94-15596. Airworthiness Directives; Boeing Model 757 Series Airplanes Equipped With Rolls Royce RB211-535C Engines  

  • [Federal Register Volume 59, Number 125 (Thursday, June 30, 1994)]
    [Unknown Section]
    [Page 0]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 94-15596]
    
    
    [[Page Unknown]]
    
    [Federal Register: June 30, 1994]
    
    
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    DEPARTMENT OF TRANSPORTATION
    14 CFR Part 39
    
    [Docket No. 93-NM-143-AD; Amendment 39-8954; AD 94-14-02]
    
     
    
    Airworthiness Directives; Boeing Model 757 Series Airplanes 
    Equipped With Rolls Royce RB211-535C Engines
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule.
    
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    SUMMARY: This amendment adopts a new airworthiness directive (AD), 
    applicable to certain Boeing Model 757 series airplanes, that requires 
    tests of the thrust reverser system, and repair, if necessary; 
    installation of a modification that would terminate those tests; and 
    repetitive operational checks of that installation, and repair, if 
    necessary. This amendment is prompted by results of a safety review, 
    which revealed that in-flight deployment of a thrust reverser could 
    result in a significant reduction in the controllability of the 
    airplane. The actions specified by this AD are intended to prevent 
    deployment of a thrust reverser in flight and subsequent reduced 
    controllability of the airplane.
    
    DATES: Effective August 1, 1994.
        The incorporation by reference of certain publications listed in 
    the regulations is approved by the Director of the Federal Register as 
    of August 1, 1994.
    
    ADDRESSES: The service information referenced in this AD may be 
    obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, 
    Washington 98124-2207; and Rolls-Royce plc, P.O. Box 31, Derby DE24 
    8BJ, England, ATTN: Technical Publications Department. This information 
    may be examined at the Federal Aviation Administration (FAA), Transport 
    Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, 
    Washington; or at the Office of the Federal Register, 800 North Capitol 
    Street, NW., suite 700, Washington, DC.
    
    FOR FURTHER INFORMATION CONTACT: Jeffrey Duven, Aerospace Engineer, 
    Propulsion Branch, ANM-140S, FAA, Transport Airplane Directorate, 
    Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, 
    Washington 98055-4056; telephone (206) 227-2688; fax (206) 227-1181.
    
    SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
    Aviation Regulations (14 CFR part 39) to include an airworthiness 
    directive (AD) that is applicable to certain Boeing Model 757 series 
    airplanes was published in the Federal Register on October 4, 1993 (58 
    FR 51589). That action proposed to require tests of the thrust reverser 
    system, and repair, if necessary; installation of a modification that 
    would terminate those tests; and repetitive operational checks of that 
    installation, and repair, if necessary. -
        Interested persons have been afforded an opportunity to participate 
    in the making of this amendment. Due consideration has been given to 
    the comments received.
        One commenter supports the proposed rule. -
        Boeing requests that specific references to page numbers and 
    revision dates of the Boeing 757 Airplane Maintenance Manual (AMM) be 
    eliminated from the proposed rule, and that the proposal be amended to 
    include copies of the required test procedures so that reference to the 
    AMM would not be necessary. -
        Boeing explains that the AMM's are customized for each operator to 
    reflect all of the equipment in that operator's fleet. Therefore, the 
    number of pages for any given procedure is variable, depending on the 
    number of different equipment configurations documented in an 
    operator's AMM. Boeing also indicates that AMM procedures are revised 
    periodically for non-technical reasons. Boeing adds that changes to the 
    structure of the procedures are necessary to accommodate an upgrade of 
    the publishing system that is currently under way, which, in addition 
    to repagination, will necessitate the issuance of revised AMM pages. -
        Boeing states that the effect of specifying AMM page numbers and 
    revision dates in the AD is that operators may be unable to use the 
    procedure contained in the AMM to perform certain tests required by the 
    AD. Each operator would be required to maintain an obsolete version of 
    the procedure, or to request FAA approval of an alternative method of 
    compliance with the AD that would allow the use of the current version 
    of the AMM.
        The FAA concurs partially. In light of the information submitted by 
    the commenter, the FAA finds that specific AMM page numbers and dates 
    should not be specified in the final rule. Therefore, such references 
    have been removed from paragraphs (a)(1) and (a)(2) of the final rule. 
    However, for those paragraphs, the FAA does not agree that copies of 
    the specific procedures should be included in the final rule. 
    Therefore, paragraphs (a)(1) and (a)(2) of the final rule have been 
    revised to cite only the appropriate section and task title specified 
    in the AMM for accomplishment of the tests required by those 
    paragraphs.
        The FAA's objective in proposing periodic operational checks of the 
    sync-lock device, as specified in paragraph (c) of this AD, is to 
    ensure the integrity of the locking function. However, subsequent to 
    the issuance of the proposal and the receipt of Boeing's comments to 
    the proposal, Boeing has submitted to the FAA separate procedures for 
    accomplishment of the operational check of the sync-lock integrity. 
    These procedures have been defined in paragraph (c) of the final rule; 
    therefore, the AMM references specified in paragraph (c) of the NPRM 
    have been removed from the final rule. Additionally, the procedures for 
    the operational checks are accomplished independently of the other 
    thrust reverser system tests specified in the proposal. Accordingly, 
    the FAA has revised paragraph (c) of the final rule to require periodic 
    accomplishment of operational checks of the sync-lock integrity only, 
    and has removed the requirement for accomplishment of other tests 
    specified in that paragraph of the proposal. -
        The Air Transport Association (ATA) of America, on behalf of its 
    members, states that, while ATA members are not opposed to 
    accomplishing the operational checks specified in paragraph (c) of the 
    proposal as part of their maintenance programs, these members are 
    opposed to accomplishing the checks as part of the requirements of an 
    AD. The commenters believe that the adoption of paragraph (c), as 
    proposed, is equivalent to issuing a Certification Maintenance 
    Requirements (CMR) item by means of an AD. -
        ATA adds that, if the FAA finds sufficient justification to include 
    the requirement for operational checks in the AD, an alternative to 
    accomplishment of the checks should be provided in the final rule. ATA 
    reasons that an alternative is justified because no data exist to show 
    that repetitive checks of a modified thrust reverser cannot be handled 
    adequately through an operator's maintenance program. The suggested 
    alternative follows: Within 3 months after accomplishing the sync-lock 
    installation, revise the FAA- approved maintenance inspection program 
    to include an operational check of the sync-lock. The initial check 
    would be accomplished within 1,000 hours time-in-service after 
    modification. The AD would no longer be applicable for operators that 
    have acceptably revised the maintenance program. Operators choosing 
    this alternative could use an alternative recordkeeping method in lieu 
    of that required by Federal Aviation Regulation (FAR) 91.417 or 121.380 
    (14 CFR 91.417 or 121.380). The FAA would be defined as the cognizant 
    Principal Maintenance Inspector (PMI) for operators electing this 
    alternative.
        One commenter, Boeing, requests that the proposed requirement for 
    operational checks be removed from the AD until the FAA reviews the 
    ``more comprehensive'' scheduled maintenance recommendations developed 
    by the Model 757/767 Thrust Reverser Working Group, which will be 
    recommended in the next revision to the Maintenance Review Board (MRB) 
    report. Boeing believes that adoption of the maintenance 
    recommendations contained in that forthcoming revision will ensure that 
    an adequate level of safety (with regard to the sync-lock installation) 
    will be maintained by all operators of Model 757 series airplanes.
        The FAA recognizes the concerns of these commenters regarding the 
    requirement for periodic operational checks of the sync-lock following 
    its installation. However, the FAA finds that the operational checks 
    are necessary in order to provide an adequate level of safety and to 
    ensure the integrity of the sync-lock installation. The actions 
    required by this AD are consistent with actions that have been 
    identified by an industry-wide task force as necessary to ensure 
    adequate safety of certain thrust reverser systems installed on 
    transport category airplanes. Representatives of the Aerospace 
    Industries Association (AIA) of America, Inc., and the FAA comprise 
    that task force. Representatives from other organizations, such as ATA, 
    have participated in various discussions and work activities resulting 
    from the recommendations of the task force.
        The FAA acknowledges that the operational checks specified in this 
    AD and CMR items are similar in terms of scheduled maintenance and 
    recordkeeping. This AD addresses an unsafe condition and requires 
    installation of the sync-lock to correct that unsafe condition. The FAA 
    has determined that the requirement for operational checks is necessary 
    in order to ensure the effectiveness of that installation in addressing 
    the unsafe condition. This determination is based on the fact that the 
    sync-lock is a new design whose reliability has not been adequately 
    proven through service experience. In addition, service experience to 
    date has demonstrated that failures can occur within the sync-lock that 
    may not be evident during normal operation of the thrust reverser 
    system and may not result in activation of the sync-lock ``unlock'' 
