99-21330. Airworthiness Directives; Allison Engine Company, Inc AE 2100A and AE 2100C Series Turboprop Engines  

  • [Federal Register Volume 64, Number 161 (Friday, August 20, 1999)]
    [Rules and Regulations]
    [Pages 45421-45423]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 99-21330]
    
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 99-NE-14-AD; Amendment 39-11257; AD 99-17-09]
    RIN 2120-AA64
    
    
    Airworthiness Directives; Allison Engine Company, Inc AE 2100A 
    and AE 2100C Series Turboprop Engines
    
    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 Allison Engine Company, Inc AE 2100A and AE 2100C 
    series turboprop engines. This action requires initial and repetitive 
    visual inspections of the propeller gearbox (PGB) and power section (P/
    S) strut fittings for notches and cracks, and, if necessary, 
    replacement with serviceable parts. In addition, this action requires 
    removing and replacing strut fittings as well as reworking them to the 
    latest configuration identified by a new part number (P/N). This 
    amendment is prompted by reports of P/S strut fitting notches and 
    cracks. The actions specified in this AD are intended to prevent PGB 
    and P/S strut fitting cracks, which could result in PGB misalignment, 
    in-flight engine shutdown, and possible loss of the propeller.
    
    DATES: Effective September 7, 1999.
        The incorporation by reference of certain publications listed in 
    the regulations is approved by the Director of the Federal Register as 
    of September 7, 1999.
        Comments for inclusion in the Rules Docket must be received on or 
    before October 19, 1999.
    
    ADDRESSES: Submit comments in triplicate to the Federal Aviation 
    Administration (FAA), New England Region, Office of the Regional 
    Counsel, Attention: Rules Docket No. 99-NE-14AD, 12 New England 
    Executive Park, Burlington, MA 01803-5299. Comments may also be sent 
    via the Internet using the following address: ``adcomment@faa.gov''. Comments sent via the Internet must contain the 
    docket number in the subject line.
        The service information referenced in this AD may be obtained from 
    Rolls-Royce Allison, P.O. Box 420, Speed Code R-01B, Indianapolis, IN 
    46202-0420; telephone (317) 230-2720, fax (317) 230-3381. This 
    information may be examined at the FAA, New England Region, Office of 
    the Regional Counsel, 12 New England Executive Park, Burlington, MA; or 
    at the Office of the Federal Register, 800 North Capitol Street, NW., 
    suite 700, Washington, DC.
    
    FOR FURTHER INFORMATION CONTACT: Chung-Der Young, Aerospace Engineer, 
    Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 
    2300 East Devon Avenue, Des Plaines, IL 60018; telephone (847) 294-
    7309, fax (847) 294-7834.
    
    SUPPLEMENTARY INFORMATION: The Federal Aviation Administration (FAA) 
    has received reports of propeller gearbox (PGB) and power section (P/S) 
    strut fitting failures on Allison Engine Company AE 2100A and AE 2100C 
    series turboprop engine. The investigation revealed small radius 
    notched strut fittings on 90% of the engines inspected. Four of the P/S 
    strut fittings were cracked, and one of the PGB strut fittings was 
    cracked. The notched fittings cause a concentrated stress region that 
    can lead to cracks in the notched strut fitting areas. This condition, 
    if not corrected, could result in PGB and P/S strut fitting cracks, 
    which could result in propeller gearbox misalignment, inflight engine 
    shutdown, and possible loss of the propeller.
        The FAA has reviewed and approved the technical contents of Rolls-
    Royce Alert Service Bulletin (ASB) AE 2100A-A-72-193, also designated 
    AE 2100C-A-72-143, Revision 1, dated October 20, 1998, that describes 
    procedures for visual inspections of PGB and P/S strut fittings for 
    notches and cracks; and ASB AE 2100A-A-72-197, also designated AE 
    2100C-A-72-149, dated May 19, 1999, describes the procedures to remove 
    and replace strut fittings as well as rework them to the latest 
    configuration identified by a new part number (P/N). Rolls-Royce has 
    acquired the Allison Engine Company and now publishes the service 
    documents (including manuals and bulletins) for Allison engines.
        Since an unsafe condition has been identified that is likely to 
    exist or develop on other engines of the same type design, this AD is 
    being issued to prevent PGB and P/S strut fitting failures. This AD 
    requires visual inspections of PGB and P/S strut fittings for notches 
    and cracks. If the affected parts are found cracked, this AD requires, 
    prior to further flight, replacement with serviceable parts. If notched 
    fittings are found on both struts, this AD requires repetitive 
    inspections at intervals not to exceed 100 hours time-in-service (TIS). 
    If notched fittings are found on only one strut, the repetitive 
    inspection intervals is 400 hours TIS. In addition, this AD requires 
    removing and replacing strut fittings as well as reworking them to the 
    latest configuration identified by a new P/N. The actions are required 
    to be accomplished in accordance with the ASBs described previously.
        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 commenters' 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.
    
    [[Page 45422]]
    
        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 Number 99-NE-14-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 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, 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 the following new 
    airworthiness directive:
    
    99-17-09  Allison Engine Company, Inc: Amendment 39-11257. Docket 
    99-NE-14-AD.
    
        Applicability: Allison Engine Company, Inc. AE 2100A and AE 
    2100C series turboprop engines, installed on but not limited to SAAB 
    2000 series and Industri Pesawat Terbang Nusantara (IPTN) N-250 
    series aircraft.
    
