Discussion \n\n\n\tWe issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to the specified products. The NPRM published in the Federal Register on December 20, 2012 (77 FR 75402). The NPRM proposed to require doing wiring changes and installing a \n\n((Page 72565)) \n\nnew air/ground relay to the battery charger system. \n\nComments \n\n\n\tWe gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal (77 FR 75402, December 20, 2012) and the FAA's response to each comment. \n\nSupport for the NPRM (77 FR 75402, December 20, 2012) \n\n\n\tThe Air Line Pilots Association International (ALPA) stated that it supports the NPRM (77 FR 75402, December 20, 2012). \n\tBoeing stated that it concurs with the contents of the NPRM (77 FR 75402, December 20, 2012). \n\tThe National Transportation Safety Board stated that it supports the NPRM (77 FR 75402, December 20, 2012), and that, in conjunction with the procedural changes recommended by the board and implemented by Boeing, the NPRM will provide an additional margin of safety by requiring modifications to the airplane that will allow flightcrews to manage the electrical system more effectively in the event of a relay failure that results in a loss of power to the standby bus. \n\nRequest To Mandate Quick Reference Handbook (QRH) Change \n\n\n\tALPA requested we ensure that operators adopt the QRH procedural changes that have been implemented by Boeing. ALPA stated that incorporating the QRH procedural changes would help to ensure that an event similar to the event that prompted the NPRM (77 FR 75402, December 20, 2012) does not occur during the 60-month compliance time. \n\tWe partially agree with the commenter's request. We agree that incorporating the QRH change prior to implementing the design change helps mitigate the unsafe condition. We disagree with mandating incorporation of the QRH change. We have evaluated the risk and have determined that accomplishing this final rule within the required compliance time adequately addresses the unsafe condition without the need for any additional interim actions. We have determined this AD action is appropriate based on the probability of occurrence, without requiring that operators incorporate the temporary procedural changes prior to incorporating the required design changes. We have not changed this final rule in this regard. \n\nRequest To Specify Alternative Relay Locations \n\n\n\tUnited Airlines (UAL) requested that we specify alternate locations for the new air/ground relay in the P36 panel versus the location specified in Figure 15, Sheet 2, of Boeing Special Attention Service Bulletin 757-24-0132, Revision 1, dated June 19, 2012 (which is the service information referenced in the NPRM (77 FR 75402, December 20, 2012)). UAL stated that operators will need to apply for alternative methods of compliance (AMOCs)if they have used the location described in the service information for supplemental type certificate (STC) projects. \n\tWe disagree with the commenter's request to specify alternate relay locations. Figure 15, Sheet 2, of Boeing Special Attention Service Bulletin 757-24-0132, Revision 1, dated June 19, 2012, already provides a note with regard to the relay installation that states, ''if location is used, the new relay can be installed anywhere on the same row.'' We have not changed this final rule in this regard. \n\nRequest To Change Wire Bundle Routing \n\n\n\tUAL requested that the wire bundle routing described in Figure 1, Sheet 2, of Boeing Special Attention Service Bulletin 757-24-0132, Revision 1, dated June 19, 2012, be moved to a location that is easier to access. UAL stated that bundle routing near diamond ''B'' by station 288 can be very difficult because this is behind the P6 panel, which cannot be moved. UAL suggested that following a path in a bundle more forward would beeasier. UAL also stated that removing the G1A galley for access is only feasible in a C-check environment; otherwise the cost is prohibitive. \n\tWe disagree with the commenter's request to change the wire bundle routing. Wire bundle W2078 is an existing wire bundle being changed for this modification. The changes to this wire bundle are done near the P5 and P36 panel. Figure 1, of Boeing Special Attention Service Bulletin 757-24-0132, Revision 1, dated June 19, 2012, is only meant to show that the bundle is routed to both panels and the P6 panel, but it does not require a modification in that area. \n\tFigures 2 through 8 of Boeing Special Attention Service Bulletin 757-24-0132, Revision 1, dated June 19, 2012, show the wiring change. The wire from the P6 panel (W2078-0 150-22) is an existing wire and is only modified near the P5 panel (flag note 8). Furthermore, the G1A galley is only removed if it is necessary. Note 5 of section 3.A., General Information, of Boeing Special AttentionService Bulletin 757- 24-0132, Revision 1, dated June 19, 2012, states that, ''If it is necessary to remove more parts for access, you can remove those parts. If you can get access without removing identified parts, it is not necessary to remove all of the identified parts. Jacking and shoring limitations must be observed.'' Therefore, operators can remove other items if it is easier for them. \n\tFinally, in developing an appropriate compliance time for this AD, we considered not only the safety implications, but the manufacturer's recommendations and the practical aspect of accomplishing the actions within an interval of time that corresponds to typical scheduled maintenance for affected operators. We have determined that a 60-month compliance time will ensure an acceptable level of safety and allow the modifications to be done during scheduled maintenance intervals for most affected operators. Also, the Boeing service information cited in the NPRM (77 FR 75402, December 20, 2012), has been available to operators since June 2012; therefore, operators have had ample time to consider initiating those actions that this final rule requires. We have not changed this final rule in this regard. \n\nStatement of STC Effect on Applicability \n\n\n\tAviation Partners Boeing stated that the installation of winglets per STC ST01920SE (http://rgl.faa.gov/Regulatory--and--Guidance-- Library/rgstc.nsf/0/082838ee177dbf62862576a4005cdfc0/$FILE/ ST01920SE.pdf) or STC ST01518SE (http://rgl.faa.gov/Regulatory--and-- Guidance--Library/rgstc.nsf/0/48e13cdfbbc32cf4862576a4005d308b/$FILE/ ST01518SE.pdf) do not affect the accomplishment of the manufacturer's service instructions. \n\tWe have added new paragraph (c)(3) to this final rule to state that installation of STC ST01920SE or STC ST01518SE does not affect the ability to accomplish the actions required by this final rule. Therefore, for airplanes on which STC ST01920SE or STC ST01518SE is installed, a ''change in product'' AMOC approval request is not necessary to comply with the requirements of 14 CFR 39.17. \n\nConclusion \n\n\n\tWe reviewed the relevant data, considered the comments received, and determined that air safety and the \n\n((Page 72566)) \n\npublic interest require adopting this AD with the change described previously and minor editorial changes. We have determined that these minor changes: \n\tAre consistent with the intent that was proposed in the NPRM (77 FR 75402, December 20, 2012) for correcting the unsafe condition; and \n\tDo not add any additional burden upon the public than was already proposed in the NPRM (77 FR 75402, December 20, 2012). \n\nCosts of Compliance \n\n\n\tWe estimate that this AD affects 1,085 airplanes of U.S. registry. \n\tWe estimate the following costs to comply with this AD: \n\n\n\tEstimated Costs ---------------------------------------------------------------------------------------------------------------- \n\tCost on U.S. \n\tAction Labor cost Parts cost Cost per product operators ---------------------------------------------------------------------------------------------------------------- Install new air/ground relay; 23 work-hours x Up to $733........ Up to $2,688...... Up to $1,811,712. \n\t674 Model 757 airplanes. $85 per hour = \n\t$1,955. Install new air/ground relay; Up to 35 work- Up to $881........ Up to $3,856...... Up to $1,584,816. \n\t411 Model 767 airplanes. hours x $85 per \n\thour = $2,975. ---------------------------------------------------------------------------------------------------------------- \n\nAuthority for This Rulemaking \n\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\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 ''significantrule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), \n\t(3) Will not affect intrastate aviation in Alaska, and \n\t(4) 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\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.