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 January 16, 2013 (78 FR 3365). The NPRM proposed to require replacing the pivot link assembly on certain seats, and modifying or replacing the seat track link assemblies on certain seats. Also, for certain airplanes, the NPRM proposed to require installing a new seat track link assembly. \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 (78 FR 3365, January 16, 2013) and the FAA's response to each comment. \n\nRequest To Incorporate Revised Service Information \n\n\n\tBoeing concurred with the content of the NPRM (78 FR 3365, January 16, 2013), but requested that we incorporate Boeing Special Attention Service Bulletin 737-53-1260, Revision 1, dated May 23, 2013, in the AD. Boeing stated that due to manufacturing differences, \n\n((Page 72559)) \n\nsome operators were unable to modify or replace the seat track link assembly using Boeing Special Attention Service Bulletin 737-53-1260, dated May 7, 2007. Boeing also requested that we allow credit for actions done in accordance with Boeing Special Attention Service Bulletin 737-53-1260, dated May 7, 2007. \n\tWe agree to incorporate Boeing Special Attention Service Bulletin 737-53-1260, Revision 1, dated May 23, 2013, in this final rule, which gives an option for operators to modify the seat track link assembly. References have been revised in paragraphs (c)(1), (g)(2), (g)(3), and (i) of this final rule accordingly. (Paragraph (i) of this final rule was referred to as paragraph (h) in the NPRM (78 FR 3365, January 16, 2013).) A new paragraph (h) has been added to this final rule to include the optional modification. We also have added paragraph (j)(2) to this final rule to provide credit for certain actions performed before the effective date of this final rule using Boeing Special Attention Service Bulletin 737-53-1260, dated May 7, 2007. \n\tIn addition, Boeing Special Attention Service Bulletin 737-53-1260, Revision 1, dated May 23, 2013, includes new Group 6 (i.e., certain airplanes previously in Group 1 and Group 5, as identified in Boeing Special Attention Service Bulletin 737-53-1260, dated May 7, 2007). For airplanes in Group 6, we added paragraph (g)(3) to this final rule to provide instructions to contact the FAA for inspection, change, and repair of the seat track link assembly because we have determined that there are unique aspects of these airplanes that require specific instructions for correcting the unsafe condition. Also, paragraph (g)(2) of this final rule has been revised to clarify the applicable groups. New paragraph (g)(4) has been added to this final rule to clarify the requirements for airplanes in Group 5. Subsequent paragraph identifiers have been revised accordingly. \n\nRequest for Credit for Certain Actions \n\n\n\tDelta, Alaska Airlines, WestJet, and Saudi Aramco requested that we provide credit for actions performed prior to the effective date of the AD using Boeing Service Bulletin 737-53-1244, dated April 17, 2003; Revision 1, dated May 29, 2003; Revision 2, dated March 15, 2007; and Revision 3, dated December 4, 2008. The commenters stated that Boeing Service Bulletin 737-53-1244, Revision 5, dated July 27, 2011, specifies that no more work is necessary on airplanes changed in accordance with Boeing Service Bulletin 737-53-1244, dated April 17, 2003; Revision 1, dated May 29, 2003; Revision 2, dated March 15, 2007; and Revision 3, dated December 4, 2008. \n\tWe agree to provide credit for actions performed prior to the effective date of the final rule using Boeing Service Bulletin 737-53- 1244, dated April 17, 2003; Revision 1, dated May 29, 2003; Revision 2, dated March 15, 2007; and Revision 3, dated December 4, 2008. Wehave added a new paragraph (j)(1) to this final rule accordingly. Subsequent paragraph identifiers have been revised accordingly. \n\nRequest To Correct Compliance Table 1 of Boeing Service Bulletin 737- 53-1244, Revision 5, Dated July 27, 2011 \n\n\n\tAlaska Airlines requested that we correct Table 1 of paragraph 1.E., ''Compliance,'' of Boeing Service Bulletin 737-53-1244, Revision 5, dated July 27, 2011, which refers to Boeing Service Bulletin 737-53- 1244, dated April 17, 2003; and Revision 4, dated April 6, 2011 (which was withdrawn by Boeing). \n\tWe partially agree with the request. We agree that the ''Optional Actions'' column of Table 1 of paragraph 1.E., ''Compliance,'' of Boeing Service Bulletin 737-53-1244, Revision 5, dated July 27, 2011, refers to Boeing Service Bulletin 737-53-1244, dated April 17, 2003; and Revision 4, dated April 6, 2011. However, this final rule does not require that action. This final rule requires, among other actions, installation of the new, improved pivot link within 60 months after the effective date of this AD, which is identified in the ''Follow On Actions'' column of Table 1 of paragraph 1.E., ''Compliance,'' of Boeing Service Bulletin 737-53-1244, Revision 5, dated July 27, 2011. No change has been made to this final rule in this regard. \n\nRequest for Clarification of Damage Tolerance Inspections Statement \n\n\n\tAlaska Airlines requested that we clarify the NPRM (78 FR 3365, January 16, 2013) by adding a statement regarding the damage tolerance inspections. Alaska Airlines stated that Boeing Service Bulletin 737- 53-1244, Revision 5, dated July 27, 2012, includes a damage tolerance inspection statement; however, Boeing Special Attention Service Bulletin 737-53-1260, dated May 7, 2007, does not include the statement. The commenter requested that we add a statement to the NPRM indicating that no damage tolerance inspections are required as a result of rework using either service bulletin. \n\tWe agree that the damage tolerance inspection statement was not included in Boeing Special Attention Service Bulletin 737-53-1260, dated May 7, 2007; however, the statement is included in Boeing Special Attention Service Bulletin 737-53-1260, Revision 1, dated May 23, 2013, which is cited in this final rule. No change has been made to this final rule in this regard. \n\nConclusion \n\n\n\tWe reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD with the changes described previously and minor editorial changes. We have determined that these minor changes: \n\t(Agr)re consistent with the intent that was proposed in the NPRM (78 FR 3365, January 16, 2013) for correcting the unsafe condition; and \n\tDo not add any additional burden upon the public than was already proposed in the NPRM (78 FR 3365, January 16, 2013). \n\tWe also determined that these changes will not increase the economic burden on any operator or increase the scope of this AD. \n\nCosts of Compliance \n\n\n\tWe estimate that this AD affects 1,281 airplanes of U.S. registry. \n\tWe estimate the following costs to comply with this AD: \n\n\n\tEstimated Costs -------------------------------------------------------------------------------------------------------------------------------------------------------- \n\tU.S. \n\tAction Labor cost Parts cost Cost per product Airplanes Cost on U.S. operators -------------------------------------------------------------------------------------------------------------------------------------------------------- Replacement or modification........ Up to 41 work-hours x Up to $15,478........ Up to $18,963........ 1,281 Up to $24,291,603. \n\t$85 per hour = $3,485. Concurrent installation or Up to 60 work-hours x Up to $18,089........ Up to $23,189........ 214 Up to $4,962,446. \n\tmodification (Groups 1, 2, 4, and $85 per hour = $5,100. \n\t5 airplanes). -------------------------------------------------------------------------------------------------------------------------------------------------------- \n\n\n\n((Page 72560)) \n\n\n\tWe have received no definitive data that would enable us to provide a cost estimate for the actions required for airplanes in Group 6 identified in Boeing Special Attention Service Bulletin 737-53-1260, Revision 1, dated May 23, 2013. \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 commerceby 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 ''significant rule'' 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.