Discussion \n\n\tWe issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Boeing Model 747 airplanes. That NPRM was published in the Federal Register on February 23, 2009 (74 FR 8034). That NPRM proposed to require repetitive inspections for cracking of the fuselage frames in section 41, and corrective actions if necessary. \n\nComments \n\n\tWe gave the public the opportunity to participate in developing this AD. We considered the comments received. \n\nRequests To Delay or Withdraw NPRM \n\n\tJapan Airlines (JAL) asks that we delay issuing the AD until Boeing revises the referenced service information. JAL states that Boeing Alert Service Bulletin 747-53A2753, dated August 28, 2008, does not include access and restoration information for the frame structure inspection. JAL adds that without this information operators are caused an undue burden such as engineering costs and validation. JAL notes that it asked Boeing to develop access and restoration procedures and Boeing agreed to revise the service information to include those procedures. \n\tWe do not agree to delay issuing the AD to wait for revised service information, nor has Boeing informed us of its intent to issue revised service information to include the procedures discussed by the commenter. We have determined that although Boeing Alert Service Bulletin 747-53A2753, dated August 28, 2008, does not include access information for the frame inspection, the majority of operators have their own acceptable access and closing procedures. Although this AD does not mandate a particular method of doing the access and closing procedures, operators can obtain those procedures directly from Boeing if necessary. We have not changed the AD in this regard. \n\tNorthwest Airlines (NWA) would like the NPRM to be withdrawn. NWA states that, in view of the reported damage findings and service information specified in the preamble of the NPRM, there is no justification to support issuing an NPRM which covers a much broader area than where the crack damage was found. NWA states that the inspection for cracking of certain critical regions of the body section 41 structure is also addressed in the supplemental structural inspection document (SSID) inspection program. NWA notes that the SSID inspection program is mandated in previously issued rulemaking and should be used to determine if mandated inspections of the entire body section 41 structure are necessary. NWA adds that additional justification is needed to support mandating those inspections. \n\tAlthough we understand NWA's concern, we do not agree to withdraw the NPRM. We have received several reports of significant cracking of certain fuselage frames in section 41; the cracked frames were found when the airplanes had accumulated relatively low flight cycles. As the fuselage frames on the airplanes affected by this AD are of similar type design, we have determined that all fuselage frames in section 41 are susceptible to the same unsafe condition. \n\tWe are aware that the Boeing Model 747 SSID inspection program, as mandated by AD 2004-07-22 R1, amendment 39-15326 (73 FR 1052, January 7, 2008), requires repetitive inspections of the fuselage frames in section 41. However, analysis by the manufacturer shows that a repetitive inspection interval significantly reduced from the interval specified in the SSID inspection program is required to ensure safety. Rather than revising AD 2004-07-22 R1, which is complex and includes numerous inspections, we have determined that this new AD is appropriate and must be issued without further delay. \n\nRequest To Correct Paragraph Identifiers \n\n\tBoeing requests a correction to the paragraph identifiers specified in paragraph (g) of this AD--i.e., to specify paragraphs (h) and (i) instead of paragraphs (g) and (h). \n\tWe agree with the Boeing comment. The paragraph identifiers were incorrectly identified in the NPRM; therefore, we have changed those identifiers in paragraph (g) of this AD accordingly. \n\nChange to AD Preamble \n\n\tThe Costs of Compliance paragraph has been revised to note that for certain airplanes, it may be necessary to accomplish more than one Part of Boeing Alert Service Bulletin 747-53A2732, dated August 28, 2008, depending on airplane configuration. \n\nConclusion \n\n\tWe reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting the AD with the change described previously. We also determined that this change will not increase the economic burden on any operator or increase the scope of the AD. \n\nCosts of Compliance \n\n\tWe estimate that this proposed AD would affect 165 airplanes of U.S. registry. The following table provides the estimated costs for U.S. operators to comply with this proposed AD. For airplanes on which Boeing Alert Service Bulletin 747-53A2732, datedAugust 28, 2008, must be done, accomplishment of more than one Part of the alert service bulletin may be required, depending on airplane configuration. \n\n\tTable--Estimated Costs\n\n\nInspection\nWork hours\nAverage labor rate per hour\nCost per product\nNumber of U.S-registered airplanes\nFleet cost\nBoeing Alert Service Bulletin 747-53A2732, \nPart 1\n50\n$80\nUp to $4,000, per inspection cycle\n94\nUp to $376,000, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2732, \nPart 2\n650\n$80\nUp to $52,000, per inspection cycle\n94\nUp to $4,888,000, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2732, \nPart 3\n6\n$80\n$480, per inspection cycle\n94\nUp to $45,120, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2732, \nPart 4\n51\n$80\nUp to $4,080, per inspection cycle\n94\nUp to $383,520, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2732, \nPart 5\n11\n$80\nUp to $880, per inspection cycle\n94\nUp to $82,720, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2732, \nPart 6\n52\n$80\nUp to $4,160, per inspection cycle\n94\nUp to $391,040, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2732, \nPart 7\n13\n$80\nUp to $1,040, per inspection cycle\n94\nUp to $97,760, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2732, \nPart 8\n54\n$80\nUp to $4,320, per inspection cycle\n94\nUp to $406,080, per inspection cycle\nBoeing Alert Service Bulletin 747-53A2753\n244\n$80\nUp to $19,520, per inspection cycle\n71\nUp to $1,385,920, per inspection cycle\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\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\tThis 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 and the States, or on the distribution of power and responsibilities among the various levels of government. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a "significant regulatory action'' under Executive Order 12866, \n\t(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979),and \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\tYou can find our regulatory evaluation and the estimated costs of compliance in the AD Docket. \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 FAA amends Sec. 39.13 by adding the following new AD: