99-12689. Airworthiness Directives; Fokker Model F.28 Mark 0070 and 0100 Series Airplanes  

  • [Federal Register Volume 64, Number 97 (Thursday, May 20, 1999)]
    [Proposed Rules]
    [Pages 27480-27483]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 99-12689]
    
    
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    DEPARTMENT OF TRANSPORTATION
    
    Federal Aviation Administration
    
    14 CFR Part 39
    
    [Docket No. 98-NM-329-AD]
    RIN 2120-AA64
    
    
    Airworthiness Directives; Fokker Model F.28 Mark 0070 and 0100 
    Series Airplanes
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Notice of proposed rulemaking (NPRM).
    
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    SUMMARY: This document proposes the supersedure of an existing 
    airworthiness directive (AD), applicable to all Fokker Model F.28 Mark 
    0070 and 0100 series airplanes, that currently requires Airplane Flight 
    Manual (AFM) and maintenance program revisions, modifications, and 
    repetitive checks associated with ensuring the integrity of the thrust 
    reverser system. That AD was prompted by results of a review, which 
    indicated that a potential latent failure of the secondary lock 
    actuator switch 1 of the thrust reverser system in the open position 
    may occur, in addition to the potential failure of the secondary lock 
    relay 1 in the energized position. This proposed AD would continue to 
    require the modifications and repetitive checks, and would add an AFM 
    revision, repetitive operational tests, and other modifications related 
    to the thrust reverser system. The new modifications would terminate 
    the repetitive operational checks and tests. The actions specified by 
    the proposed AD are intended to ensure protection against inadvertent 
    deployment of the thrust reversers during flight, which could result in 
    reduced controllability of the airplane.
    
    DATES: Comments must be received by June 21, 1999.
    
    ADDRESSES: Submit comments in triplicate to the Federal Aviation 
    Administration (FAA), Transport Airplane Directorate, ANM-114, 
    Attention: Rules Docket No. 98-NM-329-AD, 1601 Lind Avenue, SW., 
    Renton, Washington 98055-4056. Comments may be inspected at this 
    location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
    Federal holidays.
        The service information referenced in the proposed rule may be 
    obtained from Fokker Services B.V., Technical Support Department, P.O. 
    Box 75047, 1117 ZN Schiphol Airport, the Netherlands. This information 
    may be examined at the FAA, Transport Airplane Directorate, 1601 Lind 
    Avenue, SW., Renton, Washington.
    
    FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
    International Branch, ANM-116, FAA, Transport Airplane Directorate, 
    1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
    227-2110; fax (425) 227-1149.
    
    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 shall 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 summarizing 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 Number 98-NM-329-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, Transport Airplane Directorate, ANM-114, Attention: Rules 
    Docket No. 98-NM-329-AD, 1601 Lind Avenue, SW., Renton, Washington 
    98055-4056.
    
    Discussion
    
        On December 20, 1996, the FAA issued AD 96-26-03, amendment 39-9866 
    (62 FR 604, January 6, 1997), applicable to all Fokker Model F.28 Mark 
    0070 and 0100 series airplanes, to require a revision to the Airplane 
    Flight Manual (AFM) to enable the flightcrew to determine if the thrust 
    reversers are properly stowed and locked prior to take-off. In 
    addition, that AD requires a revision to the maintenance program to 
    incorporate instructions to perform checks of the thrust reverser 
    system and correct thrust reverser malfunctions. That AD also requires 
    modifications that serve as terminating actions for the revisions to 
    the AFM and maintenance program, and repetitive checks of the thrust 
    reverser system. That action was prompted by results of a review, which 
    indicated that a potential latent failure of the secondary lock 
    actuator switch 1 of the thrust reverser system in the open position 
    may occur, in addition to the potential latent failure of the secondary 
    lock relay 1 in the energized position. The requirements of that AD are 
    intended to ensure protection against inadvertent deployment of the 
    thrust reversers during flight.
    
    Actions Since Issuance of Previous Rule
    
        In the preamble to AD 96-26-03, the FAA specified that the actions 
    required by that AD were considered to be interim action and that the 
    manufacturer would develop a modification to positively address the 
    unsafe condition. The FAA indicated that it may consider further 
    rulemaking action once a modification was developed, approved, and 
    available. The manufacturer now has developed such a modification, and 
    the FAA has determined that further rulemaking action is indeed 
    necessary; this proposed AD follows from that determination.
    
