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Proposed Rule

Airworthiness Directives; Boeing Model 727, 737-100, 737-200, and 737-200C Series Airplanes

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

AGENCY:

Federal Aviation Administration, (DOT).

ACTION:

Supplemental notice of proposed rulemaking; reopening of comment period.

SUMMARY:

This document revises an earlier proposed airworthiness directive (AD), applicable to certain Boeing Model 727, 737-100, 737-200, and 737-200C series airplanes. That proposed AD would have required a one-time inspection to determine the part number of hydraulic accumulators installed in various areas of the airplane, and follow-on corrective actions if necessary. This new action revises the proposed rule by adding an inspection of an additional area of the airplane, and follow-on corrective actions if necessary. This new action also clarifies what actions are necessary for accumulators with certain part numbers. This action is necessary to prevent high-velocity separation of a barrel, piston, or end cap from a hydraulic accumulator. Such separation could result in injury to personnel in the accumulator area; loss of cabin pressurization; loss of affected hydraulic systems; or damage to plumbing, electrical installations, or structural members. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by February 7, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-19-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2002-NM-19-AD” in the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from Boeing Commercial Airplane Group, PO Box 3707, Seattle, Washington 98124-2207. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

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FOR FURTHER INFORMATION CONTACT:

Barbara Mudrovich, Aerospace Engineer, Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2983; fax (425) 227-1181.

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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 action may be changed in light of the comments received.

Submit comments using the following format:

  • Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues. Start Printed Page 312
  • 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 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 action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2002-NM-19-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. 200-NM-19-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

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 Boeing Model 727, 737-100, 737-200, and 737-200C series airplanes, was published as a notice of proposed rulemaking (NPRM) in the Federal Register on May 20, 2002 (67 FR 35464). That NPRM would have required a one-time inspection to determine the part number of hydraulic accumulators installed in various areas of the airplane, and follow-on corrective actions if necessary. That NPRM was prompted by reports of several incidents on various Boeing Model 747 series airplanes, and one incident on a Boeing Model 737-200 series airplane, in which aluminum end caps on hydraulic accumulators have fractured. That condition, if not corrected, could result in high-velocity separation of a barrel, piston, or end cap from a hydraulic accumulator. Such separation could result in injury to personnel in the accumulator area; loss of cabin pressurization; loss of affected hydraulic systems; or damage to plumbing, electrical installations, or structural members.

Comments

Due consideration has been given to the comments received in response to the NPRM. Certain comments, as discussed below, have resulted in changes to the proposed AD.

Support for the Proposed AD

One commenter concurs with the proposed AD, and another commenter states that it has no technical objection to the proposed AD because it does not operate any affected airplanes.

Include Additional Requirements

One commenter, the airplane manufacturer, requests that the FAA revise the proposed AD to include additional requirements. The commenter points out that Boeing Special Attention Service Bulletin 737-78-1068, Revision 1, dated March 1, 2001, addresses a hydraulic accumulator, Boeing part number (P/N) BACA11E2 (vendor P/N 2660472-2 or 2660472M2), installed in the thrust reverser actuation system on certain Boeing Model 737-100, -200, and “200C series airplanes. Boeing Special Attention Service Bulletin 737-32-1334, Revision 1, dated March 1, 2001, which is one of the service bulletins that would be required by the proposed AD, addresses the same hydraulic accumulator as installed in the landing gear brake system.

The FAA concurs with the commenter's request. We have reviewed and approved Boeing Special Attention Service Bulletin 737-78-1068, Revision 1. That service bulletin describes procedures for a one-time inspection to determine the part number of the hydraulic accumulator in the thrust reverser actuation system, and follow-on corrective actions. Corrective actions include replacing the existing hydraulic accumulator with an improved or modified accumulator having stainless steel end caps. The service bulletin refers to Parker Service Bulletin 2660472-29-63, dated December 12, 2000, as the appropriate source of service information for modification of the hydraulic accumulator.

We have added a new paragraph, paragraph (e), to this supplemental NPRM to propose to require accomplishment of the actions in Boeing Special Attention Service Bulletin 737-78-1068, Revision 1. Also, we have added Note 6 to this supplemental NPRM to state that the service bulletin refers to Parker Service Bulletin 2660472-29-63 as the appropriate source of service information for modification of the hydraulic accumulator.