    indicator. The ATA's suggested alternative to accomplishment of the 
    operational checks would permit each operator to determine whether and 
    how often these checks should be conducted. In light of the severity of 
    the unsafe condition, however, the FAA has determined that allowing 
    this degree of operator discretion is not appropriate at this time. 
    Therefore, this AD is necessary to ensure that operators accomplish 
    checks of the integrity of the sync-lock installation in a common 
    manner and at common intervals.
        The FAA also finds that addressing operational checks of the sync-
    lock integrity in a recommended action, such as an MRB report, will not 
    ensure an acceptable level of safety with regard to the thrust reverser 
    system. However, the FAA recognizes that an operational check interval 
    of 4,000 hours time-in-service, which will be recommended by Boeing for 
    inclusion in the next revision to the MRB report, corresponds more 
    closely to the interval at which most of the affected operators conduct 
    regularly scheduled ``C'' checks. The FAA has reconsidered the proposed 
    interval of 1,000 hours time-in-service for accomplishment of 
    repetitive operational checks. In light of the safety implications of 
    the unsafe condition addressed and the practical aspects of 
    accomplishing orderly operational checks of the fleet during regularly 
    scheduled maintenance where special equipment and trained maintenance 
    personnel will be readily available, the FAA finds that accomplishment 
    of the checks at intervals of 4,000 hours time-in-service will provide 
    an acceptable level of safety. Paragraph (c) of the final rule has been 
    revised accordingly.
        Since the issuance of the proposed rule, Boeing has issued Revision 
    2 of Service Bulletin 757-78-0035, dated June 23, 1994. The service 
    bulletin revision moves general work instruction Step B from Work 
    Package 2 to Step Q in Work Package 8. In Revision 1 of the service 
    bulletin, Step B of Work Package 2 specified procedures for removal of 
    the ground to the EICAS for the REV ISLN VAL message; however, the 
    ground should not be removed as part of Work Package 2. Rather, the 
    ground should be removed as part of Work Package 8 in order to avoid 
    loss of the REV ISLN VAL message on EICAS. Revision 2 of the service 
    bulletin correctly describes procedures for removal of the ground as 
    part of Work Package 8. Revision 2 of the service bulletin also 
    describes procedures for installation of an additional bracket on the 
    P36 disconnect bracket and to make a cutout on the P37 disconnect 
    bracket on certain airplanes.
        The FAA has reviewed and approved this latest revision to the 
    service bulletin and has revised the final rule to reflect it as the 
    appropriate source of service information. The FAA finds that citing 
    this latest revision to the service bulletin will impose no additional 
    burden on any operator.
        It should be noted that Revision 2 of Boeing Service Bulletin 757-
    78-0035 references Rolls-Royce Service Bulletins RB.211-78-9725 and 
    RB.211-78-9726 as additional sources of service information for 
    accomplishment of the originally proposed sync-lock installation. 
    However, the Boeing service bulletin does not specify the appropriate 
    revision levels for the Rolls-Royce service bulletins. Therefore, the 
    FAA has added ``NOTE 1'' to paragraph (b) of this AD to specify that 
    the intent of that paragraph is that the appropriate revision levels 
    for the Rolls-Royce service bulletins that are to be used in 
    conjunction with Boeing Service Bulletin 757-78-0035 are as follows: 
    Rolls-Royce Service Bulletin RB.211-78-9725, dated June 23, 1993, or 
    Revision 1, dated January 7, 1994; and Rolls-Royce Service Bulletin 
    RB.211-78-9726, dated June 23, 1993, or Revision 1, dated October 1, 
    1993.
        In addition, since the issuance of the proposed rule, Rolls-Royce 
    has issued Service Bulletin RB.211-78-9822, dated October 1, 1993. This 
    service bulletin describes procedures for installation of a revised 
    thrust reverser sync-lock. The FAA has determined that accomplishment 
    of the actions described in this service bulletin, in conjunction with 
    Boeing Service Bulletin 757-78-0035 [which was cited in paragraph (b) 
    of the proposal as the appropriate source of service information for 
    installation of an additional thrust reverser system locking feature], 
    constitutes an acceptable alternative to the sync-lock installation 
    specified in paragraph (b) of the proposal.
        In light of this information, paragraph (b) of the final rule has 
    been revised to include paragraph (b)(1), which contains the 
    requirement for installation of an additional thrust reverser system 
    locking feature that was specified in the proposed rule, and paragraph 
    (b)(2), which provides for installation of a revised thrust reverser 
    sync-lock as an acceptable alternative to paragraph (b)(1) of this AD. 
    Accomplishment of the revised installation specified in paragraph 
    (b)(2) requires no additional work hours beyond the 514 work hours 
    specified in the economic impact information, below, for accomplishment 
    of the originally proposed sync-lock installation.
        Additionally, it should be noted that Rolls-Royce Service Bulletin 
    RB.211-78-9822 references Rolls-Royce Service Bulletin RB.211-78-9726 
    as an additional source of service information for airplanes equipped 
    with Rolls-Royce RB211-535C engines. Rolls-Royce Service Bulletin 
    RB.211-78-9726 references Rolls-Royce Service Bulletin RB.211-78-9725 
    as an additional source of service information. However, the 
    appropriate revision levels for these service bulletins are not 
    specified in Boeing Service Bulletin 757-78-0035 or in any of the 
    Rolls-Royce service bulletins. Therefore, the FAA has added ``NOTE 2'' 
    to paragraph (b) of the final rule to specify that the appropriate 
    revision levels for Rolls-Royce Service Bulletins RB.211-78-9726 and 
    RB.211-78-9725, used in conjunction with Rolls-Royce Service Bulletin 
    RB.211-78-9822, are as follows: Rolls-Royce Service Bulletin RB.211-78-
    9726, dated June 23, 1993, or Revision 1, dated October 1, 1993; and 
    Rolls-Royce Service Bulletin RB.211-78-9725, dated June 23, 1993, or 
    Revision 1, dated January 7, 1994.
        After careful review of the available data, including the comments 
    noted above, the FAA has determined that air safety and the public 
    interest require the adoption of the rule with the changes previously 
    described. The FAA has determined that these changes will neither 
    increase the economic burden on any operator nor increase the scope of 
    the AD.
        There are approximately 40 Model 757 series airplanes of the 
    affected design in the worldwide fleet. Currently, there are no Model 
    757 series airplanes of the affected design on the U.S. Register. 
    However, should an affected airplane be imported and placed on the U.S. 
    Register in the future, it will take approximately 1 work hour per 
    airplane to accomplish the required auto restow and integrity tests, 
    514 work hours per airplane to accomplish either modification specified 
    in paragraph (b)(1) or (b)(2) of this AD, and 1 work hour per airplane 
    to accomplish the required operational checks; at an average labor rate 
    of $55 per work hour. Required parts are currently planned to be 
    supplied by the manufacturer at no cost to operators. Based on these 
    figures, the total cost impact of the AD is estimated to be $28,380 per 
    airplane.
        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.
        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) 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 final evaluation has been prepared for this action 
    and it is contained in the Rules Docket. A copy of it 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 
    106(g); and 14 CFR 11.89.
    
    
    Sec. 39.13  [Amended]
    
        2. Section 39.13 is amended by adding the following new 
    airworthiness directive:
    
    94-14-02 Boeing: Amendment 39-8954. Docket 93-NM-143-AD.
    
        Applicability: Model 757 series airplanes equipped with Rolls 
    Royce RB211-535C engines, as listed in Boeing Service Bulletin 757-
    78-0035, Revision 2, dated June 23, 1994; certificated in any 
    category.
        Compliance: Required as indicated, unless accomplished 
    previously.
        To prevent deployment of a thrust reverser in flight and 
    subsequent reduced controllability of the airplane, accomplish the 
    following:
        (a) For airplanes on which the sync-lock feature has not been 
    installed as a modification in accordance with Boeing Service 
    Bulletin 757-78-0035: Within 4,000 hours time-in-service after the 
    effective date of this AD; and thereafter at intervals not to exceed 
    4,000 hours time-in-service until the modification required by 
    paragraph (b) of this AD is accomplished; accomplish paragraphs 
    (a)(1) and (a)(2) of this AD to verify proper operation of the 
    thrust reverser system. Prior to further flight, repair any 
    discrepancy found, in accordance with the procedures described in 
    the Boeing 757 Maintenance Manual.
        (1) Perform a ``Thrust Reverser-Auto Restow Test'' in accordance 
    with the procedures described in Section 78-31-00 of the Boeing 757 
    Maintenance Manual.
        (2) Perform an ``Actuator Lock and Crossover Shaft Integrity 
    Test'' in accordance with the procedures described in Section 78-31-
    00 of the Boeing 757 Maintenance Manual.
        (b) For airplanes on which the sync-lock feature has not been 
    installed as a modification in accordance with Boeing Service 
    Bulletin 757-78-0035: Within 5 years after the effective date of 
    this AD, accomplish the requirements of paragraph (b)(1) or (b)(2) 
    of this AD. Accomplishment of either of these installations 
    constitutes terminating action for the tests required by paragraph 
    (a) of this AD.
        (1) Install an additional thrust reverser system locking feature 
    (sync-lock installation) in accordance with Boeing Service Bulletin 
    757-78-0035, Revision 2, dated June 23, 1994.
    
