A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to all Boeing Model 747SP, 747SR, 747-100, -100B, -100B SUD, -200B, -200C, -200F, and -300 series airplanes, was published as a supplemental notice of proposed rulemaking (NPRM) in the Federal Register on August 23, 2005 (70 FR 49207). That action proposed to require modification of the escape slide/raft pack assembly and cable release sliders, as applicable. \n\nComments \n\n\tInterested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received. \n\nRequest To Change Paragraph (a)(1) \n\n\tOne commenter, the manufacturer, disagrees with the language specified in paragraph (a)(1) of the supplemental NPRM as written. The commenter reiterates that paragraph and states that it disagrees with the content. The commenter states that, if Boeing Service Bulletin 747- 25-2666, Revision 2, dated April 24, 2003; and Goodrich Service Bulletin 25-238, Revision 1, dated January 31, 2003; have been incorporated, the Door 3 ramp slide pack (two-piece slide) will have been replaced with a one-piece slide pack, which does not have the cable assemblies addressed by Boeing Service Bulletin 747-25-3274, Revision 3, dated December 16, 2004 (referenced in the supplemental NPRM for accomplishing certain actions). The one-piece slides installed by Goodrich Service Bulletin 25-238 are specified in that service bulletin. \n\n\tWe agree with the commenter and have revised paragraph (a)(1) (re- identified as paragraph (a)(2) of the final rule) as follows: "For airplanes on which the modification of Door 3, as specified in Boeing Special Attention Service Bulletin 747-25-2666, Revision 2; and Goodrich Service Bulletin 25-238, Revision 1; has been accomplished: No further action is required for Door 3 only.'' \n\nRequest To Exclude Certain Airplanes From the Applicability \n\n\tOne commenter asks that we change the applicability section specified in the supplemental NPRM. The commenter states that not all the airplanes listed in the applicability section are equipped with the affected escape slide/raft pack assembly components. The commenter notes that it operates several Model 747-100 series airplanes that do not have the affected equipment installed. The commenter adds that those airplanes were originally designed and manufactured with the cool gas generator escape slide inflation system, which does not include the affected escape slide/raft pack assembly components. Additionally, Boeing Special Attention Service Bulletin 747-25-3274 does not include those airplanes in the effectivity, nor does it include procedures for those airplanes. The commenter asks that the applicability section be changed to be similar to that in AD 2004-03-17, amendment 39-13461 (69 FR 6536, February 11, 2004), which includes both the affected airplane models and those equipped with affected components. \n\n\tWe agree with the commenter and have changed the applicability section in this AD to exclude those airplanes that do not have the affected equipment installed, as follows: "Model 747SP, 747SR, 747- 100, -100B, -100B SUD, -200B, -200C, -200F, and -300 series airplanes; certificated in any category; equipped with an escape slide/raft pack assembly; as identified in Boeing Special Attention Service Bulletin 747-25-3274, Revision 3, dated December 16, 2004.'' \n\n\tAnother commenter asks that the final rule include a statement to the effect that Model 747 airplanes converted to the all-cargo configuration by any FAA-approved modification are excluded from accomplishing the modification of the slide required by the AD on any main door that has had the slide removed. The commenter suggests that this would reduce the number of requests submitted to the FAA for alternative methods of compliance (AMOC), thus reducing the use of FAA resources. The commenter also states that airplanes on which the escape slides for the upper deck crew door have been removed, in accordance with Supplemental Type Certificate (STC) ST01539SE, should be excluded from the applicability section of the AD. \n\n\tWe agree with the commenter that airplanes with an FAA-approved modification of the main doors that have the slides removed are not affected by the unsafe condition and should not be subject to this AD. Therefore, we have changed the applicability section in this AD to specify airplanes "equipped with an escape slide raft/pack assembly'; which, in turn, excludes airplanes on which the escape slides for the upper deck crew door have been removed in accordance with STC ST01539SE. \n\nRevised Service Information \n\n\tAfter the supplemental NPRM was issued, Boeing released Service Bulletin 747-25-3274, Revision 4, dated February 23, 2006. We have reviewed the service bulletin and it is substantially similar to Revision 3, which was referred to in the supplemental NPRM as the acceptable source of service information for accomplishing the actions specified in paragraph (a)(1). We have revised paragraph (a)(1) of this AD to refer to Revision 4 of the service bulletin as the acceptable source of service information for accomplishing the actions, and to give credit for accomplishing the actions specified in Revision 3 before the effective date of this AD. \n\nClarification of AMOC Paragraph \n\n\tWe have revised this action to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies. \n\nConclusion \n\n\tAfter careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes previously described. These changes will neither increase the economic burden on any operator nor increase the scope of the AD. \n\nCost ImpactThere are approximately 592 airplanes of the affected design in the worldwide fleet. We estimate that 187 airplanes of U.S. registry will be affected by this AD. \n\n\tIt will take approximately 2 work hours per escape slide to accomplish the new modification of the escape slide/raft pack assembly, at an average labor rate of $65 per work hour. Required parts will cost between $8,354 and $30,688 per airplane. Based on these figures, the cost impact of the modification of the escape slide/raft pack assembly required by this AD on U.S. operators is estimated to be between $1,586,508 and $5,762,966, or between $8,484 and $30,818 per airplane. \n\n\tShould an operator be required to accomplish the overhaul of the cable release sliders, it will take approximately 2 work hours to accomplish the overhaul, at an average labor rate of $65 per work hour. Required parts cost will be negligible. Based on these figures, the cost impact of the overhaul of the cable release sliders in this AD on U.S.operators is estimated to be $130 per escape slide and $260 per airplane. \n\n\tShould an operator be required to accomplish the replacement of the cable release sliders, it will take approximately 1 work hour to accomplish the replacement, at an average labor rate of $65 per work hour. Required parts will cost approximately $2,940 per escape slide. Based on these figures, the cost impact of the replacement of the cable release sliders in this AD on U.S. operators is estimated to be $3,005 per escape slide or $6,010 per airplane. \n\n\tThe cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this 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 asthe time required to gain access and close up, planning time, or time necessitated by other administrative actions. \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 Impact \n\n\tThe regulations adopted herein 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. Therefore, it is determined that this final rule does not have federalism implications under Executive Order 13132. \n\n\tFor the reasons discussed above, I certify that this action (1) is not a "significant regulatory action'' under Executive Order 12866; (2) is not a "significant rule'' under 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption ADDRESSES.List 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, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new airworthiness directive: