# AD 2013-10-52: Transfer gearbox assemblies (TGBs) - Type: Emergency airworthiness directive - Status: Historical - Products: General Electric GE90-110B1 and GE90-115B - Effective: June 26, 2013 - Published: June 26, 2013, 78 FR 38195–38197 - Issued: May 16, 2013 - Issued as: Final rule; request for comments - Superseded by: [AD 2013-14-51](https://openairdocs.org/ad/2013-14-51), [AD 2013-15-20](https://openairdocs.org/ad/2013-15-20) - Product type: Engine - Amendment: 39-17488 - Docket: FAA-2013-0447 (https://www.regulations.gov/docket/FAA-2013-0447) - Project: 2013-NE-17-AD - Registered aircraft: 143 may be affected, by airframe or engine model (OpenAirDocs) - Official PDF: https://openairdocs.org/files/sha256/a5/ae/a5ae427e4e4a5d0dbb5dcfbe0795a03fdbafa31622981536d73f9a577e0154b0 (from https://www.govinfo.gov/content/pkg/FR-2013-06-26/pdf/2013-15001.pdf) - Federal Register: https://www.federalregister.gov/documents/2013/06/26/2013-15001/airworthiness-directives-general-electric-company-turbofan-engines - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/F273D3CE93E6CBB286257B960047340E.0001 - DRS record last changed: August 7, 2025 - Page: https://openairdocs.org/ad/2013-10-52 ## Summary We are adopting a new airworthiness directive (AD) for all General Electric Company (GE) GE90-110B1 and GE90-115B turbofan engines. This emergency AD was sent previously to all known U.S. owners and operators of these engines. This AD prohibits operation of an airplane with affected transfer gearbox assemblies (TGBs) installed on both engines five days after the effective date of this AD. This AD was prompted by reports of two failures of TGBs which resulted in in-flight shutdowns (IFSDs). We are issuing this AD to prevent additional IFSDs of one or more engines, loss of thrust control, and damage to the airplane. ## The airworthiness directive 1. The authority citation for part 39 continues to read as follows: 2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD): 2013-10-52 General Electric Company: Amendment 39-17488; Docket No. FAA-2013-0447; Directorate Identifier 2013-NE-17-AD. ### (a) Effective Date This airworthiness directive (AD) is effective June 26, 2013 to all persons except those persons to whom it was made immediately effective by Emergency AD 2013-10-52, issued on May 16, 2013, which contained the requirements of this amendment. ### (b) Affected ADs None. ### (c) Applicability General Electric Company (GE) GE90-110B1 and GE90-115B turbofan engines with a transfer gearbox assembly (TGB), part number 2115M33G07 or 2115M33G08, serial number (S/N) listed in Figure 1 to paragraph (c) of this AD, installed. *Figure 1 to Paragraph ( c)—Transfer Gearbox Assembly S/Ns* | | | | | | --- | --- | --- | --- | | FIA0HYRT | FIA0JGE8 | FIA0J3YC | FIA0JRTW | | FIA0HV16 | FIA0JEH2 | FIA0JEH3 | FIA0K4M6 | | FIA0J31V | FIA0JGE7 | FIA0JAVL | FIA0JN33 | | FIA0H0R1 | FIA0JLAV | FIA0J70G | FIA0K7TV | | FIA0J3YE | FIA0JLAY | FIA0HV18 | FIA0K56H | | FIA0J1L0 | FIA0JGFC | FIA0J70E | FIA0K7TY | | FIA0J3YF | FIA0JN31 | FIA0JGE9 | FIA0K7TW | | FIA0J7FF | FIA0JN3Y | FIA0JLAW | FIA0K4M5 | | FIA0J5LR | FIA0JGFF | FIA0H0R3 | FIA0K56G | | FIA0J7FH | FIA0JN30 | FIA0JGE6 | FIA0JN32 | | FIA0J7FC | FIA0J7Y9 | FIA0JT56 | FIAAV6M1 | | FIA0J70A | FIA0JAVM | FIA0JT57 | FIA0K7T1 | | FIA0J7Y8 | FIA0JGFA | FIA0J7FE | FIAAP6C4 | | FIA0J7Y7 | FIA0JLAT | FIA0JT6K | FIA0K7T0 | | FIA0J31W | FIA0JT58 | FIA0JT6L | FIAATMYA | | FIA0J70C | FIA0K2H1 | FIA0JLAR | FIA0K56K | | FIA0JAVH | FIA0HP4Y | FIA0JRT5 | FIAATH0T | | FIA0J7FG | FIA0HV17 | FIA0JRT4 | FIA0K56J | | FIA0J70F | FIA0HV19 | FIA0JT6J | FIAAPA8T | | FIA0JAVK | FIA0HWG3 | FIA0K2H4 | FIAAVTMA | | FIA0JEH4 | FIA0J3YG | FIA0JRTV | FIA0JRTY | | FIA0J5LY | FIA0H0R0 | FIA0K2H2 | FIAAR7C0 | | FIA0J5LT | FIA0HYRV | FIA0K2H3 | FIAARW1V | | FIA0J5LW | FIA0H0R2 | FIA0K4M2 | FIA07PAN | | FIA0JEH5 | FIA0J1LY | FIA0K4M4 | FIA06VPP | | FIA0JAVJ | FIA0J31T | FIA0JT59 | F1A03RR4 | | FIA0JGE5 | FIA0J1LW | FIA0K2H5 | FIA0JGFE | | FIA0JEH6 | FIA0J5LV | FIA0K4M1 | FIA02N6R | | FIA0JGEH | FIA0HYRR | FIA0K56L | | | FIA0J1LV | FIA0J31R | FIA0K4M3 | | ### (d) Unsafe Condition This AD was prompted by reports of two failures of TGBs which resulted in in-flight shutdowns (IFSDs). We are issuing this AD to prevent additional IFSDs of one or more engines, loss of thrust control, and damage to the airplane. ### (e) Compliance (1) Comply with this AD within the compliance time specified, unless already done. (2) Before further flight, do not operate the airplane if more than one installed engine has a TGB S/N listed in Figure 1 to paragraph (c) of this AD. ### (f) Alternative Methods of Compliance (AMOCs) The Manager, Engine Certification Office, FAA, may approve AMOCs for this AD. Use the procedures found in 14 CFR 39.19 to make your request. ### (g) Related Information (1) For further information about this AD, contact: Jason Yang, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7747; fax: 781-238-7199; email: jason.yang@faa.gov. (2) GE GE90-100 Series Alert Service Bulletin (ASB) No. GE90-100 S/B 72-A0558, Revision 1, dated May 14, 2013, and GE90-100 Series ASB No. GE90-100 S/B 72-A0559, dated May 14, 2013, pertain to the subject of this AD. (3) For the service information referenced in this AD, contact: General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, Cincinnati, Ohio 45215; phone: 513-552-3272; email: geae.aoc@ge.com. (4) You may view this service information at the FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA. For information on the availability of this material at the FAA, call 781-238-7125. ## Rule preamble ### Dates This AD is effective June 26, 2013 to all persons except those persons to whom it was made immediately effective by Emergency AD 2013-10-52, issued on May 16, 2013, which contained the requirements of this amendment. We must receive comments on this AD by August 12, 2013. ### Addresses You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods: • Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments. • Fax: 202-493-2251. • Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590. • Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. For service information identified in this AD, contact General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, Cincinnati, Ohio 45215; phone: 513-552-3272; email: geae.aoc@ge.com. ### For further information contact Jason Yang, Aerospace Engineer, Engine Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803; phone: 781-238-7747; fax: 781-238-7199; email: jason.yang@faa.gov. ### Discussion On May 16, 2013, we issued Emergency AD 2013-10-52, which prohibits operation of an airplane with affected TGBs installed on both engines five days after receipt of the emergency AD. The emergency AD was sent previously to all known U.S. owners and operators of these GE90-110B1 and GE90-115B turbofan engines. This action was prompted by reports of two failures of TGBs which resulted in IFSDs. Investigation has revealed that the failures were caused by TGB radial gear cracking and separation. Further inspections found two additional radial gears with cracks. This condition, if not corrected, could result in additional IFSDs of one or more engines, loss of thrust control, and damage to the airplane. ### Relevant Service Information We reviewed GE GE90-100 Series Alert Service Bulletin (ASB) No. GE90-100 S/B 72-A0558, Revision 1, dated May 14, 2013, and GE90-100 Series ASB No. GE90-100 S/B 72-A0559, dated May 14, 2013. The ASBs provide additional information regarding the affected TGBs. ### FAA's Determination We are issuing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design. ### AD Requirements This AD prohibits operation of an airplane with affected TGBs installed on both engines five days after the effective date of this AD. ### Interim Action We consider this AD to be an interim action. We anticipate that further AD action will follow. ### FAA's Determination of the Effective Date An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because of the five-day compliance time. Therefore, we find that notice and opportunity for prior public comment are impracticable and that good cause exists for making this amendment effective in less than 30 days. ### Comments Invited This AD is a final rule that involves requirements affecting flight safety and was not preceded by notice and an opportunity for public comment. However, we invite you to send any written data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number FAA-2013-0447 and Directorate Identifier 2013-NE-17-AD at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of those comments. We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this AD. ### Costs of Compliance We estimate that this AD affects 20 engines installed on airplanes of U.S. registry, and because the compliance is only an airplane operation prohibition, the cost of compliance on U.S. operators is $0. ### Authority for This Rulemaking Title 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. We 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. ### Regulatory Findings This 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. For the reasons discussed above, I certify that this AD: (1) Is not a “significant regulatory action” under Executive Order 12866, (2) Is not a “significant rule” under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), (3) Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction, and (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. ### Adoption of the Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS E00049EN](https://openairdocs.org/tcds/E00049EN): General Electric Company GE Aviation; names 2 of 8 models: GE90-110B1, GE90-115B ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 143 (0 by airframe model, 143 by engine model) - Makers: Boeing 143 Models with the most aircraft: - [GE GE90-110B1](https://openairdocs.org/engine/ge-ge90-110b1): 91 aircraft (engine model) - [GE GE90-115B](https://openairdocs.org/engine/ge-ge90-115b): 51 aircraft (engine model) - [GE GE90 series](https://openairdocs.org/engine/ge-ge90-series): 1 aircraft (engine model) All 3 models: https://openairdocs.org/ad/2013-10-52/models.md Every aircraft: https://openairdocs.org/ad/2013-10-52/aircraft.md ## Related documents - [AD 2013-14-51](https://openairdocs.org/ad/2013-14-51) (historical): Failure of a transfer gearbox assembly radial gearshaft · General Electric GE90-110B1 and GE90-115B. Supersedes this AD - [AD 2013-15-20](https://openairdocs.org/ad/2013-15-20): Transfer gearbox assembly (TGB) radial gearshafts · General Electric GE90-110B1, GE90-113B, GE90-115B and 5 more. Effective Aug 21, 2013. Supersedes this AD No proposed rule in this release led to it. Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.