        Note 1: Boeing Service Bulletin 757-78-0035 references Rolls-
    Royce Service Bulletins RB.211-78-9725 and RB.211-78-9726 as 
    additional sources of service information. The intent of paragraph 
    (b)(1) of this AD is that the appropriate revision levels for the 
    Rolls-Royce service bulletins that are to be used in conjunction 
    with Boeing Service Bulletin 757-78-0035 are as follows: Rolls-Royce 
    Service Bulletin RB.211-78-9725, dated June 23, 1993, or Revision 1, 
    dated January 7, 1994; and Rolls-Royce Service Bulletin RB.211-78-
    9726, dated June 23, 1993, or Revision 1, dated October 1, 1993.
    
        (2) Install a revised thrust reverser sync-lock in accordance 
    with Boeing Service Bulletin 757-78-0035, Revision 2, dated June 23, 
    1994, and Rolls-Royce Service Bulletin RB.211-78-9822, dated October 
    1, 1993.
    
        Note 2: Rolls-Royce Service Bulletin RB.211-78-9822 references 
    Rolls-Royce Service Bulletin RB.211-78-9726 as an additional source 
    of service information for airplanes equipped with Rolls-Royce 
    RB211-535C engines. Rolls-Royce Service Bulletin RB.211-78-9726 
    references Rolls-Royce Service Bulletin RB.211-78-9725 as an 
    additional source of service information. The FAA's intent is that 
    the appropriate revision levels of Rolls-Royce Service Bulletins 
    RB.211-78-9726 and RB.211-78-9725, used in conjunction with Rolls-
    Royce Service Bulletin RB.211-78-9822, are as follows: Rolls-Royce 
    Service Bulletin RB.211-78-9726, dated June 23, 1993, or Revision 1, 
    dated October 1, 1993; and Rolls-Royce Service Bulletin RB.211-78-
    9725, dated June 23, 1993, or Revision 1, dated January 7, 1994.
    
        (c) Within 4,000 hours time-in-service after accomplishing the 
    modification required by paragraph (b) of this AD, or within 4,000 
    hours time-in-service after the effective date of this AD, whichever 
    occurs later; and thereafter at intervals not to exceed 4,000 hours 
    time-in-service: Accomplish the thrust reverser sync-lock integrity 
    test defined below to verify that the sync-locks have not failed in 
    the ``unlocked'' state. Prior to further flight, repair any 
    discrepancy found, in accordance with procedures described in the 
    Boeing 757 Maintenance Manual.
    
    Thrust Reverser Sync-Lock Integrity Test
    
    1. General
    
        A. Use this procedure to test the integrity of the thrust 
    reverser sync locks. The procedure must be performed on each engine.
    
    2. Thrust Reverser Sync Lock Test
    
        A. Prepare for the thrust reverser sync lock test.
        (1) Open the AUTO SPEEDBRAKE circuit breaker on the overhead 
    circuit breaker panel, P11.
        (2) Do the steps that follow to supply power to the thrust 
    reverser system:
        (a) Make sure the thrust levers are in the idle position.
        (b) Make sure the thrust reversers are retracted and locked.
        (c) Make sure these circuit breakers on the main power 
    distribution panel, P6, are closed:
    
    (1) L ENG SYNC LOCK
    (2) R ENG SYNC LOCK-ALTN
    
        (d) Make sure these circuit breakers on the overhead circuit 
    breaker panel, P11, are closed:
    
    (1) LANDING GEAR POS SYS 1
    (2) T/R IND R
    (3) T/R CONT-ALTN-R
    (4) T/R IND L
    (5) T/R CONT L
    (6) R ENG SYNC LOCK
    (7) T/R CONT R
    (8) EICAS CMPTR LEFT
    (9) EICAS UPPER IND
    (10) EICAS CMPTR RIGHT
    (11) EICAS LOWER IND
    (12) EICAS DISPLAY SW
    (13) EICAS PILOTS DSP
    (14) AIR/GND SYS 1
    (15) AIR/GND SYS 2
    (16) LANDING GEAR POS SYS 2
    (17) PROX SW TEST
    
        (e) Supply electrical power.
        (f) Supply pressure to the left (for the left engine) or right 
    (for the right engine) hydraulic system.
        B. Do the thrust reverser sync lock test.
        (1) Use the SENSOR CHANNEL SELECT thumb switches to set the PSEU 
    code for the auto-restow proximity sensor.
    (a) On PSEU (-17), The left engine code is 433.
    (b) On PSEU (-16), The left engine code is 105.
    (c) The right engine PSEU code is 099.
    
        Note: The following step will cause the Hydraulic Isolation 
    Valve (HIV) to open for approximately 5 seconds. The next 3 steps 
    must be done during this 5 second time. These 4 steps may be 
    repeated if required.
    
        (2) Push the TARGET TEST switch on the PSEU and hold for one 
    second.
        (3) Make sure the TARGET NEAR light on the PSEU comes on after 
    approximately four seconds.
        (4) Make sure that the EICAS Advisory message L(R) REV ISLN VAL 
    shows for approximately 3 seconds and then does not show.
        (5) Make sure the sync lock manual unlock lever on the right 
    sleeve of the reverser does not extend.
        (6) Push and release the RESET switch on the PSEU.
        (7) Open the applicable circuit breaker(s):
        (a) For the left engine; L ENG SYNC LOCK (Panel P6)
        (b) For the right engine; R ENG SYNC LOCK (Panel P11) R ENG SYNC 
    LOCK-ALTN (Panel P6)
        (8) Move the left (right) reverse thrust lever up and rearward 
    to the reverse thrust position.
        (9) Make sure that the thrust reverser does not extend.
        (10) Move the left (right) reverse thrust lever to the forward 
    and down position.
        C. Put the airplane back to its usual condition.
        (1) Remove hydraulic pressure.
        (2) Close the applicable circuit breaker(s).
        (a) For the left engine; L ENG SYNC LOCK (Panel P6)
        (b) For the right engine; R ENG SYNC LOCK (Panel P11) R ENG SYNC 
    LOCK-ALTN (Panel P6)
        (3) Close the AUTO SPEEDBRAKE circuit breaker on the overhead 
    circuit breaker panel, P11.
        (4) Remove electrical power.
        D. Repeat the thrust reverser sync lock test on the other 
    engine.
    
        (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, Seattle Aircraft Certification 
    Office (ACO), 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, Seattle ACO.
    
        Note 3: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the Seattle ACO.
    
        (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 airplane to a location where 
    the requirements of this AD can be accomplished.
        (f) The installation shall be done in accordance with Boeing 
    Service Bulletin 757-78-0035, Revision 2, dated June 23, 1994; and 
    Rolls-Royce Service Bulletin RB.211-78-9822, dated October 1, 1993. 
    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 Boeing Commercial Airplane Group, 
    P.O. Box 3707, Seattle, Washington 98124-2207; and Rolls-Royce plc, 
    P.O. Box 31, Derby DE24 8BJ, England, ATTN: Technical Publications 
    Department. Copies may be inspected at the FAA, Transport Airplane 
    Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the 
    Office of the Federal Register, 800 North Capitol Street, NW., suite 
    700, Washington, DC.
        (g) This amendment becomes effective on August 1, 1994.
    
        Issued in Renton, Washington, on June 22, 1994.
    S.R. Miller,
    Acting Manager, Transport Airplane Directorate, Aircraft Certification 
    Service.
    [FR Doc. 94-15596 Filed 6-29-94; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
8/1/1994
Published:
06/30/1994
Department:
Transportation Department
Entry Type:
Uncategorized Document
Action:
Final rule.
Document Number:
94-15596
Dates:
Effective August 1, 1994.
Pages:
0-0 (1 pages)
Docket Numbers:
Federal Register: June 30, 1994, Docket No. 93-NM-143-AD, Amendment 39-8954, AD 94-14-02
CFR: (1)
14 CFR 39.13