with serial numbers (S/N) 0002 through 0012, this action 
    requires applying serial numbers to the mid-forward truss assembly, 
    part number (P/N) 900F2401200-102, and the forward and aft deck-fitting 
    assemblies, P/N 900F2401500-103 and P/N 900F2401600-103. For Model MD-
    900 helicopters with S/N 0002 through 0048, this action requires 
    applying S/N's to the VSCS bellcrank assemblies, part number (P/N) 
    900F2341712-101 or P/N 900FP341712-103, and the mid-aft truss strut 
    assembly, P/N 900F2401300-103. For all Model MD-900 helicopters, this 
    action reduces the life limits for the non-rotating swashplate 
    assembly, P/N 900C2010192-105, -107, -109, or -111, from 8,300 hours 
    time-in-service (TIS) to 554 hours TIS; the collective drive link 
    assembly, P/N 900C2010207-101, from 3,900 hours TIS to 1,480 hours TIS; 
    the self-aligning, spherical/slider main rotor bearing, P/N 
    900C3010042-103, from 2,100 hours TIS to 480 hours TIS; and the VSCS 
    bellcrank assembly, P/N 900FP341712-103, and bellcrank arm, P/N 
    900F2341713-101, (used in the VSCS bellcrank assembly, P/N 900F2341712-
    101) from no life limit to 2,700 hours TIS. This amendment is prompted 
    by additional manufacturer's analysis which indicates a need for the 
    reduction of the life limit on several parts and the addition of non-
    serialized parts to the life-limited parts list. The actions specified 
    in this AD are intended to establish a life limit for various parts and 
    reduce the current life limit on other parts.
        The FAA has reviewed McDonnell Douglas Helicopter Systems Service 
    Bulletin No. SB900-039, Revision 2, dated March 12, 1997, which 
    describes procedures for applying the serial numbers to the life-
    limited parts.
        Since an unsafe condition has been identified that is likely to 
    exist or develop on other MDHS Model MD-900 helicopters of the same 
    type design, this AD is being issued to establish a life limit for 
    various parts and reduce the current life limit on other parts. This AD 
    requires applying specified serial numbers to the left and right VSCS 
    bellcrank assemblies, P/N 900F2341712-101 or P/N 900FP341712-103; to 
    the mid-forward and mid-aft truss strut assemblies, P/N 900F2401200-102 
    and P/N 900F2401300-103; and to the forward and aft deck-fitting 
    assemblies, P/N 900F2401500-103 and P/N 900F2401600-103. This AD also 
    reduces the life limits for the non-rotating swashplate assembly, P/N 
    900C2010192-105, -107, -109, or -111, from 8,300 hours TIS to 554 hours 
    TIS; the collective drive link assembly, P/N 900C2010207-101, from 
    3,900 hours TIS to 1,480 hours TIS; the self-aligning, spherical/slider 
    main rotor bearing, P/N 900C3010042-103, from 2,100 hours TIS to 480 
    hours TIS; and the VSCS bellcrank assembly, P/N 900FP341712-103, and 
    the bellcrank arm, P/N 900F2341713-101, (used in the VSCS bellcrank 
    assembly, P/N 900F2341712-101) from no life limit to 2,700 hours TIS. 
    The serial numbers for the VSCS bellcrank assemblies, the mid-forward 
    and mid-aft truss assemblies, and the forward and aft deck-fitting 
    assemblies are specified in and are required to be accomplished in 
    accordance with the service bulletin described previously. The serial 
    numbers specified in the service bulletin shall be applied adjacent to 
    the existing P/N's. Some Model MD-900 helicopters that are currently in 
    service are equipped with helicopter control system parts that are 
    approaching the new, lower life limits. Failure of any of these parts 
    could result in loss of control of the helicopter. Due to the 
    criticality of the components of the helicopter control system, this AD 
    is being issued in the form of an immediately-adopted final rule with 
    request for comments.
        Since a situation exists that requires the immediate adoption of 
    this regulation, it is found that notice and opportunity for prior 
    public comment hereon are impracticable, and that good cause exists for 
    making this amendment effective in less than 30 days.
    
