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Proposed Rule

Airworthiness Directives; McDonnell Douglas Model DC-9-10 Series Airplanes; DC-9-20 Series Airplanes; DC-9-30 Series Airplanes; DC-9-40 Series Airplanes; and DC-9-50 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 (FAA), Department of Transportation (DOT).

ACTION:

Supplemental notice of proposed rulemaking (NPRM); reopening of comment period.

SUMMARY:

The FAA is revising an earlier NPRM for an airworthiness directive (AD) that applies to certain McDonnell Douglas transport category airplanes. The original NPRM would have superseded an existing AD that currently requires, among other things, revision of an existing program of structural inspections. The original NPRM proposed to require implementation of a program of structural inspections of baseline structure to detect and correct fatigue cracking in order to ensure the continued airworthiness of these airplanes as they approach the manufacturer's original fatigue design life goal. The original NPRM resulted from a significant number of these airplanes approaching or exceeding the design service goal on which the initial type certification approval was predicated. This new action revises the original NPRM by removing certain service information as acceptable methods of compliance. We are proposing this supplemental NPRM to detect and correct fatigue cracking that could compromise the structural integrity of these airplanes.

DATES:

We must receive comments on this supplemental NPRM by April 3, 2006.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD.

  • DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically.
  • Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your comments electronically. Start Printed Page 11329
  • Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590.
  • Fax: (202) 493-2251.
  • Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Contact Boeing Commercial Airplanes, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024), for service information identified in this proposed AD.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Wahib Mina, Aerospace Engineer, Airframe Branch, ANM-120L, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California 90712-4137; telephone (562) 627-5324; fax (562) 627-5210.

End Further Info End Preamble Start Supplemental Information

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposal. Send your comments to an address listed in the ADDRESSES section. Include the docket number “Docket No. FAA-2005-21779; Directorate Identifier 2002-NM-349-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this supplemental NPRM. We will consider all comments received by the closing date and may amend this supplemental NPRM in light of those comments.

We will post all comments submitted, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this supplemental NPRM. Using the search function of that Web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78), or you may visit http://dms.dot.gov.

Examining the Docket

You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility offices between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the DOT street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the Docket Management System receives them.

Discussion

We proposed to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) with a notice of proposed rulemaking (NPRM) for an AD (the “original NPRM”) for certain McDonnell Douglas transport category airplanes. The original NPRM proposed to supersede AD 96-13-03, amendment 39-9671 (61 FR 31009, June 19, 1996), which applies to all McDonnell Douglas Model DC-9-10, -20, -30, -40, -50, and C-9 (military) series airplanes. (Since the issuance of that AD, the FAA has revised the applicability of the existing AD to identify model designations as published in the most recent type certificate data sheet for the affected models.) The original NPRM was published in the Federal Register on July 8, 2005 (70 FR 39435). The original NPRM proposed to retain the requirements of AD 96-13-03. The original NPRM also proposed to continue to require revision of the FAA-approved maintenance program. The original NPRM also proposed to require implementation of a structural inspection program of baseline structure to detect and correct fatigue cracking in order to ensure the continued airworthiness of airplanes as they approach the manufacturer's original fatigue design life goal. The original NPRM resulted from a significant number of these airplanes approaching or exceeding the design service goal on which the initial type certification approval was predicated. That condition, if not corrected, could result in fatigue cracking that could compromise the structural integrity of these airplanes.

Comments

We have considered the following comments on the original NPRM.

Comments That Resulted in a Change to the Original NPRM

Request To Remove Paragraph (j) of the Original NPRM

One commenter, the manufacturer, points out that the provisions of paragraph (j) of the original NPRM would allow for the use of older outdated versions of Section 2 of Volume II of Boeing Report No. L26-008, “DC-9 All Series, Supplemental Inspection Document (SID),” to satisfy future requirements of the original NPRM. The commenter advises that only the November 2004 revision of Volume II should be allowed for compliance with the proposed new requirements, except for future alternative methods of compliance (AMOCs). Therefore, the commenter requests that paragraph (j) of the original NPRM be removed.

We agree to remove paragraph (j) of the original NPRM for the reason the commenter specified, and we have identified the paragraphs of the supplemental NPRM accordingly.

Request To Revise Certain AMOC Language

The same commenter also requests that paragraph (r) of the original NPRM be revised to extend the time during which certain AMOCs would be acceptable for compliance with the actions required by paragraph (f) of the original NPRM. (Paragraph (f) of the original NPRM is part of the restatement of AD 96-13-03.) The commenter points out that the restatement of the requirements of paragraph (f) of the original NPRM addresses only those revisions of the DC-9 SID that are listed in AD 96-13-03. The commenter concludes that, since the new requirements of paragraph (h) of the original NPRM are required within 12 months of the effective date, any operator using an AMOC to AD 96-13-03 would potentially be out of compliance during the required compliance period of paragraph (h) of the original NPRM.

We agree that paragraph (r) of the original NPRM, now identified as paragraph (p)(4) of the supplemental NPRM, should be revised. We infer that the commenter interprets the requirements of paragraph (h) of the supplemental NPRM to effect the accomplishment of the requirements of paragraph (f) of the supplemental NPRM. This is not the case and in order to clarify the requirements and compliance times of this supplemental NPRM, we have added an explanation in paragraph (f) of the supplemental NPRM specifying that the repetitive inspections required by paragraph (f) of the supplemental NPRM must be repeated until the requirements of paragraph (i) of the supplemental NPRM are accomplished. Consequently, we have revised the language of paragraph (p)(4) of the supplemental NPRM to specify that AMOCs approved previously for alternative inspection procedures and planning requirements of AD 96-13-03 are acceptable for compliance with the actions required by Start Printed Page 11330paragraph (f) of the supplemental NPRM until the requirements, at the times specified in paragraph (i) of the supplemental NPRM, are accomplished.

Request To Clarify Paragraph (m) of the Original NPRM

This same commenter states that paragraph (m) of the original NPRM (that paragraph discusses corrective actions if required) is not clear as to whether or not Authorized Representatives (ARs) may approve alternative methods of compliance (AMOCs).

We agree that paragraph (m) of the original NPRM (identified as paragraph (l) of the supplemental NPRM) should be revised. Since the issuance of the original NPRM, we have determined that the description of the approval of corrective actions such as those specified in paragraph (l) of the supplemental NPRM can be simplified by referring to the “Alternative Methods of Compliance (AMOC),” paragraph (p) of this supplemental NPRM. In addition, our policy is that all future repairs to an airplane must meet damage tolerance requirements of 14 CFR 25.571, amendment 45. The purpose of this policy is to detect and repair fatigue cracks that may occur in a repair before they become another unsafe condition. Therefore, we have also revised the paragraph addressing AMOCs, paragraph (p) of this supplemental NPRM, to include that requirement.

Comments That Did Not Result in a Change to the Original NPRM

Request To Add a New Principal Structural Element (PSE)

One commenter states that the latest revision (November 2002) of the DC-9 SID, Volume I, created a new PSE 53.09.059. The commenter states that the new PSE is not included in the latest revision (November 2004) of Volume II of the SID, and that operators will not be able to complete inspections of the PSE 53.09.059 area without proper definition of that PSE in Volume II. The commenter requests that the “oversight” be corrected with a revision to Volume II of the DC-9 SID, and that the latest revision be specified in the final rule.

We do not agree. We have discussed this issue with the manufacturer, and it has advised us that the DC-9 SID, Volume I, page 1.11, cross-references PSE 53.09.059 to non-destructive inspection (NDI) procedure 53-10-06, with a notation specified on the bottom of the page. The PSE inspection threshold for PSE 53.09.059 specified on page 1.11 states that only sequence 2 of the NDI procedure applies to PSE 53.09.059. Volume 1, Section 4, page 4.10, of the DC-9 SID, also refers to Volume II, procedure 53-10-06. We received no other requests from operators concerning this issue, and the manufacturer is confident that the previous references are sufficient to allow operators to satisfy the SID requirements for this PSE. No change has been made to the supplemental NPRM in this regard.