    [[Page 27481]]
    
    Relevant Service Information
    
        Fokker has issued Service Bulletin SBF100-78-014, Revision 1, dated 
    December 15, 1998, as revised by Change Notice 1, dated December 18, 
    1998, and Change Notices 2 and 3, both dated January 29, 1999. This 
    service bulletin describes procedures for modification of the thrust 
    reverser electrical control system and thrust reverser indication and 
    warning system. This modification involves connecting both systems to 
    the emergency direct current (DC) bus, and installing a new relay 
    panel, relays, and electrical circuits.
        Fokker also has issued Component Service Bulletins P41440-78-04 and 
    P41440-78-05, both dated August 15, 1998, which describe procedures for 
    modification of the aft engine cowlings. This modification involves 
    removing the cover of the terminal block (for certain airplanes, a new 
    cover must be installed), re-routing the electrical wiring of the 
    terminal block (on the side of the thrust reverser), and installing a 
    voltage spike protection diode assembly to the thrust reverser wiring.
        In addition, Fokker 70/100 Airplane Maintenance Manual 78-32-01, 
    dated June 1, 1998, describes procedures for repetitive operational 
    tests of the pilot valve and piston seal for leakage of the selector 
    valve of the thrust reversers.
        Accomplishment of these service documents is intended to adequately 
    address the identified unsafe condition. The Rijksluchtvaartdienst 
    (RLD), which is the airworthiness authority for the Netherlands, 
    classified these service bulletins as mandatory and issued Dutch 
    airworthiness directive BLA 1996-140/2, dated August 31, 1998, in order 
    to assure the continued airworthiness of these airplanes in the 
    Netherlands.
    
    FAA's Conclusions
    
        These airplane models are manufactured in the Netherlands and are 
    type certificated for operation in the United States under the 
    provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 
    21.29) and the applicable bilateral airworthiness agreement. Pursuant 
    to this bilateral airworthiness agreement, the RLD has kept the FAA 
    informed of the situation described above. The FAA has examined the 
    findings of the RLD, reviewed all available information, and determined 
    that AD action is necessary for products of this type design that are 
    certificated for operation in the United States.
    
    Explanation of Requirements of Proposed Rule
    
        Since an unsafe condition has been identified that is likely to 
    exist or develop on other airplanes of the same type design registered 
    in the United States, the proposed AD would supersede AD 96-26-03 to 
    continue to require accomplishment of modifications of the wiring of 
    the electrical control, and indication and warning systems of the 
    thrust reversers, and repetitive operational checks of the thrust 
    reverser system. This proposed AD would add requirements for a revision 
    to the Abnormal Procedures section of the FAA-approved AFM to provide 
    the flightcrew with operating procedures in the event that an unlocked 
    thrust reverser alert occurs. This proposed AD also would require 
    repetitive operational tests of the pilot valve and piston seal, for 
    leakage of the selector valve of the thrust reversers. In addition, 
    this proposed AD would require modification of the thrust reverser 
    electrical control system and thrust reverser indication and warning 
    system, and modification of the aft engine cowlings, which, when 
    accomplished, would terminate the repetitive operational checks and 
    tests. The actions would be required to be accomplished in accordance 
    with the service documents described previously, except as discussed 
    below.
    
    Differences Between This Proposed AD and Service Information
    
        Operators should note that the Fokker 70/100 Airplane Maintenance 
    Manual does not specify corrective actions if any discrepancy is 
    detected during any operational test of the pilot valve and piston seal 
    for leakage of the selector valve of the thrust reversers. This 
    proposal would require repair of any discrepancy to be accomplished in 
    accordance with a method approved by either the FAA or the RLD (or its 
    delegated agent). In light of the type of repair that would be required 
    to address the identified unsafe condition, and in consonance with 
    existing bilateral airworthiness agreements, the FAA has determined 
    that, for this proposed AD, a repair approved by either the FAA or the 
    RLD would be acceptable for compliance with this proposed AD.
    