    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-35-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
    
    [[Page 34165]]
    
    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, 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 
    to read as follows:
    
    AD 97-13-09  McDonnell Douglas Helicopter Systems: Amendment 39-
    10056. Docket No. 96-SW-35-AD.
    
        Applicability: Model MD-900 helicopters, 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 (d) 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 establish a life limit for various parts and reduce the 
    current life limit on other parts, accomplish the following:
        (a) Within 100 hours time-in-service (TIS) after the effective 
    date of this AD:
        (1) For Model MD-900 helicopters with serial number (S/N) 0002 
    through 0012, apply serial numbers to the mid-forward truss 
    assembly, P/N 900F2401200-102, and the forward and aft deck-fitting 
    assemblies, P/N 900F2401500-103 and P/N 900F2401600-103.
        (2) For Model MD-900 helicopters with S/N 0002 through 0048, 
    apply S/N's to the left and right vertical stabilizer control system 
    (VSCS) bellcrank assemblies, P/N 900F2341712-101 or P/N 900FP341712-
    103, and the mid-aft truss strut assembly, P/N 900F2401300-103.
        (3) Apply the S/N's as specified in paragraphs (a)(1) and (a)(2) 
    of this AD adjacent to the existing P/N's, and in accordance with 
    the Accomplishment Instructions of McDonnell Douglas Helicopter 
    Systems Service Bulletin No. SB900-039, Revision 2, dated March 12, 
    1997.
        (b) Before further flight, remove from service:
        (1) The non-rotating swashplate assembly, P/N 900C2010192-105, -
    107, -109, or -111, on or before attaining 554 hours TIS.
        (2) The collective drive link assembly, P/N 900C2010207-101, on 
    or before attaining 1,480 hours TIS.
        (3) The self-aligning, spherical/slider main rotor bearing, P/N 
    900C3010042-103, on or before attaining 480 hours TIS.
        (4) The VSCS bellcrank assembly, P/N 900FP341712-103, and 
    bellcrank arm, P/N 900F2341713-101 (used in the VSCS bellcrank 
    assembly, P/N 900F2341712-101), on or before attaining 2,700 hours 
    TIS.
        (c) This AD revises the Airworthiness Limitations section of the 
    maintenance manual by establishing new retirement lives for these 
    parts.
        (d) 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, Los Angeles Aircraft Certification 
    Office. Operators shall submit their requests through an FAA 
    Principal Maintenance Inspector, who may concur or comment and then 
    send it to the Manager, Los Angeles Aircraft Certification Office.
    
        Note 2: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the Los Angeles Aircraft Certification Office.
    
        (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 helicopter to a location where 
    the requirements of this AD can be accomplished.
        (f) The modification shall be done in accordance with McDonnell 
    Douglas Helicopter Systems Bulletin No. SB900-039, Revision 2, dated 
    March 12, 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 McDonnell Douglas 
    Helicopter Systems, Technical Publications, Bldg. 530/B11, 5000 E. 
    McDowell Road, Mesa, Arizona 85205-9797. Copies may be inspected at 
    the FAA, Office of the Assistant Chief Counsel, 2601 Meacham Blvd., 
    Room 663, Fort Worth, Texas; or at the Office of the Federal 
    Register, 800 North Capitol Street, NW., Suite 700, Washington, DC.
        (g) This amendment becomes effective on July 10, 1997.
    
        Issued in Fort Worth, Texas, on June 17, 1997.
    Eric Bries,
    Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
    [FR Doc. 97-16568 Filed 6-24-97; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
7/10/1997
Published:
06/25/1997
Department:
Federal Aviation Administration
Entry Type:
Rule
Action:
Final rule; request for comments.
Document Number:
97-16568
Dates:
Effective July 10, 1997.
Pages:
34163-34165 (3 pages)
Docket Numbers:
Docket No. 96-SW-35-AD, Amendment 39-10056, AD 97-13-09
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
97-16568.pdf
CFR: (1)
14 CFR 39.13