Remove Requirement to Replace Certain Accumulators

One commenter requests that we revise paragraphs (b)(2) and (c)(2) of the proposed AD to remove certain P/Ns. The commenter points out that the accumulators with those particular P/Ns have steel end caps. The only necessary action is installation of new accumulator clamps and mounting hardware. The commenter suggests that we move the specified P/Ns to a separate paragraph to clarify that replacement of these accumulators with new accumulators is not necessary.

We concur that moving the specified part numbers to separate paragraphs would more clearly state our intent. We acknowledge that the P/Ns identified by the commenter do not need to be replaced. Therefore, we have revised paragraphs (b)(2) and (c)(2) of this supplemental NPRM to remove the subject P/Ns, and have included those P/Ns in new paragraphs (b)(3) and (c)(3) of this supplemental NPRM. Those paragraphs would require replacing existing accumulator clamps and mounting hardware with stronger accumulator clamps and mounting hardware, per the referenced service bulletin.

Remove a Certain Accumulator

The same commenter requests that we remove a certain accumulator, P/N BACA11E4S, from paragraphs (b)(2) and (c)(2) of the proposed AD. The commenter states that, while that accumulator has aluminum end caps, the end caps are thicker and the design of the accumulator is different from that of the accumulators that have failed in service. The commenter notes that there have been no reported failures of that accumulator. The commenter asserts that no action is necessary if this accumulator is installed.

We partially concur. We do not agree that no action is necessary if an accumulator with the subject P/N is installed. However, if an accumulator with the subject P/N is installed, it is necessary only to replace existing accumulator clamps and mounting hardware with new, stronger clamps and hardware. Therefore, we have removed the subject P/N from paragraphs (b)(2) and (c)(2) of the proposed AD and instead have included it in new paragraphs (b)(3) and (c)(3) of this supplemental NPRM, which were described previously.

Explanation of Additional Changes

Because the language in Notes 2 and 6 of the proposed AD is regulatory in nature, those notes have been Start Printed Page 313redesignated as paragraphs (f) and (g) of this supplemental NPRM. Remaining notes have been renumbered accordingly.

Also, paragraphs (a), (b), (c), (d), and (e), have been revised in this supplemental NPRM to clarify that we do not intend to require completing the Evaluation Form attached to the service bulletin.

Conclusion

Since certain changes described previously expand the scope of the originally proposed AD, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.

Cost Impact

There are approximately 1,832 Model 727 series airplanes and 1,033 Model 737 series airplanes of the affected design in the worldwide fleet. The FAA estimates that 1,294 Model 727 series airplanes and 376 Model 737 series airplanes of U.S. registry would be affected by this proposed AD.

We estimate that it would take approximately 1 work hour per airplane to accomplish the proposed one-time inspection, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed one-time inspection on U.S. operators is estimated to be $100,200, or $60 per airplane.

Cost Impact: On-Condition Actions

For an airplane subject to the replacement per Boeing Service Bulletin 727-29-0064, we estimate that it would take approximately 5 work hours per accumulator (two hydraulic system accumulators per airplane), at an average labor rate of $60 per work hour. Required parts would cost between $1,400 (new part) and $2,810 (vendor-modified part) per accumulator. Based on these figures, the cost impact of this replacement, if necessary, would be between $1,700 and $3,110 per accumulator.

For an airplane subject to the replacement of both the mounting clamps and hardware and the hydraulic accumulator per Boeing Service Bulletin 727-32-0410, we estimate that it would take approximately 6 work hours per airplane to accomplish (one landing gear brake accumulator per airplane), at an average labor rate of $60 per work hour. Required parts would cost between $2,500 (new part) and $3,975 (vendor-modified part) per airplane. Based on these figures, the cost impact of this replacement, if necessary, would be between $2,860 and $4,335 per airplane.

For an airplane subject to the replacement of both the mounting clamps and hardware and the hydraulic accumulator per Boeing Service Bulletin 727-52-0148, we estimate that it would take approximately 6 work hours per airplane (one aft airstairs hydraulic accumulator per airplane) to accomplish, at an average labor rate of $60 per work hour. Required parts would cost between $2,500 (new part) and $3,975 (vendor-modified part) per airplane. Based on these figures, the cost impact of this replacement, if necessary, would be between $2,860 and $4,335 per airplane.

For an airplane subject to the replacement per Boeing Service Bulletin 737-32-1334, we estimate that it would take approximately 5 work hours per accumulator (two landing gear hydraulic brake accumulators per airplane) to accomplish, at an average labor rate of $60 per work hour. Required parts would cost between $2,175 (operator-modified part) and $2,410 (vendor-modified part) per accumulator. Based on these figures, the cost impact of this replacement, if necessary, would be between $2,475 and $2,710 per accumulator.

