Federal Register: July 13, 2004 (Volume 69, Number 133)

DOCID: FR Doc 04-15760

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

CFR Citation: 14 CFR Part 39

Docket ID: [Docket No. 2000-NM-32-AD]

RIN ID: RIN 2120-AA64

NOTICE: PROPOSED RULES

ACTION: Airworthiness directives:

DOCUMENT ACTION: Supplemental notice of proposed rulemaking; reopening of comment period.

SUBJECT CATEGORY:

Airworthiness Directives; McDonnell Douglas Model MD-11 and -11F Airplanes

DATES: Comments must be received by August 9, 2004.

DOCUMENT SUMMARY:

This document revises an earlier proposed airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD11 and 11F airplanes, that would have required resistance tests of the brake coils of the auto throttle servo (ATS) and of the elevator load feel (ELF)/flap limiter (FL) duplex actuator for low electrical resistance; and corrective actions, if necessary. This new action revises the proposed rule by removing the resistance tests, adding certain airplanes to the applicability, and adding an inspection of the ATS assembly and corrective actions if necessary. The actions specified by this new proposed AD are necessary to prevent electrical shorting of the brake coils of the ATS, which could result in smoke in the cockpit and/or passenger cabin. This action is intended to address the identified unsafe condition.

SUMMARY:

McDonnell Douglas,

SUPPLEMENTAL 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 action may be changed in light of the comments received.

Submit comments using the following format:

  • Organize comments issuebyissue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
  • For each issue, state what specific change to the proposed AD is being requested.
  • Include justification (e.g., reasons or data) for each request.

    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 FAApublic 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 action must submit a selfaddressed, stamped postcard on which the following statement is made: ``Comments to Docket Number 2000NM32AD.'' 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, ANM114, Attention: Rules Docket No. 2000NM32AD, 1601 Lind Avenue, SW., Renton, Washington 980554056.

    Discussion

    A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to certain McDonnell Douglas Model MD11 and 11F airplanes, was published as notice of proposed rulemaking (NPRM) in the Federal Register on July 27, 2000 (65 FR 46210) (hereafter referred to as the ``original NPRM''). The original NPRM would have required resistance tests of the brake coils of the auto throttle servo (ATS) and of the elevator load feel (ELF)/flap limiter (FL) duplex actuator for low electrical resistance; and corrective actions, if necessary. The original NPRM was prompted by an incident in which the ATS shorted electrically and caused smoke in the cockpit. Electrical shorting of the brake coils of the ATS or ELF/FL duplex actuator, if not corrected, could result in smoke in the cockpit and/or passenger cabin.

    Actions Since the Issuance of Original NPRM

    Since the issuance of the original NPRM, we have reviewed and approved Boeing Service Bulletin MD1122026, dated December 19, 2003. The service bulletin supersedes and cancels the
    [[Page 41986]]
    recommendations of Boeing Service Bulletins MD1122024 and MD1122025 (original and Revision 01). The service bulletin describes procedures for performing an inspection to determine the P/N of the ATS assembly of the servo assembly of the TCM, and corrective action(s) if necessary. The corrective actions include reidentifying the TCM assembly; and replacing the existing ATS assembly of the TCM assembly with a new ATS assembly or returning the TCM assembly in the center of the pedestal in the flight compartment to Boeing for modification and reidentification. Accomplishment of the actions specified in the Boeing Service Bulletin MD1122026 is intended to adequately address the identified unsafe condition. Therefore, we have revised the supplemental NPRM to reference Boeing Service Bulletin MD1122026 as the appropriate source of service information.

    Comments

    Due consideration has been given to the comments received in response to the original NPRM.

    Request To Change Dash Number of Affected Spare Parts

    Two commenters request that the FAA require Boeing and Honeywell to change the dash numbers on all parts affected by the original NPRM. To do this, one commenter suggests that the manufacturers' revise the following service information:

    1. Boeing Service Bulletin MD1122024, dated March 29, 2000 (which is referenced in the original NPRM as the appropriate source of service information for accomplishing the proposed actions);

    2. Honeywell Service Bulletins 4059004220003 and 4059005270004 (Boeing Service Bulletin MD1122024 references these Honeywell service bulletins as an additional source of service information for accomplishing the proposed resistance tests);

    3. Boeing Component Maintenance Manuals (CMM) 761005; and

    4. Honeywell CMMs 223160 and 273207.

    Several commenters note that paragraph (b) of the original NPRM states, ``As of the effective date of this AD, no person shall install the following parts on any airplane: (1) Thrust control module assembly having part number ABH77601, ABH7760501, or ABH7760503; (2) Flap limiter duplex actuator having part number 4059004901; or (3) Elevator load feel duplex actuator having part number 4059005901.'' Two of the commenters state that none of the service information listed above recommend reidentification of thrust control module (TCM) assembly having part number ABH77601, ABH7760501, or ABH7760503, but do recommend reidentification with a modication letter ``K'' after the resistance tests of ATSs having part number (P/N) 4059004901a subassembly of the TCM, and ELF/FL duplex actuators having P/N 4059005 901. Another commenter made a similar statement. One of the commenters specifically points out that P/N 4059004901 in paragraph (b)(2) of the original NPRM actually belongs to the ATS, which is the subassembly of the TCM, and that P/N 4059005901 in paragraph (b)(3) of the original NPRM applies to both the ELF and FL installations.

