Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes, 47337-47341 [2022-16535]

Download as PDF Federal Register / Vol. 87, No. 148 / Wednesday, August 3, 2022 / Rules and Regulations DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2021–0958; Project Identifier 2019–CE–010–AD; Amendment 39–22133; AD 2022–16–04] RIN 2120–AA64 Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Final rule. AGENCY: The FAA is adopting a new airworthiness directive (AD) for all Gulfstream Aerospace Corporation (Gulfstream) Model GV and GV–SP airplanes. This AD was prompted by corrosion of the horizontal stabilizer lower bonded skin assemblies. This AD requires inspecting the horizontal stabilizer lower skin and associated bonded doublers and bonded stringers, repairing any area with corrosion beyond allowable damage limits, and incorporating revisions to the airworthiness limitations section (ALS) in the existing aircraft maintenance manual (AMM) or progressive maintenance program. The FAA is issuing this AD to address the unsafe condition on these products. DATES: This AD is effective September 7, 2022. The Director of the Federal Register approved the incorporation by reference of certain publications listed in this AD as of September 7, 2022. ADDRESSES: For service information identified in this final rule, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402; phone: (800) 810–4853; fax: (912) 965–3520; email: pubs@gulfstream.com; website: www.gulfstream.com/en/customersupport/. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call (817) 222–5110. It is also available at www.regulations.gov by searching for and locating Docket No. FAA–2021– 0958. lotter on DSK11XQN23PROD with RULES1 SUMMARY: Examining the AD Docket You may examine the AD docket at www.regulations.gov by searching for and locating Docket No. FAA–2021– 0958; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. VerDate Sep<11>2014 17:44 Aug 02, 2022 Jkt 256001 The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M– 30, West Building Ground Floor, Room W12–140, 1200 New Jersey Avenue SE, Washington, DC 20590. FOR FURTHER INFORMATION CONTACT: Ronald Wissing, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: (404) 474–5552; email: 9-ASO-ATLACO-ADs@faa.gov. SUPPLEMENTARY INFORMATION: Background The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all Gulfstream Model GV and GV–SP airplanes. The NPRM published in the Federal Register on November 5, 2021 (86 FR 61088). The NPRM was prompted by bond line corrosion on Model GV and GV–SP airplanes, which causes disbonding between the horizontal stabilizer lower skin and associated bonded doublers and bonded stringers. Gulfstream determined that the existing visual inspection in the AMM did not reliably detect bond line corrosion and added a repetitive nondestructive testing (NDT) inspection to detect the damage. In the NPRM, the FAA proposed to require inspecting the horizontal stabilizer lower skin and associated bonded doublers and bonded stringers, repairing any area with corrosion beyond allowable damage limits, and incorporating revisions to the ALS in the existing AMM. The FAA is issuing this AD to address the unsafe condition on these products. Discussion of Final Airworthiness Directive Comments The FAA received comments from one commenter, Gulfstream. The following presents the comments received on the NPRM and the FAA’s response to each comment. Request To Clarify Information in the Preamble Gulfstream requested that the FAA revise a phrase describing part of the proposed corrective action under SUMMARY and under the ‘‘Proposed AD Requirements in This NPRM’’ section of SUPPLEMENTARY INFORMATION. Gulfstream requested the FAA change ‘‘repairing the area susceptible to corrosion’’ to ‘‘identify if a repair is required.’’ Gulfstream stated that the bonded structure is ‘‘susceptible’’ to corrosion but does not necessarily PO 00000 Frm 00007 Fmt 4700 Sfmt 4700 47337 require ‘‘repair’’ because the need for repair is based on the inspection results. The FAA agrees that all areas susceptible to corrosion do not necessarily require repair. The FAA has revised the SUMMARY of this final rule to clarify that only areas with corrosion that exceeds allowable damage limits need to be repaired. The ‘‘Proposed AD Requirements in This NPRM’’ section is not restated in this final rule, so a change is unnecessary. Request To Revise the Description of a Service Document Gulfstream requested the FAA change the description of Gulfstream Service Letter Document No. GSL505510019, Revision E, dated September 3, 2021, in the ‘‘Other Related Service Information’’ section of the preamble. In the NPRM, the FAA stated that the service letter contains procedures for applying onwing corrosion inhibiting compound (CIC) to the horizontal stabilizer. Gulfstream advised that this description is inaccurate because although the service letter specifies applying CIC, it references another service letter for the application instructions. Gulfstream requested that the preamble state instead that this service letter ‘‘contains allowable damage limits for the horizontal stabilizer assembly.’’ The FAA agrees and has revised this final rule accordingly. Request Regarding the Airplane Effectivity Range Gulfstream requested that the FAA remove language in the preamble explaining that the proposed AD would apply to all Model GV and GV–SP airplanes, while the service bulletins exclude certain serial-numbered airplanes. Gulfstream also requested that the inspection proposed in paragraph (i) of the proposed AD not be required for these same serial-numbered airplanes. Gulfstream stated that four airplanes were excluded from the effectivity of the customer bulletin because the airplanes had not yet reached the baseline compliance time for doing the initial ‘‘Part II’’ inspection of the horizontal stabilizer lower skin. Gulfstream explained that removing those four airplanes from the inspection portion of the proposed AD would not have an impact on safety, because those airplanes will be inspected in accordance with the 144-month entry into service inspection specified in Chapter 5 of the AMM. The FAA disagrees. Gulfstream’s request appears to be based on the compliance time for those four airplanes and not whether they are subject to the unsafe condition identified in this AD. E:\PICKUP\03AUR1.SGM 03AUR1 47338 Federal Register / Vol. 87, No. 148 / Wednesday, August 3, 2022 / Rules and Regulations The inspection required by paragraph (i) of this AD is necessary to correct the unsafe condition on all Model GV–SP airplanes with a serial number in the range of 5001 through 5158. The FAA did not change this AD based on this comment. Request To Include Terminating Action Gulfstream requested that the FAA add terminating actions for the ALS revision proposed in paragraph (g) and for the inspection proposed in paragraph (i) of the proposed AD. Gulfstream stated that otherwise owners will have to comply for an indefinite period. The FAA does not agree because paragraphs (g) and (i) of this AD require one-time actions and not repetitive actions; therefore, terminating action is not necessary. Once an operator has revised the maintenance or inspection program for its airplane by incorporating the applicable ALS revision, the operator has complied with paragraph (g) of this AD. As explained in the NPRM, although the service bulletins allow the inspection to be repeated indefinitely every 48 months, this AD does not. Instead, paragraph (i) of this AD requires the inspection once, and any necessary repairs within 48 months after the inspection. The FAA did not change this AD based on this comment. lotter on DSK11XQN23PROD with RULES1 Request To Remove Entry Into Service Criteria Gulfstream requested that the FAA revise paragraph (i) of the proposed AD to remove the criteria that the inspection be required for airplanes ‘‘where more than 132 months have elapsed since the original certificate of airworthiness issue date (often referred to as entry into service date).’’ In support, Gulfstream explained that this language is no longer applicable because all affected airplanes have accumulated 132 months since entry into service. In addition, Gulfstream noted that the entry into service date and the original certificate of airworthiness issue date are two different dates and are not interchangeable. The FAA agrees and has revised paragraph (i) of this AD accordingly. Request To Remove Note Regarding ALS Inspections Gulfstream requested that the FAA remove Note 2 to the introductory text of paragraph (i) of the proposed AD, which advised that the inspections listed in the ALS revision (required by paragraph (g) of the proposed AD) must be done at the same time as the Part II inspection. Gulfstream stated it is not VerDate Sep<11>2014 17:44 Aug 02, 2022 Jkt 256001 necessary to mandate the ALS maintenance inspections at the same time as the Part II inspection