    Cost Impact
    
        There are approximately 131 airplanes of U.S. registry that would 
    be affected by this proposed AD.
        The actions that are currently required by AD 96-26-03 take 
    approximately 20 work hours per airplane to accomplish, at an average 
    labor rate of $60 per work hour. Required parts cost approximately 
    $1,200 per airplane. Based on these figures, the cost impact of the 
    currently required actions on U.S. operators is estimated to be 
    $314,400, or $2,400 per airplane.
        The new AFM revision that is proposed in this AD action would take 
    approximately 1 work hour per airplane to accomplish, at an average 
    labor rate of $60 per work hour. Based on these figures, the cost 
    impact of the AFM revision proposed by this AD on U.S. operators is 
    estimated to be $7,860, or $60 per airplane.
        The new operational tests that are proposed in this AD action would 
    take approximately 1 work hour per airplane to accomplish, at an 
    average labor rate of $60 per work hour. Based on these figures, the 
    cost impact of the operational tests proposed by this AD on U.S. 
    operators is estimated to be $7,860, or $60 per airplane, per test 
    cycle.
        The new modifications that are proposed in this AD action would 
    take approximately 10 work hours per airplane to accomplish, at an 
    average labor rate of $60 per work hour. Required parts would cost 
    approximately $7,737 per airplane. Based on these figures, the cost 
    impact of the modifications proposed by this AD on U.S. operators is 
    estimated to be $1,092,147, or $8,337 per airplane.
        The cost impact figures discussed above are based on assumptions 
    that no operator has yet accomplished any of the current or proposed 
    requirements of this AD action, and that no operator would accomplish 
    those actions in the future if this AD were not adopted.
    
    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.
        For the reasons discussed above, I certify that this proposed 
    regulation (1) is not a ``significant regulatory action'' under 
    Executive Order 12866; (2) is not a ``significant rule'' under the 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
    
    [[Page 27482]]
    
    Flexibility Act. A copy of the draft regulatory 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, Safety.
    
    The Proposed Amendment
    
        Accordingly, pursuant to the authority delegated to me by the 
    Administrator, the Federal Aviation Administration proposes to amend 
    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 removing amendment 39-9866 (62 FR 
    604, January 6, 1997), and by adding a new airworthiness directive 
    (AD), to read as follows:
    
    Fokker Services B.V.: Docket 98-NM-329-AD. Supersedes AD 96-26-03, 
    Amendment 39-9866.
    
        Applicability: All Model F.28 Mark 0070 and 0100 series 
    airplanes, certificated in any category.
    
        Note 1: 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 (h)(1) 
    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 ensure protection against inadvertent deployment of the 
    thrust reversers during flight, which could result in reduced 
    controllability of the airplane, accomplish the following:
    
    Restatement of Certain Requirements of AD 96-26-03, Amendment 39-
    9866
    
        (a) Within 60 days after January 21, 1997 (the effective date of 
    AD 96-26-03, amendment 39-9866), modify the wiring of the electrical 
    control, and indication and warning systems of the thrust reversers, 
    in accordance with Fokker Service Bulletin SBF100-78-012, dated 
    November 22, 1996.
        (b) For Model F.28 Mark 0070 series airplanes: Prior to or in 
    conjunction with the accomplishment of paragraph (a) of this AD, 
    modify the wiring of the priority switching of the emergency 
    inverter power supply in accordance with Fokker Service Bulletin 
    SBF100-24-034, Revision 1, dated September 12, 1996.
        (c) Within 500 flight cycles following accomplishment of 
    paragraph (a) of this AD, perform operational checks to detect 
    failures of the secondary lock actuator, primary lock switch, 
    indication and warning system, and feedback cable mechanism of the 
    thrust reversers in accordance with Fokker Service Bulletin SBF100-
    78-013, dated November 22, 1996. If any failure is detected, prior 
    to further flight, repair the thrust reverser system in accordance 
    with Chapter 78-30-00 of the Fokker Airplane Maintenance Manual. 
    Repeat the operational checks thereafter at intervals not to exceed 
    500 flight cycles.
    
    New Requirements of This AD
    
    Airplane Flight Manual (AFM) Revision
    
        (d) Within 3 months after the effective date of this AD, revise 
    the Abnormal Procedures Section, Sub-section Engine, of the FAA-
    approved AFM to include the following information. This may be 
    accomplished by inserting a copy of this AD in the AFM.
    
    Reverser Unlocked Procedure on Ground (Except During Engine Start)
    
    Reverser system...........................  Maintenance action required
     
    
        Note: If alert occurs during engine start, recycle affected 
    reverser after engine start.
    
    In Flight
    
        Note: If thrust lever is not blocked at idle and no pronounced 
    buffet is present, normal operation of the aircraft may be 
    continued, although alert may persist. After landing, maintenance 
    action is required.
    
