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 737-300, -400, -500, -600, -700, -700C, -800, and -900 series airplanes. That NPRM was published in the Federal Register on November 7, 2007 (72 FR 62802). That NPRM proposed to require installing a new circuit breaker, relays, and wiring to allow the flightcrew to turn off electrical power to the in-flight entertainment (IFE) systems and other non-essential electrical systems through a switch in the flight compartment, and doing other specified actions. \n\nComments \n\n\tWe gave the public the opportunity to participate in developing this AD. We considered the comments received from the six commenters. \n\nRequest To Exclude Certain Airplanes From the Applicability \n\n\tMr. Ian S. Murton requests that we revise paragraph (c)(2) of the applicability of the NPRM to exclude Model 737-700series airplanes having variable numbers (V/Ns) YB101 through YB114 inclusive. These airplanes are listed in the effectivity of Boeing Service Bulletin 737- 24-1147, Revision 1, dated March 1, 2007, which is referenced in paragraph (c)(2) of the NPRM. As justification, the commenter states that the operator of these airplanes has owned the airplanes since delivery from Boeing, and that IFE systems are not installed on these airplanes. The commenter also states that the operator took possession of the airplane having V/N YB114 18 months after Boeing issued the original issue of Boeing Service Bulletin 737-24-1147, dated November 20, 2003, and that the operator decided not to accomplish the actions specified in that service bulletin. The commenter would like to know how the proposed requirements of the NPRM would affect this range of airplanes. The commenter also states that perhaps the applicability of the NPRM should be amended to include only airplanes that have the IFE systems installed. \n\tWe disagree with revising the applicability of this AD because we have determined that the unsafe condition exists on the airplanes identified in the Boeing service bulletins that are referenced in paragraph (c) of this AD. The effectivities of those service bulletins are based upon the delivered configuration of the airplanes. Boeing has confirmed that it installed IFE systems on airplanes having V/Ns YB101 through YB114 inclusive. If the IFE systems were either removed after delivery, or have never been installed contrary to the effectivity of Boeing Service Bulletin 737-24-1147, Revision 1, dated March 1, 2007, then under the provisions of paragraph (k) of this AD, we will consider requests for approval of an alternative method of compliance (AMOC) if sufficient data are submitted to substantiate that the design change is not necessary. We have not changed the AD in this regard. \n\nRequest To Exclude Certain Boeing Business Jets From the Applicability \n\n\tBoeing ExecutiveFlight Operations requests that we revise paragraph (c) of the applicability of the NPRM to exclude certain Boeing business jets (BBJs) equipped with a passenger entertainment switch (PES), certified under a Supplemental Type Certificate (STC). If these airplanes are not excluded from the applicability, then the commenter requests that the FAA provide additional detail on what specific interior systems or equipment need to have a means of disconnection, so that operators can accurately petition and apply for an AMOC. The commenter states that Boeing delivered these airplanes without an interior to a customized completion center, where they were modified to a custom interior specification and design that are certified by an STC. \n\tAccording to the commenter, many of the BBJ interior installations incorporate either a PES, or load shed switching, that will remove power from the interior equipment and systems, as required by sections 25.1309, 25.1351, 25.1353, and 25.1355 of the FederalAviation Regulations (14 CFR 25.1309, 14 CFR 25.1351, 14 CFR 25.1353, and 14 CFR 25.1355). The commenter also states that Boeing Service Bulletin 737- 24-1147, Revision 1, dated March 1, 2007, does not consider the BBJ and BBJ2 configurations separate from commercial airline interior configurations and does not provide enough details as to what systems or equipment need to be isolated with the PES disconnects. \n\tWe disagree with revising the applicability of this AD because we have determined that the unsafe condition exists on the airplanes identified in the Boeing service bulletins that are referenced in paragraph (c) of this AD. The effectivities of those service bulletins are based upon the delivered configuration of the airplanes. \n\tThe "load shed switching'' function is for an overload condition during normal operation where power will be removed from non-essential systems, such as galley, IFE systems, etc. This AD, however, has a different purpose, which is to independently remove power from the IFE systems and other non-essential equipment in case of emergency, according to FAA Policy Memorandum PS-ANM100-2000-00105, "Interim Policy Guidance for Certification of In-Flight Entertainment Systems on Title 14 CFR Part 25 Aircraft,'' dated September 18, 2000. Policy Memorandum PS-ANM100-2000-00105 specifies that there should be a manual main shutoff switch within reach of flight or cabin crews to be used in case of emergency to shut off all non-essential power. FAA Policy Memorandum ANM-01-111-165, "Policy Statement on Certification of Power Supply Systems for Portable Electronic Devices (PES) on Part 25 Airplanes,'' dated March 18, 2005, covers the PES power removal switch as well. \n\tUnder the provisions of paragraph (k) of this AD, we will consider requests for approval of an AMOC if sufficient data are submitted to substantiate that an alternate design change would provide an acceptable level of safety. We have not changed the AD in this regard. \n\nRequests To