Request To Consider “Advancing Thresholds”

One commenter requests the original NPRM be revised to “advance the thresholds” prior to the implementation of the final rule (the 100% inspection program) if supported by data collected from the SID sampling program. The commenter states that this would minimize the impact to operators that have inspected any PSE shortly after 1/2Nth, only to find that after that inspection the Nth is increased. The commenter requests that, if a revision to the DC-9 SID is pending, the thresholds should be revised based on service history.

We do not agree to extend the thresholds. The manufacturer has advised us that the service data collected so far is not sufficient to justify extending the threshold values at this time. Additionally, the manufacturer has advised that there are no plans to increase any PSE inspection threshold values specified in Volume I of the DC-9 SID. No change has been made to the supplemental NPRM in this regard.

Request To Revise the Costs of Compliance

One commenter agrees that the original NPRM would require approximately 20 additional hours of labor to inspect each airplane. However, the commenter's data show that the time required to complete the inspections required by existing AD 96-13-03 is 571 labor hours rather than 362 work hours as specified in the existing AD. The commenter bases these labor hours on over 2,000 NDIs performed as part of the SID sampling program. The commenter also notes that the 571 hours of labor do not include time for access, since it performs these inspections at maintenance checks with access already opened. The commenter is requesting that the costs of compliance be revised accordingly.

We do not agree that the Costs of Compliance section needs to be revised. Although we acknowledge that the work hours for the commenter's fleet is more than the work hours estimated in the original NPRM, we also recognize that other operators' fleets may not require the same amount of work hours for the inspections. The work hours specified in the Costs of Compliance section are simply estimates based on the information that we have available from the manufacturer. Because of the differences involved with various airplane configurations and differences in airline maintenance procedures, there may be a significant difference in work hours necessary for operators to accomplish the inspections. Even if additional work hours are necessary for some airplanes, we do not have sufficient information to evaluate the number of airplanes that may be so affected or the number of additional work hours that may be required. Consequently, attempting to estimate work hours for each operator would be futile. No change is necessary to the supplemental NPRM in this regard.

Editorial Change

We have revised this supplemental NPRM to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies.

Additionally, we have determined that accomplishment of the requirements of paragraph (o) of the supplemental AD (inspection/replacement for certain repairs to the fuselage pressure shell in accordance with Boeing Report No. MDC 91K0263, “DC-9/MD-80 Aging Aircraft Repair Assessment Program Document,” Revision 1, dated October 2000), are also acceptable for compliance with the requirements of paragraph (m) of the supplemental AD and have revised paragraph (o) of the supplemental AD accordingly.

Explanation of Change Made to This AD

We have simplified paragraph (l) of the supplemental AD of this AD by referring to the “Alternative Methods of Compliance (AMOCs)” paragraph of this AD for repair methods.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

Certain changes discussed above expand the scope of the original NPRM; therefore, we have determined that it is necessary to reopen the comment period to provide additional opportunity for public comment on this supplemental NPRM. For the purposes of this proposed AD, a PSE is defined as an element that contributes significantly to the carrying of flight, ground or pressurization loads, and the integrity of that element is essential in maintaining Start Printed Page 11331the overall structural integrity of the airplane.

Costs of Compliance

There are about 710 McDonnell Douglas transport category airplanes worldwide of the affected design. This supplemental NPRM would affect about 477 airplanes of U.S. registry, or 26 U.S. airline operators.

The recurring inspection costs, as required by AD-96-13-03, take 362 work hours per airplane, at an average labor rate of $65 per work hour. Based on these figures, the estimated cost of the currently required actions is $11,223,810, or $23,530 per airplane, per inspection cycle.

The incorporation of the revised procedures in this AD action will require approximately 20 additional work hours per operator to accomplish, at an average labor rate of $65 per work hour. Based on these figures, the cost to the 26 affected U.S. operators to incorporate these revised procedures into the SID program is estimated to be $33,800, or $1,300 per operator.

Additionally, the number of required work hours for each proposed inspection (and the SID program), as indicated above, is presented as if the accomplishment of those actions were to be conducted as “stand alone” actions. However, in actual practice, these actions for the most part will be accomplished coincidentally or in combination with normally scheduled airplane inspections and other maintenance program tasks. Further, any costs associated with special airplane scheduling are expected to be minimal.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD 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.