    
    ATS.......................................  (Check) Disconnect
    Affected thrust lever.....................  (Check) Idle
    Speed.....................................  Max 200 kts
    Affected fuel lever.......................  Shut
    Single engine procedure...................  Apply
     
    
        Note: Descent below 1,000 feet AGL requires that the landing be 
    completed.
    
    Repetitive Tests
    
        (e) Perform an operational test of the pilot valve and piston 
    seal for leakage of the selector valve of the thrust reversers, in 
    accordance with Fokker 70/100 Airplane Maintenance Manual 78-32-01, 
    dated June 1, 1998, at the latest of the times specified in 
    paragraphs (e)(1), (e)(2), and (e)(3) of this AD. If any discrepancy 
    is detected, prior to further flight, repair in accordance with a 
    method approved by either the Manager, International Branch, ANM-
    116, FAA, Transport Airplane Directorate; or the RLD (or its 
    delegated agent). Repeat the operational test thereafter at 
    intervals not to exceed 12,000 flight hours.
        (1) For airplanes on which Fokker Service Bulletin SBF100-78-
    004, Revision 1, dated November 22, 1996, has been accomplished 
    prior to the effective date of this AD: Within 12,000 flight hours 
    after accomplishment of Fokker Service Bulletin SBF100-78-004, 
    Revision 1, dated November 22, 1996.
        (2) Within 6,000 flight hours after accomplishment of Fokker 
    Service Bulletin SBF100-78-012, dated November 22, 1996.
        (3) Within 500 flight hours after the effective date of this AD.
    
    Terminating Modifications
    
        (f) Within 18 months after the effective date of this AD, 
    concurrently accomplish the requirements of paragraphs (f)(1) and 
    (f)(2) of this AD. Accomplishment of these modifications constitutes 
    terminating action for the repetitive operational checks and 
    operational tests required by paragraphs (c) and (e) of this AD.
        (1) Modify the thrust reverser electrical control system and 
    thrust reverser indication and warning system, in accordance with 
    Fokker Service Bulletin SBF100-78-014, Revision 1, dated December 
    15, 1998; as revised by Change Notice 1, dated December 18, 1998, 
    and Change Notices 2 and 3, both dated January 29, 1999.
        (2) Modify the aft engine cowlings in accordance with Fokker 
    Component Service Bulletins P41440-78-04 and P41440-78-05, both 
    dated August 15, 1998.
    
    Spares
    
        (g) As of the effective date of this AD, no person shall install 
    on any airplane an aft engine cowling having part number 1159P41440, 
    unless it has been modified in accordance with paragraph (f)(2) of 
    this AD.
    
    Alternative Methods of Compliance
    
        (h)(1) 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, International Branch, ANM-116, FAA, 
    Transport Airplane Directorate. Operators shall submit their 
    requests through an appropriate FAA Principal Maintenance Inspector, 
    who may add comments and then send it to the Manager, International 
    Branch, ANM-116.
        (h)(2) Alternative methods of compliance, approved previously in 
    accordance with AD 96-26-03, amendment 39-9866 for accomplishment of 
    paragraph (c) of that AD, are approved as alternative methods of 
    compliance with paragraph (a) of this AD.
    
        Note 2: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the International Branch, ANM-116.
    
    Special Flight Permits
    
        (i) 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.
    
        Note 3: The subject of this AD is addressed in Dutch 
    airworthiness directive BLA 1996-140/2, dated August 31, 1998.
    
    
    [[Page 27483]]
    
    
        Issued in Renton, Washington, on May 13, 1999.
    D.L. Riggin,
    Acting Manager, Transport Airplane Directorate, Aircraft Certification 
    Service.
    [FR Doc. 99-12689 Filed 5-19-99; 8:45 am]
    BILLING CODE 4910-13-P
    
    
    

Document Information

Published:
05/20/1999
Department:
Federal Aviation Administration
Entry Type:
Proposed Rule
Action:
Notice of proposed rulemaking (NPRM).
Document Number:
99-12689
Dates:
Comments must be received by June 21, 1999.
Pages:
27480-27483 (4 pages)
Docket Numbers:
Docket No. 98-NM-329-AD
RINs:
2120-AA64: Airworthiness Directives
RIN Links:
https://www.federalregister.gov/regulations/2120-AA64/airworthiness-directives
PDF File:
99-12689.pdf
CFR: (1)
14 CFR 39.13