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CFR Citation: 14 CFR Part 39

Docket ID: [Docket No. 2001-NM-89-AD]

RIN ID: RIN 2120-AA64

NOTICE: PROPOSED RULES

ACTION: Airworthiness directives:

DOCUMENT ACTION: Notice of proposed rulemaking (NPRM).

SUBJECT CATEGORY: Airworthiness Directives; Boeing Model 777-200 and -300 Series Airplanes

DATES: Comments must be received by October 24, 2003.

DOCUMENT SUMMARY: This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Boeing Model 777200 and 300 series airplanes. For all airplanes, this proposal would require installation of a placard that advises of weight limits for a certain electrical rack, accomplishment of a onetime inspection and records check to determine the amount of weight currently installed in that rack, and removal of equipment from that rack if necessary. For certain airplanes, this proposal also would require a onetime inspection of the clevis end of the vertical tie rods that support the center stowage bins to measure the exposed thread, installation of placards that advise of weight limits for certain other electrical racks, a onetime inspection and records check to determine the amount of weight currently installed in certain other electrical racks, corrective actions, and replacement of the vertical tie rods for the center stowage bins or electrical racks with new improved tie rods, as applicable. This action is necessary to prevent failure of the tie rods supporting certain electrical racks and the center stowage bins, which could cause the racks or stowage bins to fall onto passenger seats below during an emergency landing, impeding an emergency evacuation or injuring passengers. This action is intended to address the identified unsafe condition.

SUMMARY: Boeing,

SUPPLEMENTAL INFORMATION

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:
[sbull] 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.
[sbull] For each issue, state what specific change to the proposed AD is being requested.
[sbull] 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 2001NM89AD.'' 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. 2001NM89AD, 1601 Lind Avenue, SW., Renton, Washington 980554056.

Discussion

The FAA has received a report indicating that, under certain conditions on Boeing Model 777200 and 300 series airplanes, the vertical tie rods that attach the center stowage bins and electrical racks to the airplane structure can break. Multiple broken tie rods could allow the center stowage bins and electrical racks to fall onto the passenger seats below during an emergency landing. This condition, if not corrected, could impede an emergency evacuation or result in injury to passengers.

Explanation of Relevant Service Information

We have reviewed and approved Boeing Service Bulletin 777250144, Revision 1, dated January 10, 2002. For all airplanes, the service bulletin describes procedures for installing a placard showing weight limits for electrical rack E7. For certain airplanes, the service bulletin also describes procedures for additional actions, as follows: [sbull] A onetime inspection of the clevis end of the vertical tie rods that support
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the center stowage bins to measure the exposed thread, and installation of a threaded sleeve if necessary.
[sbull] Replacement of the vertical tie rods that support the center stowage bins with new improved tie rods (including replacing the existing tie rod with a new improved tie rod, torquing the jam nuts, and inspecting through the witness hole to make sure tie rod threads are visible).
[sbull] Replacement of the vertical tie rods that support electrical racks E9, E11, and E13 (including replacing the existing tie rod with a new improved tie rod, replacing an existing tie rod clamp with a new improved tie rod clamp, inspecting certain electrical racks for ``free play,'' adjusting jam nuts if necessary, and inspecting through the witness hole to make sure tie rod threads are visible); as applicable.
[sbull] Installation of placards showing weight limits for electrical racks E9, E11, E13, and E15; as applicable.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would require accomplishment of the applicable actions specified in the service bulletin described previously, except as discussed below under the heading ``Differences Between Proposed Rule and Service Bulletin.'' The proposed AD would also require a onetime records review and inspection to verify that the weight of equipment currently installed in certain electrical racks meets specified weight limits. This records review and inspection would involve determining what extra equipment has been installed in the subject racks of the airplane, performing a detailed inspection to determine that the subject equipment is installed on the airplane, calculating the total weight of the installed equipment, and comparing that total to the weight limit specified on the placard. If the weight of the equipment exceeds the limit specified on the placard, equipment must be removed from the rack to meet the requirement.

In developing an appropriate compliance time for this action, we considered not only the degree of urgency associated with addressing the subject unsafe condition, but the normal maintenance schedules for the majority of affected operators. In consideration of these factors, we have determined that 5 years represents an appropriate interval of time allowable wherein the proposed actions can be accomplished during scheduled maintenance intervals for the majority of affected operators. We find that this will ensure an acceptable level of safety. Clarification of Inspection Types

The service bulletin refers to an inspection of the clevis end of the vertical support tie rod to determine whether a threaded sleeve is required. We find that, since the inspection involves measuring the length of the exposed thread, the procedures for this inspection constitute a detailed inspection. This type of inspection is defined in Note 1 of this proposed AD.

As part of the procedures for replacing the vertical support tie rods, the service bulletin specifies to inspect through the witness hole to ensure that tie rod threads are visible. We find that this inspection constitutes a general visual inspection. This type of inspection is defined in Note 2 of the proposed AD.

