Discussion \n\n\tThe FAA issued a supplemental notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to all Boeing Model 757 airplanes. That supplemental NPRM was published in the Federal Register on August 1, 2007 (72 FR 41963). That supplemental NPRM proposed to require revising the Airworthiness Limitations (AWLs) section of the Instructions for Continued Airworthiness (ICA) by incorporating new limitations for fuel tank systems to satisfy Special Federal Aviation Regulation No. 88 requirements. That supplemental NPRM also proposed to require the initial inspection of certain repetitive inspections specified in the AWLs to phase-in those inspections, and repair if necessary. That supplemental NPRM also proposed to revise the original NPRM by aligning the compliance time for revising the AWLs section with the compliance date of the special maintenance program requirements, updating the listing of applicable airplane maintenance manuals in Appendix 1, and clarifying certain actions. \n\nActions Since Supplemental NPRM Was Issued \n\n\tSince we issued the supplemental NPRM, Boeing has issued Temporary Revision (TR) 09-008, dated March 2008. Boeing TR 09-008 is published as Section 9 of the Boeing 757 Maintenance Planning Document (MPD) Document, D622N001-9, Revision March 2008 (hereafter referred to as "Revision March 2008 of the MPD"). The supplemental NPRM referred to Revision March 2006 of the MPD as the appropriate source of service information for accomplishing the proposed actions. Revision March 2008 of the MPD, among other actions, includes the following changes: \n\n\tRemoves the repetitive task interval of 36,000 flight cycles from AWLs No. 28-AWL-01, No. 28-AWL-03, and No. 28-AWL-14. \n\n\tRevises the task description for AWL No. 28-AWL-01 to harmonize it with AWL No. 28-AWL-02 by removing references to certain station numbers. \n\n\tRevises AWL No. 28-AWL-03 to reflect the new maximum loop resistance values associated with the lightning protection of the unpressurized fuel quantity indicating system (FQIS) wire bundle installations. \n\n\tAccordingly, we have revised paragraphs (f), (g), and (h) of this AD to refer to Revision March 2008 of the MPD. We also have added a new paragraph (j) to this AD specifying that actions done before the effective date of this AD in accordance with Revisions March 2006 through November 2007 of the MPD are acceptable for compliance with the corresponding requirements of paragraphs (g) and (h) of this AD. \n\n\tWe also have removed reference to 36,000 total flight cycles from Table 1 of this AD and revised the initial threshold for accomplishing AWLs No. 28-AWL-01, No. 28-AWL-03, and No. 28-AWL-14 to within 120 months since the date of issuance of the original standard airworthiness certificate or the date of issuance of the original export certificate of airworthiness. \n\n\tOperators should note that we have revised paragraph (g) of thisAD to require incorporating only AWLs No. 28-AWL-01 through No. 28-AWL-24 inclusive. AWL No. 28-AWL-25 was added in Revision October 2006 of the MPD, and AWL No. 28-AWL-26 was added in Revision January 2007 of the MPD. However, as an optional action, operators may incorporate those AWLs as specified in paragraph (g) of this AD. \n\n\tWe have issued a separate NPRM (Docket No. FAA-2007-28598) that, in part, proposes to incorporate AWLs No. 28-AWL-20 and No. 28-AWL-26 into the AWLs section of the ICA. That NPRM was published in the Federal Register on July 9, 2007 (72 FR 37132). We have also issued AD 2008-06- 03, amendment 39-15415 (73 FR 13081, March 12, 2008) that, in part, requires revising the AWLs section of the ICA to incorporate AWLs No. 28-AWL-23, No. 28-AWL-24, and No. 28-AWL-25. Therefore, we have added a new paragraph (k) to this AD specifying that incorporating AWLs No. 28- AWL-23, No. 28-AWL-24, and No. 28-AWL-25 in accordance with paragraph (g) of this AD terminates the action required by paragraph (h)(2) of AD 2008-06-03. \n\nOther Changes Made to This AD \n\n\tWe have revised paragraph (h) of this AD to clarify that the actions identified in Table 1 of this AD must be done at the compliance time specified in that table. Also, for standardization purposes, we have revised this AD in the following ways: \n\n\tWe have added a new paragraph (i) to this AD to specify that no alternative inspections, inspection intervals, or critical design configuration control limitations (CDCCLs) may be used unless they are part of a later approved revision of Revision March 2008 of the MPD, or unless they are approved as an alternative method of compliance (AMOC). Inclusion of this paragraph in the AD is intended to ensure that the AD-mandated airworthiness limitations changes are treated the same as the airworthiness limitations issued with the original type certificate. \n\n\tWe have revised Note 1 of this AD to clarify that an operator must request approval for an AMOC if the operator cannot accomplish the proposed inspections because an airplane has been previously modified, altered, or repaired in the areas addressed by the proposed inspections. \n\n\tWe have revised paragraph (h) of this AD to specify that accomplishing the applicable AWLs in Table 1 of this AD as part of an FAA-approved maintenance program before the applicable compliance time constitutes compliance with the applicable requirements of that paragraph. \n\n\tWe have deleted Appendix 1 from this AD, since Revision March 2008 of the MPD already contains most of the updated information that is listed in Appendix 1 of the NPRM. \n\n\nComments \n\n\tWe provided the public the opportunity to participate in the development of this AD. We have considered the comments received. \n\nRequest To Extend the Task Intervals for Certain AWL Inspections \n\n\tKLM Royal Dutch Airlines, on behalf of several operators, requests that we review a 45-page proposal to align certain airworthiness limitation item (ALI) intervals with the applicable maintenance significant item (MSI) and enhanced zonal analysis procedure (EZAP) intervals for Model 737, 747, 757, 767, and 777 airplanes. The recommendations in that proposal ensure that the ALI intervals align with the maintenance schedules of the operators. Among other changes, the proposal recommends extending certain AWL inspection intervals from 10 years/36,000 flight cycles to 12 years for Model 757 airplanes. \n\n\tWe disagree with KLM's request to extend certain AWL inspection intervals to 12 years. However, as stated previously, we have deleted the 36,000-total-flight-cycle parameter from Table 1 of this AD to correspond with the task intervals specified in Revision March 2008 of the MPD. In developing an appropriate compliance time for this action, we considered the urgency associated with the subject unsafe condition and the practical aspect of accomplishing the required actions within a period of time that corresponds to the normal scheduled maintenance for most affected operators. However, according to the provisions of paragraph (l) of this AD, we might approve requests to adjust the compliance time if the request includes data that prove that the new compliance time would provide an acceptable level of safety. \n\nRequest To Revise the Loop Resistance Values for AWL No. 28-AWL-03 \n\n\tBoeing states that the loop resistance values for AWL No. 28-AWL-03 specified in Revision March 2006 of the MPD are going to be revised, since those values are relevant for production airplanes. Boeing also states that the revised values will be more representative of the expected values for in-service airplanes. Boeing points out that, according to paragraph (h) of the supplemental NPRM, the revised values should be able to be used in accordance with a later revision of the MPD if the revision is approved by the Seattle Aircraft Certification Office (ACO), FAA. \n\tWe agree that operators may use the revised loop resistance values for AWL No. 28-AWL-03 in accordance with Revision March 2008 of the MPD. As stated previously, we have revised this AD accordingly. \n\nRequest To Revise Note 1 \n\n\tBoeing requests that we revise Note 1 of the supplemental NPRM to clarify the need for an AMOC. Boeing states that the current wording is difficult to follow, and that the note is meant to inform operators that an AMOC to the required MPD AWLs might be required if an operator has previously modified, altered, or repaired the areas addressed by the limitations. Boeing requests that we revise Note 1 as follows: \n\n\tAdd the words "according to paragraph (g)" at the end of the first sentence. \n\n\tReplace the words "revision to" with "deviation from" in the last sentence. \n\n\tDelete the words "(g) or" and "as applicable" from the last sentence. \n\n\tAs stated previously, we have simplified the language in Note 1 of this AD for standardization with other similar ADs. The language the commenter requests that we change does not appear in the revised note. Therefore, no additional change to this AD is necessary in this regard. \n\nConclusion \n\n\tWe have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCosts of Compliance \n\n\tThere are about 990 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs, at an average labor rate of $80 per work hour, for U.S. operators to comply with this AD. \n\n\t\t\tEstimated Costs \n\n\nAction\nWork hours\nCost per airplane\nNumber of U.S.-registered airplanes\nFleet cost\nAWLs revision\n8\n$640\n639\n$408,960\nInspections\n8\n$640\n639\n$408,960\n\n\nAuthority for This Rulemaking \n\n\tTitle 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. \n\n\tWe 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. \n\nRegulatory Findings \n\n\tWe have determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government andthe States, or on the distribution of power and responsibilities among the various levels of government. \n\n\tFor the reasons discussed above, I certify that this AD: \n\n\t(1) Is not a "significant regulatory action" under Executive Order 12866; \n\n\t(2) Is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and \n\n\t(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. \n\n\tWe prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\nAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\nSec. 39.13 (Amended) \n\n2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by adding the following new airworthiness directive (AD):