of the horizontal stabilizer lower skin for bond line corrosion. Gulfstream explained there is no reason to accomplish these actions together and doing so could result in duplication of efforts. The FAA agrees that, to correct the unsafe condition, the ALS maintenance inspections are not required at the same time as the airworthiness inspection of the horizontal stabilizer lower skin for bond line corrosion. However, operators may align these inspections to establish a baseline for the required repetitive inspection intervals. The FAA has revised Note 2 to the introductory text of paragraph (i) of this AD accordingly. Request To Clarify Note 2 of the Proposed AD Gulfstream requested the FAA clarify the intent and placement of Note 2, which was located after the introductory text of paragraph (i) of the proposed AD and before paragraphs (i)(1) and (2) of the proposed AD. Gulfstream explained that due to the placement of the note, it is unclear whether paragraphs (i)(1) and (2) of the proposed AD are part of the note or whether they are lower level paragraphs of paragraph (i) of the proposed AD. Gulfstream also stated that this note does not follow FAA policy and guidance, which states that notes are for informational purposes, because it introduces a requirement not otherwise stated in the AD. Paragraphs (i)(1) and (2) of this AD are lower level paragraphs of paragraph (i) of this AD. Paragraph (i) of this AD requires inspecting the horizontal stabilizer lower skin for bond line corrosion and applying CIC. Paragraphs (i)(1) and (2) of this AD provide the compliance time for repairing any corrosion found as a result of the inspection: either within 48 months after applying CIC if the corrosion is within allowable damage limits, or before further flight if any corrosion exceeds allowable damage limits. The placement of the note after the introductory text of paragraph (i) of this AD follows the formatting requirements for regulatory documents in the Office of the Federal Register’s Document Drafting Handbook. The FAA did not change this AD based on this comment. Request To Remove Paragraphs (i)(1) and (2) of the Proposed AD Gulfstream requested that the FAA remove paragraphs (i)(1) and (2) of the proposed AD, which proposed to require, after performing the Part II inspection, repairing the area using a method approved by Gulfstream’s PO 00000 Frm 00008 Fmt 4700 Sfmt 4700 Organization Designation Authorization (ODA). Gulfstream stated that these paragraphs are unnecessary and redundant with normal operating and repair station procedures. Gulfstream further noted that the FAA’s regulations in 14 CFR part 43 already require that aircraft with corrosion exceeding allowable damage limits be repaired and in an airworthy state before approval for return to service. The FAA disagrees with removing paragraph (i)(2) of this AD. For corrosion that exceeds allowable damage limits, the FAA finds that the repair mandated by paragraph (i)(2) of this AD is required to address the identified unsafe condition. Aircraft found with corrosion that exceeds allowable damage limits will require corrective action that may appreciably affect the structural strength of the airframe. FAA-approved (or ODAapproved) engineering data will likely be required to return the aircraft to service. In addition, the FAA is unaware of a repair procedure or specification that could be used to approve all affected aircraft for return to service. Rather, unique, airplane-specific repairs will be necessary. However, the FAA agrees that standard maintenance practices are sufficient to repair corrosion within allowable limits and has revised paragraph (i)(1) of this AD accordingly. The FAA has also clarified the scope of the repair required after the CIC application by revising paragraph (i)(1) of this AD. Instead of the broader requirement to repair ‘‘the area,’’ that paragraph now specifies repairing ‘‘all bond line corrosion.’’ This change will decrease the burden of this requirement on operators while appropriately addressing bond line corrosion. Request To Address Airplanes Repaired Prior to AD Issuance Gulfstream requested that, for airplanes that have been ‘‘permanently’’ repaired prior to AD issuance, the FAA give operators the full benefit of the repair. Alternatively, Gulfstream suggested the FAA allow a 48-month compliance time, the same as for an airplane with allowable bond line corrosion, to avoid immediately grounding airplanes. The FAA agrees operators should have the benefit of repairs accomplished by Gulfstream before the effective date of the AD, provided Gulfstream’s ODA approves those repairs as restoring the airplane to its type certification basis. The FAA infers that by ‘‘permanent’’ repair, Gulfstream is referring to repairs to airplanes found with corrosion exceeding allowable damage limits. E:\PICKUP\03AUR1.SGM 03AUR1 Federal Register / Vol. 87, No. 148 / Wednesday, August 3, 2022 / Rules and Regulations Gulfstream has accomplished these repairs on many of the affected airplanes prior to the effective date of the AD under its ODA procedures. In the NPRM, the FAA proposed that these repairs must be made using a method approved by Gulfstream’s ODA under the procedures for alternative methods of compliance (AMOCs). In order to more efficiently give operators the benefit of these repairs, the FAA has revised paragraph (i)(2) of this AD to require an FAA-approved or ODAapproved repair method without using AMOC procedures. The document approving the repair method must still specifically reference this AD. The FAA finds that the additional compliance time requested by Gulfstream is unnecessary. Operators have 12 months after the effective date of this AD to perform the resonance CScan (Part II) inspection required by the introductory text of paragraph (i) of this AD, apply CIC, and repair any corrosion that exceeds allowable limits using an FAA-approved or ODA-approved method. Operators have this same 12month compliance time to take credit for any actions ‘‘already done’’ under paragraph (f) of this AD, including ‘‘permanent’’ repairs that Gulfstream’s ODA may need to approve by specifically referring to this AD. Request To Clarify Allowable Damage Limit Gulfstream requested that the FAA revise paragraph (i)(2) of the proposed AD to clarify that the term ‘‘allowable damage limit’’ means the allowable damage limits provided by Gulfstream as the original equipment manufacturer. Gulfstream explained that these limits are defined in various Gulfstream documents. The FAA agrees to clarify the term ‘‘allowable damage limit’’ and has revised paragraph (i)(2) of this AD to specify that the limits are those in the applicable service information or those approved by Gulfstream’s ODA. lotter on DSK11XQN23PROD with RULES1 Request To Clarify Required for Compliance (RC) Steps Gulfstream requested that the FAA revise paragraph (j)(4)(i) of the proposed AD (paragraph (k)(4)(i) of this AD) to clarify that operators only need to comply with the RC steps required by paragraph (i) of the proposed AD. Gulfstream noted that paragraph (j)(4)(i), as proposed, implies that operators would have to do all of the actions labeled ‘‘RC’’ in the customer bulletin, even though the proposed AD does not specify all of those steps. VerDate Sep<11>2014 17:44 Aug 02, 2022 Jkt 256001 The FAA agrees and has revised paragraph (k)(4)(i) of this AD accordingly. Additional Changes Made to This AD After the NPRM was issued, Gulfstream revised the portions of the ALS that are relevant to the proposed AD: Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream G500–5000 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022; Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022; and Section F and Table 12: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream V Aircraft Maintenance Manual, Revision 55, dated March 15, 2022. The FAA reviewed these revisions and determined they do not require additional work or impose any substantive changes to those proposed in the NPRM. Therefore, the FAA has revised paragraph (g) of this AD to require incorporating these later-issued revisions of the applicable section and table of Section 05–10–10 of the ALS. The FAA has also added paragraph (j) of this AD to provide credit for operators who have revised their ALS before the effective date of this AD using the ALS revisions specified in the NPRM. Subsequent paragraphs have been re-designated accordingly. The FAA has also updated the ALS table number reference in paragraphs (g)(2) and (3) of this AD. This reference changed from Table 12 to Table 11 when Gulfstream revised Section 05– 10–10 of the applicable AMMs. Conclusion The FAA reviewed the relevant data, considered any comments received, and determined that air safety requires adopting this AD as proposed. Accordingly, the FAA is issuing this AD to address the unsafe condition on these products. Except for the changes described