        Note 1: This airworthiness directive (AD) applies to each engine 
    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 engines 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 (c) 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, unless accomplished 
    previously.
        To prevent propeller gearbox (PGB) and power section (P/S) strut 
    fitting cracks, which could result in PGB misalignment, in-flight 
    engine shutdown, and possible loss of the propeller, accomplish the 
    following:
        (a) Perform initial and repetitive visual inspections of the PGB 
    and P/S strut fittings for notches and cracks, and, if necessary, 
    replace with serviceable parts, in accordance with Rolls-Royce Alert 
    Service Bulletin (ASB) AE 2100A-A-72-193, also designated AE 2100C-
    A-72-143, Revision 1, dated October 20, 1998, as follows:
        (1) Perform the initial inspection within 100 hours time-in-
    service (TIS) after the effective date of this AD. Record findings 
    in Table 1 at the end of the ASB to determine the inspection 
    interval.
        (2) If parts are found cracked, prior to further flight, remove 
    from service cracked propeller gearboxes or power section strut 
    fittings and replace with serviceable parts.
        (3) If both strut fittings are found notched, thereafter inspect 
    at intervals not to exceed 100 hours timein-service (TIS) since last 
    inspection.
        (4) If one strut fitting is found notched, thereafter inspect at 
    intervals not to exceed 400 hours TIS since last inspection.
        (5) If no parts are found cracked and neither strut fitting is 
    found notched, no repetitive inspections are required, and rework 
    the strut fittings in accordance with paragraph(b) of this AD.
        (b) Perform one of the following in accordance with Rolls-Royce 
    ASB AE 2100A-A-72-197, also designated AE 2100CA-72-149, dated May 
    19, 1999:
        (1) Remove the old PGB and P/S strut fittings and install the 
    new serviceable strut fittings in accordance with the strut fittings 
    part number charts in paragraph (4) of the ASB.
        (2) Rework the existing parts within the schedule determined by 
    the inspection results of paragraph (a) of this AD in accordance 
    with the Rolls-Royce ASB AE 2100A-A-72-193, or AE 2100C-A-72-143, 
    Revision 1, dated October 20, 1998, page 12, Table 1, entries in the 
    ``Answer'' column, as follows:
        (i) If two ``Yes'' entries are contained in the ``Answer 
    Column'', rework within the next 100 hour TIS after the inspection 
    performed in accordance with paragraph (a) of this AD.
        (ii) If one ``Yes'' entry is contained in the ``Answer Column'', 
    or there are no ``Yes'' entries in the ``Answer Column'' refer to 
    Section 2 in Rolls-Royce ASB AE 2100A-A-72197, also designated AE 
    2100C-A-72-149, dated May 19, 1999, for the affected PGB and P/S 
    strut fittings rework or replace instructions.
        (iii) Following completion of the rework, mark affected parts in 
    accordance with the following configuration chart:
    
    ----------------------------------------------------------------------------------------------------------------
                     New P/N                               Name                       Old P/N              QTY/ENG
    ----------------------------------------------------------------------------------------------------------------
    23071762.................................  Fitting, Strut (RH),         23055218...................            1
                                                Propeller Gearbox.
    23071763.................................  Fitting, Strut (LH),         23055217...................            1
                                                Propeller Gearbox.
    23071764.................................  Fitting, Strut (RH), Power   23055228, 23057098.........            1
                                                Section.
    23071765.................................  Fitting, Strut (LH), Power   23055229, 23057099.........            1
                                                Section.
    ----------------------------------------------------------------------------------------------------------------
    
        (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, Chicago Aircraft Certification 
    Office. Operators shall submit their requests through an appropriate 
    FAA Principal Maintenance Inspector, who may add comments and then 
    send it to the Manager, Chicago Aircraft Certification Office.
    
        Note 2: Information concerning the existence of approved 
    alternative methods of compliance with this airworthiness directive, 
    if any, may be obtained from the Chicago Aircraft Certification 
    Office.
    
        (d) Special flight permits may be issued in accordance with 
    Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 
    21.197 and 21.199) to operate the aircraft to a
    
    [[Page 45423]]
    
    location where the inspection requirements of this AD can be 
    accomplished.
        (e) The actions required by this AD shall be done in accordance 
    with the following Rolls-Royce ASBs:
    
    ----------------------------------------------------------------------------------------------------------------
                Document No.              Pages               Revision                            Date
    ----------------------------------------------------------------------------------------------------------------
    AE 2100A-A-72-193/AE 2100C-A-72-143     1-12  1...............................  October 20, 1998.
        Total pages: 12.
    ASB AE 2100A-A-72-197/AE 2100C-A-72-    1-25  Original........................  May 19, 1999.
     149.
        Total pages: 25
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        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 Rolls-Royce Allison, P.O. Box 
    420, Speed Code R-01B, Indianapolis, IN 46202-0420; telephone (317) 
    230-2720, fax (317) 230-3381. Copies may be inspected at the FAA, 
    New England Region, Office of the Regional Counsel, 12 New England 
    Executive Park, Burlington, MA; or at the Office of the Federal 
    Register, 800 North Capitol Street, NW, suite 700, Washington, DC.
        (f) This amendment becomes effective on September 7, 1999.
    
        Issued in Burlington, Massachusetts, on August 11, 1999.
    David A. Downey,
    Assistant Manager, Engine and Propeller Directorate, Aircraft 
    Certification Service.
    [FR Doc. 99-21330 Filed 8-19-99; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
9/7/1999
Published:
08/20/1999
Department:
Federal Aviation Administration
Entry Type:
Rule
Action:
Final rule; request for comments.
Document Number:
99-21330
Dates:
Effective September 7, 1999.
Pages:
45421-45423 (3 pages)
Docket Numbers:
Docket No. 99-NE-14-AD, Amendment 39-11257, AD 99-17-09
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
99-21330.pdf
CFR: (1)
14 CFR 39.13