Allow Certain Service Bulletins as AMOCs \n\n\tAircraft Maintenance Engineering Services SARL requests that we consider the following service information as AMOCs to the proposed requirements of the NPRM: \n\tLufthansa Technik Engineering Bulletin 737-EB24-0073, Revision 01, for addressing the unsafe condition on the Model 737-700 series airplane having serial number (S/N) 29972. \n\tLufthansa Technik Engineering Bulletin 737-EB24-0088, Revision 01, for addressing the unsafe condition on the Model 737-800 series airplane having S/N 32438. \n\tRaytheon Service Bulletin 737IGW-24-1, dated August 11, 2000, for addressing the unsafe condition on the Model 737-700 series airplane having S/N 28976. \n\tThe commenter states that these bulletins address the intent of Boeing Service Bulletin 737-24-1147, Revision 1, dated March 1, 2007. The Lufthansa Technik engineering bulletins provide procedures for installing a cut-off switch in the P5 panel to interrupt electrical power to the IFE system.The Raytheon service bulletin provides procedures for installing a flight compartment switch for removing power from the IFE systems and other non-essential systems. The procedures in the Raytheon service bulletin were accomplished in accordance with STC ST09106AC-D, issued July 6, 2000. \n\tWe disagree because an AMOC can be granted only after an AD has been issued. In addition, we have not included the Lufthansa and Raytheon service bulletins as a method of compliance within this AD; we do not consider it appropriate to include various provisions in an AD applicable only to individual airplane serial numbers or to a single operator's unique use of an affected airplane. Once we issue this AD, the commenter may request approval of an AMOC under the provisions of paragraph (k) of this AD. Sufficient data must be submitted to substantiate that the design change would provide an acceptable level of safety. We have not changed the AD in this regard. \n\nRequest To Revise Paragraph (f) of the NPRM \n\n\tBoeing requests that we delete the last sentence of paragraph (f) of the NPRM, which states: "Concurrently Modify P5-13 Module Assembly on Model 737-300 Series Airplanes.'' Boeing states that the sentence is redundant and confusing because the concurrent requirements are addressed by paragraph (h) of the NPRM, and that those requirements only apply to a certain group of airplanes. \n\tWe disagree because the phrase that the commenter refers to is not a sentence in paragraph (f) of the NPRM. That phrase is the heading for paragraph (g) of the NPRM, which gives the concurrent requirements. No change to the AD is necessary in this regard. \n\nRequest To Extend the Compliance Time \n\n\tThe Air Transport Association, on behalf of its member American Airlines, requests that we extend the compliance time from 60 to 72 months. American Airlines states that it is requesting this extension to align the compliance time with its heavy maintenance program and to avoid an unnecessary financial burden. American Airlines states that incorporating the modification requires extensive "power off A/C time,'' and that this can be accommodated only at a heavy C check, which is scheduled by most in the industry at 72-month intervals. American Airlines also states that the proposed 60-month compliance time will have a substantial impact by requiring the unscheduled removal of its airplanes from service. American Airlines estimates that 14 of its affected airplanes will require special scheduling and out- of-service time, which equates to about 42 days for an additional cost impact of $600,000. \n\tWe disagree with extending the compliance time. In developing an appropriate compliance time for this action, we considered the safety implications, parts availability, and normal maintenance schedules for the timely accomplishment of the modification. In consideration of these items, we have determined that a 60-month compliance time will ensure an acceptable level of safety. However,according to the provisions of paragraph (k) of this AD, we might approve requests to adjust the compliance time if the request includes data that prove that \nthe new compliance time would provide an acceptable level of safety. We have not changed the AD in this regard. \n\nChange Made to Paragraph (i) of This AD \n\n\tWe have revised paragraph (i) of this AD to specify that the requirements of that paragraph apply to "* * * Groups 3 through 139. * * *'' In the NPRM, we inadvertently specified that the proposed requirements would apply to Groups 1 through 139. This change agrees with paragraph 1.B. of Boeing Service Bulletin 737-24-1147, Revision 1, dated March 1, 2007. \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 theAD. \n\nCosts of Compliance \n\n\tThere are about 1,617 airplanes of the affected design in the worldwide fleet. The following table provides the estimated costs, at an average labor rate of $80 per hour, for U.S. operators to comply with this AD. \n\n\tEstimated Costs\n\n\nModel\nAction\nWork hours\nParts\nCost per airplane\nNumber of U.S.-registered airplanes\nFleet cost\n737-300, -400, and -500 series airplanes\nInstallation of circuit breaker, relays, and wiring\nUp to 31\nUp to $2,925\n$5,405\n1\n$5,405\n737-300 series airplanes\nConcurrent modification of P5-13 module assembly\n1\n$2,327\n$2,407\n1\n$2,407\n\nInstallation of circuit breaker, relays, and wiring\nUp to 52\nUp to $10,968\n$15,128\n586\n$8,865,008\n737-600, -700, -700C, -800, and -900 series airplanes\nConcurrent modification of P5-13 module assembly\n4\n$9,241\n$9,561\n586\n$5,602,746\n737-800 series airplanes\nInstallation of wiring for the No. 4 VDU\n12\n$3,372\n$4,332\n2\n$8,664\n\nAuthority for This RulemakingTitle 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 DIRECTIVES1. 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: