Background \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 all GE GEnx-1B64, - 1B64/P1, -1B64/P2, -1B67, -1B67/P1, -1B67P2, -1B70, -1B70/75/P1, -1B70/ 75/P2, -1B70/P1, -1B70/P2, -1B70C/P1, -1B70C/P2, -1B74/75/P1, -1B74/75/ P2, -1B76/P2, and -1B76A/P2 model turbofan engines. The NPRM published in the Federal Register on May 6, 2020 (85 FR 26891). The NPRM was prompted by reports of combustor case burn-through. The NPRM proposed to require installation of EEC software, version B205 or later. The FAA is issuing this AD to address the unsafe condition on these products. \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\nRequest To Supersede Existing AD \n\n\n\tAmerican Airlines (AAL) suggested that the FAA change this AD to supersede docket number FAA-2019-0683, project identifier 2015-NE-02-AD (84 FR 63820, November 19, 2019) (''NPRM 2015-NE-02-AD''). NPRM 2015- NE-02-AD proposed removing EEC software version B195 and earlier from GEnx-1B engines, along with an equivalent EEC software for GEnx-2B engines to improve safeguards against ice crystal icing. EEC software version B205 incorporates all required changes that satisfy the intent of NPRM 2015-NE-02. \n\tThe FAA disagrees. The unsafe condition addressed by this AD was prompted by reports of combustor case burn-through. In contrast, the final rule to NPRM 2015-NE-02-AD, AD 2020-13-04, Amendment 39-21149 (85 FR 37000, June 19, 2020) (''AD 2020-13-04'') was prompted by power loss in ice crystal icing conditions. Although the ice crystal icing required actions of AD 2020-13-04 are achieved through the update to EEC software version B205, the unsafe conditions that prompted each AD are different, and the corrective actions are independent. Further, AD 2020-13-04 affects more GEnx model turbofan engines than this AD. \n\n((Page 61812)) \n\nRequest To Add Terminating Action \n\n\n\tAAL requested the FAA add that compliance with this AD is a terminating action to paragraphs (g) and (i) of AD 2013-24-01, Amendment 39-17675 (78 FR 70851, November 27, 2013) (''AD 2013-24- 01''), similar to the terminating action in AD 2017-09-06, Amendment 39-18868 (82 FR 21111, May 5, 2017) (''2017-09-06''). AAL noted that NPRM 2015-NE-02-AD (AD 2020-13-04) indicated that it would supersede AD 2017-09-06, but did not provide a terminating action to paragraphs (g) and (i) of AD 2013-24-01, as was done in AD 2017-09-06. AAL commented that EEC software version B205 incorporated the software changes to address the unsafe ice crystal icing condition so compliance with paragraphs (g) and (i) of AD 2013-24-01 should no longer be required. \n\tThe FAA disagrees. As indicated in a comment response to NPRM 2015- NE-02-AD, the FAA disagreed with adding a terminating action in AD 2020-13-04 because the FAA's approval of alternative methods of compliance to AD 2013-24-01 made a terminating action unnecessary in AD-2020-13-04. In this AD, the FAA finds that adding a terminating action is not justified as this AD does not address the unsafe ice crystal icing condition of AD 2020-13-04, AD 2017-09-06, and AD 2013- 24-01. Therefore, no change to this AD is needed. \n\nRequest To Add Boeing Service Information \n\n\n\tQantas Airways Limited (Qantas) commented that GE GEnx-1B Service Bulletin (SB) 73-0085 R00, dated December 23, 2019, describes procedures for installing the EEC software version B205. Qantas further noted that procedures for on-wing installation of EEC software version B205 is described in Boeing B787-81205 SB-730057-00, Issue 001, dated December 23, 2019; Boeing B787-81205 SB-730057-00, Issue 002, dated February 28, 2020; or later FAA approved revisions. The FAA interprets Qantas' comment as a request to add Boeing B787-81205 SB-730057-00, Issue 001, dated December 23, 2019, and Issue 002, dated February 28, 2020; and later FAA approved revisions, to the Related Service Information section of this AD. \n\tThe FAA disagrees with adding the Boeing service information to this AD as Related Service Information as that service information is not necessary to satisfy the requirements of this AD. This AD requires the installation of the EEC software version B205 or later without imposing an installation method. The EEC software can be installed either at the engine-level or on-wing at the aircraft-level using FAA- approved procedures. \n\nRequest To Clarify Applicability \n\n\n\tUnited Airlines (UAL) requested the FAA to clarify if EEC software version B205 or later must be installed on spare EECs or only on engines installed on aircraft, prior to operation. \n\tAn operator of a product that does not meet the requirements of an applicable airworthiness directive is in violation of 14 CFR 39.7. The intent of this AD is to prevent operation of any affected engine installed on an aircraft with EEC software, version B200 or earlier. The requirements of this AD do not apply to spare engines and spare EECs, as they cannot be operated unless installed on an aircraft. No change to this AD is needed. \n\nSupport for the AD \n\n\n\tThe Boeing Company and the Air Line Pilots Association, International, expressed support for the AD as written. AAL supports the intent of the AD. \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 as proposed except for 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\nRelated Service Information \n\n\n\tThe FAA reviewed GE GEnx-1B SB 73-0085 R00, dated December23, 2019. The SB describes procedures for installing the EEC software version B205. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects 176 engines installed on airplanes of U.S. registry. \n\tThe FAA estimates the following costs to comply with this AD: \n\n\n\tEstimated Costs ---------------------------------------------------------------------------------------------------------------- \n\tCost per Cost on U.S. \n\tAction Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Install EEC software version B205 or 1 work-hour x $85 per $0 $85 $14,960 \n\tlater. hour = $85. ---------------------------------------------------------------------------------------------------------------- \n\nAuthority for This Rulemaking \n\n\n\tTitle 49 of the United StatesCode 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 betweenthe 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. \n\n((Page 61813))