    One of the commenters notes that reidentification per a modification letter does not constitute a part number change, and that parts are not purchased, stocked, tracked, or identified in an airplane illustrated parts catalog using modification letters. Therefore, the commenter concludes that a modification letter change will do very little to help prevent premodification parts from being installed on an airplane.

    In addition, one commenter requests that provisions be added to Boeing Service Bulletin MD1122024 to allow operators to perform the resistance check on all affected spares without special routings to shop for complete disassembly and date code checks. The commenter states that spares should be reidentified with the new dash number and returned to stock provided they pass all resistance checks.

    The FAA does not agree with the commenters' request to require Boeing and Honeywell to update the respective CMMs. Because CMMs are not FAAapproved and the procedures specified in CMMs vary from operator to operator, there are no assurances that each operator's CMM contains the identical actions proposed by this supplemental NPRM. These changes should be negotiated between the affected operators and Boeing.

    However, we agree with the commenter's statement that the Boeing and Honeywell service bulletins listed above need to be revised, but for different reasons. Since the issuance of the original NPRM, we have determined that the ELF/FL duplex actuators are not subject to the identified unsafe condition of this AD. These actuators are installed outside of the cockpit and passenger cabin such that the possibility of smoke in the cockpit or cabin is minimized. Also, we have determined that all ATSs that have not been upgraded to P/N 4059005903 are subject to electrical shorting, and that the proposed resistance tests in the original NPRM are not adequate to detect all defective ATSs. Therefore, all ATSs must be inspected to determine if they have been upgraded to P/N 4059005903 per Boeing Service Bulletin MD1122026 (described previously).

    Explanation of Change to Applicability

    We have determined that some confusion may arise from the applicability of the original NPRM, because McDonnell Douglas Model MD 11F series airplanes were not specifically identified. However, those airplanes were identified by manufacturer's fuselage numbers in Boeing Service Bulletin MD1122024, dated March 29, 2000 (which was referenced in the applicability statement of the original NPRM for determining the specific affected airplanes). Therefore, we have revised the applicability of the supplemental NPRM to include Model MD 11F airplanes, in addition to Model MD11 series airplanes, and to reference Boeing Service Bulletin MD1122026 as the appropriate source of service information for determining the specific affected airplanes. Conclusion

    Since these changes expand the scope of the original NPRM, we have determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

    Changes to 14 CFR Part 39/Effect on the Proposed AD

    On July 10, 2002, the FAA issued a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's airworthiness directives system. The regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance (AMOCs). These changes are reflected in this supplemental NPRM.

    Changes to Labor Rate

    We have reviewed the figures we have used over the past several years to calculate AD costs to operators. To account for various inflationary costs in the airline industry, we find it necessary to increase the labor rate used in these calculations from $60 per work hour to $65 per work hour. The cost impact information, below, reflects this increase in the specified hourly labor rate.
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    Cost Impact

    There are approximately 195 McDonnell Douglas Model MD11 and ``11F airplanes of the affected design in the worldwide fleet. The FAA estimates that 62 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 1 work hours per airplane to accomplish the proposed inspection, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the inspection proposed by this AD on U.S. operators is estimated to be $4,030, or $65 per airplane.

    The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.

    Regulatory Impact

    The regulations proposed herein would not have a substantial direct effect 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, it is determined that this proposal would not have federalism implications under Executive Order 13132.

    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 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 39AIRWORTHINESS 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:

    McDonnell Douglas: Docket 2000NM32AD.

    Applicability: Model MD11 and 11F airplanes, as listed in Boeing Service Bulletin MD1122026, dated December 19, 2003; certificated in any category.

    Compliance: Required as indicated, unless accomplished previously.

    To prevent electrical shorting of the brake coils of the auto throttle servo (ATS), which could result in smoke in the cockpit and/or passenger cabin, accomplish the following:
    Inspect ATS
    (a) Within 36 months after the effective date of this AD, do an inspection to determine the part number (P/N) of the ATS assembly of the servo assembly of the TCM, per the Accomplishment Instructions of Boeing Service Bulletin MD1122026, dated December 19, 2003. Corrective Actions
    (b) Before further flight after doing the inspection required by paragraph (a) of this AD, do the applicable corrective action(s) specified in ``TableCorrective Actions,'' per Boeing Service Bulletin MD1122026, dated December 19, 2003.
    If Then
    (1) P/N 4059004903 is installed....... Reidentify the TCM assembly. (2) P/N 4059004903 is not installed... Replace the existing ATS assembly of the TCM assembly with a new ATS assembly, and reidentify the TCM assembly; or return TCM assembly to Boeing for modification and reidentification. Parts Installation
    (c) As of the effective date of this AD, no person shall install a thrust control module assembly having part number ABH77601, ABH7760501, ABH7760503, SR117610013, SR117610015, SR117610017, SR112700223, SR117610019, SR112700225, or SR1176100111, on any airplane.
    Alternative Methods of Compliance
    (d) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD.

    Issued in Renton, Washington, on June 30, 2004.
    Kalene C. Yanamura,
    Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
    [FR Doc. 0415760 Filed 71204; 8:45 am]
    BILLING CODE 491013P

    FOR FURTHER INFORMATION CONTACT

    Brett Portwood, Aerospace Engineer, Systems and Equipment Branch, ANM130L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 907124137; telephone (562) 6275350; fax (562) 6275210.