Discussion \n\n\n\tThe FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, 747- 200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP series airplanes. The NPRM published in the Federal Register on November 8, 2019 (84 FR 60351). The NPRM was prompted by fuel system reviews conducted by the manufacturer indicating that the existing bond path design provides insufficient bond resistance margin between the fuel pump motor/impeller and structure. The NPRM proposed to require replacement of the bonding jumpers on the APU fuel pump. The NPRM also proposed to require, for certain airplanes, installation of a second bonding jumper; an inspection of the override/jettison fuel pumps and transfer/jettison fuel pumps to determine if the bonding jumper has a one-piece braid or two-piece braid and replacement of the bonding jumper if necessary; and replacement of the bonding jumper on the electrical scavenge fuel pump. \n\nComments \n\n\n\tThe FAA gave the public the opportunity to participate in developing this final rule. The following presents the comments received on the NPRM and the FAA's response to each comment. \n\n((Page 20409)) \n\nSupport for the NPRM \n\n\n\tThe Air Line Pilots Association, International (ALPA) and Boeing indicated support for the NPRM. An anonymous commenter also indicated support for the NPRM. Two other commenters, Patrick Imperatrice and Gaganjyot Arora, stated that they supported the NPRM. \n\nRequest To Clarify Requirements for Certain Airplanes \n\n\n\tLufthansa Technik AG on behalf of Lufthansa German Airlines requested that the FAA add a note to the proposed AD to clarify the requirements for airplanes on which BMS 10-20 was not used while accomplishing Boeing Service Bulletin 747-28-2228, dated November 4, 1999 (Boeing Service Bulletin 747-28-2228, Revision 1, datedSeptember 27, 2001, is referred to as the appropriate source of service information for accomplishing the proposed actions.). Lufthansa Technik AG asked that the FAA consider whether an airplane on which Boeing Service Bulletin 747-28-2228, dated November 4, 1999, was accomplished without using BMS 10-20 is in compliance with the proposed AD. \n\tThe FAA agrees to clarify the requirements. Boeing Service Bulletin 747-28-2228, Revision 1, dated September 27, 2001, specifies it is necessary to rebond the bonding jumper if BMS 10-20 was applied on the mating surfaces between the bonding jumper and rear spar while accomplishing Boeing Service Bulletin 747-28-2228, dated November 4, 1999. However, Boeing Service Bulletin 747-28-2228, dated November 4, 1999, specifies limits to the bonding resistance values between the pump housing and rear spar structure. Complying with those bonding resistance values is required to address the unsafe condition, regardless of whether or not BMS 10-20 was applied. These bonding resistance limits were unchanged between Boeing Service Bulletin 747- 28-2228, dated November 4, 1999, and Boeing Service Bulletin 747-28- 2228, Revision 1, dated September 27, 2001. Therefore, credit can be given if it can be conclusively determined that all bonding resistance limits specified in Boeing Service Bulletin 747-28-2228, Revision 1, dated September 27, 2001, have been met. The FAA has added paragraph (i) to this AD to provide this credit and reidentified subsequent paragraphs accordingly. \n\nConclusion \n\n\n\tThe FAA reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this final rule with the changes described previously and minor editorial changes. The FAA has determined that these minor changes: \n\tAre consistent with the intent that was proposed in the NPRM for addressing the unsafe condition; and \n\tDo not add any additional burden upon the public than was already proposed in the NPRM. \n\tThe FAA also determined that these changes will not increase the economic burden on any operator or increase the scope of this final rule. \n\nRelated Service Information Under 1 CFR Part 51 \n\n\n\tThe FAA reviewed Boeing Service Bulletin 747-28-2228, Revision 1, dated September 27, 2001. This service information describes procedures for a replacement of the bonding jumpers on the APU fuel pump; an inspection of the six override/jettison fuel pumps and of the two transfer/jettison fuel pumps to determine if the bonding jumper has a one-piece braid or two-piece braid, and replacement of the existing bonding jumper if the bonding jumper has a one-piece braid; installation of a second bonding jumper; and replacement of the bonding jumper on the electrical scavenge fuel pump. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.Other Relevant Rulemaking \n\n\n\tBoeing Service Bulletin 747-28-2228, Revision 1, dated September 27, 2001, identifies ''Boeing Service Bulletin 747-28-2033'' as a concurrent requirement for certain airplanes. Boeing Alert Service Bulletin 747-28A2033, Revision 1, dated December 18, 2003, is the appropriate source of service information for accomplishing the installation required by AD 2005-01-07, Amendment 39-13931 (70 FR 1336, January 7, 2005) (''AD 2005-01-07''). The compliance time for accomplishing the installation required by AD 2005-01-07 has already passed; therefore, it is not necessary to include Boeing Alert Service Bulletin 747-28A2033 as a concurrent requirement in this AD. The FAA issued AD 2005-01-07 to ensure adequate electrical bonding between the housing of each fuel pump and airplane structure outside the fuel tanks. Inadequate electrical bonding, in the event of a lightning strike or fuel pump electrical fault, could cause electrical arcing and ignition of fuel vapor in the wing fuel tank, which could result in a fuel tank explosion. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects 74 airplanes of U.S. registry. The FAA estimates 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 ---------------------------------------------------------------------------------------------------------------- Replacement, Installation, and Up to 15 work- Up to $2,000...... Up to $3,275...... Up to $242,350. \n\tInspection. hours x $85 per \n\thour = Up to \n\t$1,275. ---------------------------------------------------------------------------------------------------------------- \n\n\n\tThe FAA estimates the following costs to do any necessary replacements that would be requiredbased on the results of the proposed inspection. The FAA has no way of determining the number of aircraft that might need these replacements: \n\n\n\tOn-Condition Costs ---------------------------------------------------------------------------------------------------------------- \n\tAction Labor cost Parts cost Cost per product ---------------------------------------------------------------------------------------------------------------- Replacement.......................... Up to 6 work-hours x Up to $950............. Up to $1,460. \n\t$85 per hour = Up to \n\t$510. ---------------------------------------------------------------------------------------------------------------- \n\n\n\n((Page 20410)) \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\tThe FAA is 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) Will not affect intrastate aviation in Alaska, 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\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.