For the reasons discussed above, I certify that the 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. 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.

We prepared a regulatory evaluation of the estimated costs to comply with this supplemental NPRM and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

The Proposed Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

Start Part

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. The Federal Aviation Administration (FAA) amends § 39.13 by removing amendment 39-9671 (61 FR 31009, June 19, 1996) and adding the following new airworthiness directive (AD):

McDonnell Douglas: Docket No. FAA-2005-21779; Directorate Identifier 2002-NM-349-AD.

Comments Due Date

(a) The FAA must receive comments on this AD action by April 3, 2006.

Affected ADs

(b) This AD supersedes AD 96-13-03.

Applicability

(c) This AD applies to all McDonnell Douglas Model DC-9-11, DC-9-12, DC-9-13, DC-9-14, DC-9-15, and DC-9-15F airplanes; DC-9-21 airplanes; DC-9-31, DC-9-32, DC-9-32 (VC-9C), DC-9-32F, DC-9-33F, DC-9-34, DC-9-34F, and DC-9-32F (C-9A, C-9B) airplanes; DC-9-41 airplanes; and DC-9-51 airplanes; certificated in any category.

Unsafe Condition

(d) This AD was prompted by a significant number of these airplanes approaching or exceeding the design service goal on which the initial type certification approval was predicated. We are issuing this AD to detect and correct fatigue cracking that could compromise the structural integrity of these airplanes.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Requirements of AD 96-13-03

Revision of the FAA-Approved Maintenance Inspection Program

(f) Within 6 months after July 24, 1996 (the effective date of AD 96-13-03, amendment 39-9671), replace the FAA-approved maintenance inspection program with a revision that provides for inspection(s) of the principal structural elements (PSEs) defined in McDonnell Douglas Report No. L26-008, “DC-9 Supplemental Inspection Document (SID),” Section 2 of Volume I of McDonnell Douglas Report No. L26-008, “DC-9 Supplemental Inspection Document (SID),” Revision 4, dated July 1993, in accordance with Section 2 of Volume III-95, dated September 1995, of the SID.

Note 1:

Operators should note that certain visual inspections of fleet leader operator sampling PSE's that were previously specified in earlier revisions of Volume III of the SID are no longer specified in Volume III-95 of the SID.

(1) Prior to reaching the threshold (Nth), but no earlier than one-half of the threshold (1/2Nth), specified for all PSE's listed in Volume III-95, dated September 1995, of the SID, inspect each PSE sample in accordance with the non-destructive inspection (NDI) procedures set forth in Section 2 of Volume II, dated July 1993. Thereafter, repeat the inspection for that PSE at intervals not to exceed ΔNDI/2 of the NDI procedure that is specified in Volume III-95, dated September 1995, of the SID, until the requirements of paragraph (i) of this AD are accomplished.

(2) The NDI techniques set forth in Section 2 of Volume II, dated July 1993, of the SID provide acceptable methods for accomplishing the inspections required by this paragraph.

(3) All inspection results (negative or positive) must be reported to McDonnell Douglas, in accordance with the instructions contained in Section 2 of Volume III-95, dated September 1995, of the SID. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

Start Printed Page 11332

Note 2:

Volume II of the SID, dated July 1993, is comprised of the following:

Table 1

Volume designationRevision level shown on volume
Volume II-10/204
Volume II-20/305
Volume II-404
Volume II-504

Note 3:

NDI inspections accomplished in accordance with the following Volume II of the SID provide acceptable methods for accomplishing the inspections required by this paragraph:

Table 2

Volume designationRevision levelDate of revision
Volume II-10/204July 1993.
Volume II-10-203Apr. 1991.
Volume II-10/202Apr. 1990.
Volume II-10/201June 1989.
Volume II-20OriginalNov. 1987.
Volume II-20/305July 1993.
Volume II-20/304Apr. 1991.
Volume II-20/303Apr. 1990.
Volume II-20/302June 1989.
Volume II-20/301Nov. 1987.
Volume II-404July 1993.
Volume II-403Apr. 1991.
Volume II-402Apr. 1990.
Volume II-401June 1989.
Volume II-40OriginalNov. 1987.
Volume II-504July 1993.
Volume II-503Apr. 1991.
Volume II-502Apr. 1990.
Volume II-501June 1989.
Volume II-50OriginalNov. 1987.

(g) Any cracked structure detected during the inspections required by paragraph (f) of this AD must be repaired before further flight, in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.

Note 4:

Requests for approval of any PSE repair that would affect the FAA-approved maintenance inspection program that is required by this AD should include a damage tolerance assessment for that PSE.

New Requirements of This AD

Revision of the Maintenance Inspection Program

(h) Within 12 months after the effective date of this AD, incorporate a revision into the FAA-approved maintenance inspection program that provides for inspection(s) of the PSEs, in accordance with Boeing Report L26-008, “DC-9 All Series, Supplemental Inspection Document (SID),” Volume I, Revision 6, dated November 2002. Unless otherwise specified, all further references in this AD to the “SID” are to Revision 6, dated November 2002.

Non-Destructive Inspections (NDIs)

(i) For all PSEs listed in Section 2 of Volume I of the SID, perform an NDI for fatigue cracking of each PSE in accordance with the NDI procedures specified in Section 2 of Volume II, dated November 2004 of the SID, at the times specified in paragraph (i)(1), (i)(2), or (i)(3) of this AD, as applicable.

(1) For airplanes that have less than three-quarters of the fatigue life threshold (3/4Nth) as of the effective date of the AD: Perform an NDI for fatigue cracking no earlier than one-half of the threshold (1/2Nth) but prior to reaching three-quarters of the threshold (3/4Nth), or within 60 months after the effective date of this AD, whichever occurs later. Inspect again prior to reaching the threshold (Nth) or ΔNDI/2, whichever occurs later, but no earlier than (3/4Nth). Thereafter, after passing the threshold (Nth), repeat the inspection for that PSE at intervals not to exceed ΔNDI/2.

(2) For airplanes that have reached or exceeded three-quarters of the fatigue life threshold (3/4Nth), but less than the threshold (Nth), as of the effective date of the AD: Perform an NDI prior to reaching the threshold (Nth), or within 18 months after the effective date of this AD, whichever occurs later. Thereafter, after passing the threshold (Nth), repeat the inspection for that PSE at intervals not to exceed ΔNDI/2.

(3) For airplanes that have reached or exceeded the fatigue life threshold (Nth) as of the effective date of the AD: Perform an NDI within 18 months after the effective date of this AD. Thereafter, repeat the inspection for that PSE at intervals not to exceed ΔNDI/2.

Note 5:

Volume II of the SID, dated November 2004 comprises the following:

Table 3

Volume designationRevision level shown on volume
Volume II-10/206
Volume II-20/307
Volume II-406
Volume II-506

Discrepant Findings

(j) If any discrepancy (e.g., a PSE cannot be inspected as specified in Volume II of the SID or does not match rework, repair, or modification description in Volume I of the SID) is detected during any inspection required by paragraph (i) of this AD, accomplish the action specified in paragraph (j)(1) or (j)(2) of this AD, as applicable.

(1) If a discrepancy is detected during any inspection performed prior to 3/4Nth or Nth: The area of the PSE affected by the discrepancy must be inspected prior to Nth or within 18 months of the discovery of the discrepancy, whichever is later, in accordance with a method approved by the Manager, Los Angeles ACO, FAA.

(2) If a discrepancy is detected during any inspection performed after Nth: The area of the PSE affected by the discrepancy must be inspected prior to the accumulation of an additional ΔNDI/2, measured from the last non-discrepant inspection finding, or within 18 months of the discovery of the discrepancy, whichever occurs later, in accordance with a method approved by the Manager of the Los Angeles ACO.

Reporting Requirements

(k) All negative, positive, or discrepant (discrepant finding examples are described in paragraph (j) of this AD) findings of the inspections accomplished under paragraph (i) of this AD must be reported to Boeing, at the times specified in, and in accordance with the instructions contained in, Section 4 of Volume I of the SID. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

Corrective Actions

(l) Any cracked structure of a PSE detected during any inspection required by paragraph (i) of this AD must be repaired before further flight in accordance with a method approved by the Manager, Los Angeles ACO, or by using a method approved in accordance with procedures specified in paragraph (p) of this AD. Accomplish follow-on actions described in paragraphs (l)(1), (l)(2), and (l)(3) of this AD, at the times specified.

(1) Within 18 months after repair, perform a damage tolerance assessment (DTA) that defines the threshold for inspection of the repair and submit the assessment for approval.

(2) Before reaching 75% of the repair threshold as determined in paragraph (l)(1) of this AD, submit the inspection methods and repetitive inspection intervals for the repair for approval.

(3) Before the repair threshold, as determined in paragraph (l)(1) of this AD, incorporate the inspection method and repetitive inspection intervals into the FAA-approved structural maintenance or inspection program for the airplane.

Note 6:

For the purposes of this AD, we anticipate that submissions of the DTA of the repair, if acceptable, should be approved within six months after submission.

Note 7:

Advisory Circular AC 25.1529-1, “Instructions for Continued Airworthiness of Structural Repairs on Transport Airplanes,” dated August 1, 1991, is considered to be additional guidance concerning the approval of repairs to PSEs.

Inspection for Transferred Airplanes

(m) Before any airplane that has exceeded the fatigue life threshold (Nth) can be added to an air carrier's operations specifications, a program for the accomplishment of the inspections required by this AD must be established per paragraph (m)(1) or (m)(2) of this AD, as applicable.

(1) For airplanes that have been inspected in accordance with this AD, the inspection of each PSE must be accomplished by the new operator in accordance with the previous operator's schedule and inspection method, or the new operator's schedule and inspection method, at whichever time would result in the earlier accomplishment date for that PSE inspection. The compliance time for Start Printed Page 11333accomplishment of this inspection must be measured from the last inspection accomplished by the previous operator. After each inspection has been performed once, each subsequent inspection must be performed in accordance with the new operator's schedule and inspection method.

(2) For airplanes that have not been inspected in accordance with this AD, the inspection of each PSE required by this AD must be accomplished either prior to adding the airplane to the air carrier's operations specification, or in accordance with a schedule and an inspection method approved by the Manager, Los Angeles ACO. After each inspection has been performed once, each subsequent inspection must be performed per the new operator's schedule.

Inspections Accomplished Before the Effective Date of This AD

(n) Inspections accomplished prior to the effective date of this AD in accordance with Boeing Report No. L26-008, “DC-9 All Series Supplemental Inspection Document (SID),” Volume I, Revision 6, dated November 2002, are acceptable for compliance with the requirements of paragraph (i) of this AD.

Acceptable for Compliance

(o) Boeing Report MDC 91K0263, “DC-9/MD-80 Aging Aircraft Repair Assessment Program Document,” Revision 1, dated October 2000, provides inspection/replacement programs for certain repairs to the fuselage pressure shell. These repairs and inspection/replacement programs are considered acceptable for compliance with the requirements of paragraphs (i), (l), and (m) of this AD for repairs subject to that document.

Alternative Methods of Compliance (AMOCs)

(p)(1) The Manager, Los Angeles ACO, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with CFR 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD, if it is approved by an Authorized Representative for the Boeing Commercial Airplanes Delegation Option Authorization Organization who has been authorized by the Manager, Los Angeles ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane and 14 CFR 25.571, Amendment 45, and the approval must specifically refer to this AD.

(4) AMOCs approved previously for alternative inspection procedures per AD 87-14-07 R1, amendment 39-6019; AD 94-03-01, amendment 39-8807; and AD 96-13-03, amendment 39-9671; are acceptable for compliance with the actions required by paragraph (f) of this AD for inspections performed before the requirements of paragraph (i) are accomplished.

(5) AMOCs approved previously for repairs per AD 87-14-07 R1, amendment 39-6019; AD 94-03-01, amendment 39-8807; and AD 96-13-03, amendment 39-9671; are acceptable for compliance with the requirements of paragraph (l) of this AD.

Start Signature

Issued in Renton, Washington, on February 23, 2006.

Michael J. Kaszycki,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 06-2157 Filed 3-6-06; 8:45 am]

BILLING CODE 4910-13-P