For an airplane subject to the replacement per Boeing Special Attention Service Bulletin 737-78-1068, we estimate that it would take approximately 5 work hours per accumulator to accomplish, at an average labor rate of $60 per work hour. Required parts would cost between $2,175 (operator-modified part) and $2,410 (vendor-modified part) per accumulator. Based on these figures, the cost impact of this replacement, if necessary, would be between $2,475 and $2,710 per accumulator.

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.

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.

Start List of Subjects

List of Subjects in 14 CFR Part 39

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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:

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PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Boeing: Docket 2002-NM-19-AD.

Applicability: Model 727 series airplanes, line numbers (L/N) 1 through 1832 inclusive; and Model 737-100, -200, and -200C series airplanes, L/N 1 through 1033 inclusive; 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 (j) 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.

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Compliance: Required as indicated, unless accomplished previously.

To prevent high-velocity separation of a barrel, piston, or end cap from a hydraulic accumulator, which could result in injury to personnel in the accumulator area; loss of cabin pressurization; loss of affected hydraulic systems; or damage to plumbing, electrical installations, or structural members; accomplish the following:

Inspection/Corrective Action: Service Bulletin 727-29-0064

(a) For airplanes listed in Boeing Special Attention Service Bulletin 727-29-0064, Revision 1, dated May 3, 2001: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, do a one-time inspection to determine the part numbers (P/Ns) of hydraulic accumulators in hydraulic systems “A” and “B,” per the Accomplishment Instructions of the service bulletin, excluding the Evaluation Form.

(1) If no hydraulic accumulator with Parker P/N 1356-603303 is installed: No further action is required by this paragraph.

(2) If any hydraulic accumulator with Parker P/N 1356-603303 is installed: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, replace the subject hydraulic accumulator with a new or modified accumulator, per the service bulletin, excluding the Evaluation Form.

Note 2:

Boeing Special Attention Service Bulletin 727-29-0064, Revision 1, refers to Parker Service Bulletin 1356-603303-29-60, dated January 9, 2001, as the appropriate source of service information for modification of the hydraulic accumulators that are subject to replacement per Service Bulletin 727-29-0064, Revision 1.

Inspection/Corrective Action: Service Bulletin 727-32-0410

(b) For airplanes listed in Boeing Special Attention Service Bulletin 727-32-0410, Revision 2, dated January 24, 2002: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, do a one-time inspection to determine the P/N of the hydraulic accumulator in the landing gear brake system, per the service bulletin, excluding the Evaluation Form.

(1) If no hydraulic accumulator with P/N 1356-603399, 3780078-104, BACA11E4S, BACA11E4SA, 60857-4-1, or BACA11E4 (vendor P/N 2660472-4 or 2660472M4) is installed: No further action is required by this paragraph.

(2) If any hydraulic accumulator with P/N 1356-603399 or BACA11E4 (vendor P/N 2660472-4 or 2660472M4) is installed: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, replace existing accumulator clamps and mounting hardware with new, stronger accumulator clamps and mounting hardware, and replace the subject hydraulic accumulator with a new or modified accumulator, per the service bulletin, excluding the Evaluation Form.

(3) If any hydraulic accumulator with P/N 3780078-104, BACA11E4S, BACA11E4SA, or 60857-4-1 is installed: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, replace existing accumulator clamps and mounting hardware with new, stronger accumulator clamps and mounting hardware, per the service bulletin, excluding the Evaluation Form.

Note 3:

Boeing Special Attention Service Bulletin 727-32-0410, Revision 2, refers to Parker Service Bulletins 1356-603399-29-61 and 2660472-29-63, both dated December 12, 2000, as the appropriate sources of service information for modification of the hydraulic accumulators that are subject to replacement per Service Bulletin 727-32-0410, Revision 2.

Inspection/Corrective Action: Service Bulletin 727-52-0148

(c) For airplanes listed in Boeing Special Attention Service Bulletin 727-52-0148, Revision 2, dated January 24, 2002: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, do a one-time inspection to determine the P/N of the hydraulic accumulator in the aft airstairs, per the service bulletin, excluding the Evaluation Form.

(1) If no hydraulic accumulator with P/N 1356-603399, 3780078-104, BACA11E4S, BACA11E4SA, 60857-4-1, or BACA11E4 (vendor P/N 2660472-4 or 2660472M4) is installed: No further action is required by this paragraph.

(2) If any hydraulic accumulator with P/N 1356-603399 or BACA11E4 (vendor P/N 2660472-4 or 2660472M4) is installed: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, replace existing accumulator clamps and mounting hardware with new, stronger accumulator clamps and mounting hardware, and replace the subject hydraulic accumulator with a new or modified accumulator, per the service bulletin, excluding the Evaluation Form.

(3) If any hydraulic accumulator with P/N 3780078-104, BACA11E4S, BACA11E4SA, or 60857-4-1 is installed: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, replace existing accumulator clamps and mounting hardware with new, stronger accumulator clamps and mounting hardware, per the service bulletin, excluding the Evaluation Form.

Note 4:

Boeing Special Attention Service Bulletin 727-52-0148, Revision 2, refers to Parker Service Bulletins 1356-603399-29-61 and 2660472-29-63, both dated December 12, 2000, as the appropriate sources of service information for modification of the hydraulic accumulators that are subject to replacement per Service Bulletin 727-52-0148, Revision 2.

Inspection/Corrective Action: Service Bulletin 737-32-1334

(d) For airplanes listed in Boeing Special Attention Service Bulletin 737-32-1334, Revision 1, dated March 1, 2001: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, do a one-time inspection to determine the P/Ns of the hydraulic accumulators in the landing gear brake system, per the service bulletin, excluding the Evaluation Form.

(1) If no hydraulic accumulator with P/N BACA11E2 (vendor P/N 2660472-2 or 2660472M2) is installed: No further action is required by this paragraph.

(2) If any hydraulic accumulator with P/N BACA11E2 (vendor P/N 2660472-2 or 2660472M2) is installed: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, replace the subject hydraulic accumulator with a new or modified accumulator, per the service bulletin, excluding the Evaluation Form.

Note 5:

Boeing Special Attention Service Bulletin 737-32-1334, Revision 1, refers to Parker Service Bulletin 2660472-29-63, dated December 12, 2000, as the appropriate source of service information for modification of the hydraulic accumulators that are subject to replacement per Service Bulletin 737-32-1334, Revision 1.

Inspection/Corrective Action: Service Bulletin 737-78-1068

(e) For airplanes listed in Boeing Special Attention Service Bulletin 737-78-1068, Revision 1, dated March 1, 2001: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, do a one-time inspection to determine the P/Ns of the hydraulic accumulators in the thrust reverser actuation system, per the service bulletin, excluding the Evaluation Form.

(1) If no hydraulic accumulator with P/N BACA11E2 (vendor P/N 2660472-2 or 2660472M2) is installed: No further action is required by this paragraph.

(2) If any hydraulic accumulator with P/N BACA11E2 (vendor P/N 2660472-2 or 2660472M2) is installed: Within 18 months or 6,000 flight hours after the effective date of this AD, whichever is first, replace the subject hydraulic accumulator with a new or modified accumulator, per the service bulletin, excluding the Evaluation Form.

Note 6:

Boeing Special Attention Service Bulletin 737-78-1068, Revision 1, refers to Parker Service Bulletin 2660472-29-63, both dated December 12, 2000, as the appropriate source of service information for modification of the hydraulic accumulators that are subject to replacement per Service Bulletin 737-78-1068, Revision 1.

Inspections Accomplished Per Previous Issues of Service Bulletins

(f) Inspections and replacements accomplished before the effective date of this AD per Boeing Special Attention Service Bulletin 727-29-0064, dated June 8, 2000, are considered acceptable for compliance with the corresponding action required by paragraph (a) of this AD.

(g) Inspections and replacements accomplished before the effective date of this AD per Boeing Special Attention Service Bulletin 737-32-1334, dated May 11, 2000, are considered acceptable for compliance with the corresponding actions required by paragraph (d) of this AD.

(h) Inspections and replacements accomplished before the effective date of this AD per Boeing Special Attention Service Bulletin 737-78-1068, dated June 8, 2000, are considered acceptable for compliance Start Printed Page 315with the corresponding action required by paragraph (e) of this AD.

Part Installation

(i) As of the effective date of this AD, no one may install a hydraulic accumulator with a P/N listed in paragraph (a)(2), (b)(2), (c)(2), (d)(2), or (e)(2) of this AD on any airplane.

Alternative Methods of Compliance

(j) 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. 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 7:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

Special Flight Permits

(k) Special flight permits may be issued in accordance with §§ 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.

Start Signature

Issued in Renton, Washington, on December 24, 2002.

Vi L. Lipski,

Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 03-23 Filed 1-2-03; 8:45 am]

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