Differences Between Proposed AD and Service Bulletin

Operators should note that, although the service bulletin specifies that the manufacturer may be contacted for disposition of certain conditions, this proposal would require the disposition of those conditions per a method approved by the FAA.

Operators also should note that, as explained previously, this proposed AD would require a onetime records review and an inspection that are not included in the service bulletin. We find that these additional actions are necessary to ensure that the weight of equipment currently installed in certain electrical racks is within the limits specified in the placards to be installed per the service bulletin referenced in this proposed AD.

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). Because we have now included this material in part 39, only the office authorized to approve AMOCs is identified in each individual AD.

Change to Labor Rate Estimate

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.

Cost Impact

There are approximately 282 airplanes of the affected design in the worldwide fleet. The FAA estimates that 84 airplanes of U.S. registry would be affected by this proposed AD.

For all airplanes: The records check and inspection to determine the weight currently installed in electrical rack E7 would take approximately 1 work hour per airplane to accomplish, at an average labor rate of $65 per work hour. Based on these figures, the cost impact of this proposed records check and inspection on U.S. operators is estimated to be $5,460, or $65 per airplane.

For all airplanes: It would take approximately 1 work hour to accomplish the proposed installation of a placard specifying weight limits for electrical rack E7, at an average labor rate of $65 per work hour. Required parts would cost approximately $29. Based on these figures, the cost impact of this proposed placard installation on U.S. operators is estimated to be $7,896, or $94 per electrical rack.

For airplanes subject to the records check and inspection to determine the weight currently installed in electrical rack E9, E11, E13, or E15: It would take approximately 1 work hour per electrical rack to accomplish, at an average labor rate of $65 per work hour. Based on these figures, the cost impact of this proposed records check and inspection is estimated to be as much as $260 per airplane.

For airplanes subject to the installation of a placard specifying weight limits for electrical rack E9, E11, E13, or E15: It would take approximately 1 work hour per electrical rack to accomplish, at an average labor rate of $65 per work hour. Required parts would cost approximately $29 per electrical rack. Based on these figures, the cost impact of this proposed installation is estimated to be as much as $376 per airplane.

For airplanes subject to the inspection of the clevis end of the vertical support tie rod for the center stowage bin to measure the exposed thread: It would take as much as 3 work hours per airplane (0.25 work hour per tie rod, with up to 12 subject tie rods per airplane) at an average labor rate of $65 per work hour. Based on these figures, the cost impact of this proposed inspection is estimated to be as much as $195 per airplane.

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For airplanes subject to the replacement of the vertical tie rods that support the center stowage bins: It would take as much as 6 work hours per airplane (0.5 work hour per tie rod, with up to 12 subject tie rods per airplane) at an average labor rate of $65 per work hour. Required parts would cost as much as $3,020 per airplane. Based on these figures, this proposed replacement is estimated to be as much as $3,410 per airplane.

For airplanes subject to the replacement of the vertical tie rods that support the electrical racks: It would take as much as 2 work hours per airplane (0.5 work hour per tie rod with up to 4 subject tie rods per airplane) at an average labor rate of $65 per work hour. Required parts would cost as much as $3,012 per airplane. Based on these figures, this proposed replacement is estimated to be as much as $3,142 per airplane.

The cost impact figures discussed above are 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 proposed 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. The manufacturer may cover the cost of parts associated with certain actions in this proposed AD, subject to warranty conditions. Manufacturer warranty remedies may also be available for labor costs associated with certain actions in this proposed AD. As a result, the costs attributable to the proposed AD may be less than stated above.

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:

Boeing: Docket 2001NM89AD.

Applicability: Model 777200 and 300 series airplanes; line numbers 002 through 151 inclusive, 153 through 157 inclusive, 159 through 195 inclusive, 197 through 211 inclusive, 213 through 237 inclusive, 239 through 241 inclusive, and 243 through 282 inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the vertical tie rods that attach the center stowage bins and electrical racks to the airplane structure, which could cause the center stowage bins and electrical racks to fall onto passenger seats below, impeding an emergency evacuation or injuring passengers, accomplish the following:
Inspection To Determine Weight and Placard Installation
(a) For airplanes in the groups listed in the table under paragraph 3., Part 1, paragraph E., of the Accomplishment
Instructions of Boeing Service Bulletin 777250144, Revision 1, dated January 10, 2002: Within 5 years after the effective date of this AD, do the applicable actions in paragraphs (a)(1) and (a)(2) of this AD.
(1) Install placards that show weight limits for electrical racks E7, E11, and E15; as applicable; per the Accomplishment Instructions of the service bulletin.
(2) For each electrical rack on which a placard was installed per paragraph (a)(1) of this AD: Perform a onetime inspection and records check to determine the weight of equipment installed in that electrical rack. This records review and inspection must include determining what extra equipment has been installed, if any, in the subject rack of the airplane, performing a detailed inspection to determine that this equipment is installed on the airplane, calculating the total weight of the installed equipment, and comparing that total to the weight limit specified on the placard installed per paragraph (a)(1) of this AD. If the weight is outside the limits specified in the placard to be installed per the service bulletin, before further flight, remove equipment from the rack to meet the weight limit specified in the placard.

Note 1: For the purposes of this AD, a detailed inspection is defined as: ``An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally
supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.''
Inspection To Measure Exposed Thread
(b) For airplanes in the groups listed in the table under paragraph 3., Part 1, paragraph C., of the Accomplishment
Instructions of Boeing Service Bulletin 777250144, Revision 1, dated January 10, 2002: Within 5 years after the effective date of this AD, perform a detailed inspection of the clevis end of the vertical support tie rod for the center stowage bin to measure the exposed thread, per the Accomplishment Instructions of the service bulletin. If the measurement of the exposed thread is outside the limits specified in Figure 2 of the service bulletin, before further flight, perform all corrective actions specified in steps 2 through 15 inclusive of Figure 2 of the service bulletin. Perform the corrective actions per the Accomplishment Instructions of the service bulletin, except as provided by paragraph (e) of this AD. Replacement of Tie Rods for Center Stowage Bin
(c) For airplanes in Group 21, as listed in the Airplane Group column of the table under paragraph 3., Part 1, paragraph D., of the Accomplishment Instructions of Boeing Service Bulletin 777250144, Revision 1, dated January 10, 2002: Within 5 years after the effective date of this AD, replace the vertical support tie rods for the center stowage bin with new improved tie rods (including replacing the existing tie rod with a new improved tie rod, torquing the jam nuts, performing a general visual inspection through the witness hole to make sure tie rod threads are visible, and making any applicable adjustment of the clevis) by doing all actions specified in steps 1 through 8 of Figure 3 of the service bulletin. Do these actions per the Accomplishment Instructions of the service bulletin, except as provided by paragraph (e) of this AD. Any required adjustment of the clevis must be done before further flight.

Note 2:

For the purposes of this AD, a general visual inspection is defined as: ``A visual examination of an interior or exterior [[Page 53058]]
area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked.''
Inspection To Determine Weight, Tie Rod Replacement, and Placard Installation
(d) For airplanes in the groups listed in the table under paragraph 3., Part 1, paragraph F., of the Accomplishment
Instructions of Boeing Service Bulletin 777250144, Revision 1, dated January 10, 2002: Do the actions in paragraphs (d)(1), (d)(2), and (d)(3) of this AD.
(1) Within 5 years after the effective date of this AD, replace the vertical support tie rods for electrical racks E9, E11, and E13 (including replacing the existing tie rods with new improved tie rods, replacing an existing tie rod clamp with a new improved tie rod clamp, performing a freeplay inspection of certain electrical racks, adjusting jam nuts as applicable, performing a general visual inspection through the witness hole to make sure tie rod threads are visible, and making any applicable adjustment to ensure tie rod threads are visible) by doing all actions specified in Figures 5, 6, 7, and 9 of the service bulletin; as applicable. Do these actions per the Accomplishment Instructions of the service bulletin. Any required adjustment must be done before further flight.
(2) Before further flight after accomplishing paragraph (d)(1) of this AD, install placards that show weight limits for electrical racks E9, E11, and E13; as applicable; per the Accomplishment Instructions of the service bulletin.
(3) For each electrical rack on which a placard was installed per paragraph (d)(2) of this AD: Before further flight after accomplishing paragraphs (d)(1) and (d)(2) of this AD, perform a onetime inspection and records check to determine the weight of equipment installed in that electrical rack. This records review and inspection must include determining what, if any, extra equipment has been installed in the subject racks of the airplane, performing a detailed inspection to determine that this equipment is installed on the airplane, calculating the total weight of the installed equipment, and comparing that total to the weight limit specified on the placard installed per paragraph (d)(2) of this AD. If the weight is outside the limits specified in the placard, before further flight, remove equipment from the rack to meet the weight limit specified in the placard.
Exception to Service Bulletin Instructions
(e) Where the service bulletin specifies to contact Boeing for appropriate action, before further flight, repair per a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA; or per data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the Manager, Seattle ACO, to make such findings. For a repair method to be approved, the approval must specifically reference this AD.
Alternative Methods of Compliance
(f) In accordance with 14 CFR 39.19, the Manager, Seattle ACO, is authorized to approve alternative methods of compliance for this AD.

Issued in Renton, Washington, on September 2, 2003. Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. 0322890 Filed 9803; 8:45 am]
BILLING CODE 491013P

FOR FURTHER INFORMATION CONTACT Robert Kaufman, Aerospace Engineer, Cabin Safety and Environmental Systems Branch, ANM150S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 980554056; telephone (425) 9176433; fax (425) 9176590.