previously, this AD is adopted as proposed in the NPRM. None of the changes will increase the economic burden on any operator. Related Service Information Under 1 CFR Part 51 The FAA reviewed Gulfstream G500– 5000 Customer Bulletin No. 190, Revision B; Gulfstream G550 Customer PO 00000 Frm 00009 Fmt 4700 Sfmt 4700 47339 Bulletin No. 190, Revision B; and Gulfstream GV Customer Bulletin No. 228, Revision B; all dated October 31, 2019. For the applicable marketing designation specified on each document, the customer bulletins specify procedures for inspecting the horizontal stabilizer lower bonded skin. The FAA also reviewed Section F and Table 12: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream V Aircraft Maintenance Manual, Revision 55, dated March 15, 2022; Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/ Maintenance Checks, of the Gulfstream G500–5000 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022; and Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/ Maintenance Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022. For the applicable marketing designation specified on each document, the service information contains inspection intervals for nondestructive testing of the lower horizontal stabilizer skins and provides the specific reference for the inspection procedures. 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 Related Service Information The FAA also reviewed the following service documents related to this final rule. • Gulfstream Service Letter Document No. GSL505510019, Revision E, dated September 3, 2021, which contains allowable damage limits for the horizontal stabilizer assembly. • Gulfstream Service Letter Document No. GSL505510020, Revision C, dated March 12, 2020, which contains procedures for applying CIC to the horizontal stabilizer. • Gulfstream V Nondestructive Testing Procedures Manual Chapter 05–00–00, 1. Horizontal Stabilizer Lower Skin Resonance C-Scan—NDT Procedure. Differences Between This AD and the Service Information The differences between Gulfstream G500–5000 Customer Bulletin No. 190, Revision B; Gulfstream G550 Customer Bulletin No. 190, Revision B; and Gulfstream V Customer Bulletin No. E:\PICKUP\03AUR1.SGM 03AUR1 47340 Federal Register / Vol. 87, No. 148 / Wednesday, August 3, 2022 / Rules and Regulations • The customer bulletins allow the horizontal stabilizer lower skin resonance C-Scan NDT inspection (referred to in the customer bulletins as a ‘‘Part II Inspection’’) and application of CIC to be repeated indefinitely every 48 months. This AD only allows the Part II inspection to be performed one time and, within 48 months after the inspection, requires approved repairs. • The customer bulletins contain actions labeled RC, and the language in the customer bulletins and in paragraph (k)(4) of this AD indicate that operators 228, Revision B; all dated October 31, 2019; and this AD are listed below. • The customer bulletins exclude certain serial-numbered airplanes inspected by Gulfstream, but this AD applies to all Model GV and GV–SP airplanes. • The customer bulletins include an optional horizontal stabilizer lower skin resonance A-Scan NDT inspection (referred to in the customer bulletins as ‘‘Part I Inspection’’) for critical areas of the horizontal stabilizer bonded lower skin assemblies, but this AD does not require the Part I Inspection. must comply with all actions labeled RC for compliance with this AD. However, this AD does not require all of the steps in the customer bulletins that are labeled as RC. Operators only need to comply with the RC steps required by paragraph (i) of this AD. Costs of Compliance The FAA estimates that this AD affects up to 694 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD: ESTIMATED COSTS Labor cost Parts cost Resonance C-Scan NDT (Part II) inspection and CIC application. AMM revision ................................................ 80 work-hours × $85 per hour = $6,800 ..... Not applicable ..... $6,800 1 work-hour × $85 per hour = $85 .............. Not applicable ..... 85 The extent of corrosion found during the inspection may vary significantly from airplane to airplane. The FAA has no way of determining the number of airplanes that might need repair or the cost to repair each airplane. 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. The 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. Regulatory Findings lotter on DSK11XQN23PROD with RULES1 Cost per airplane Action 17:44 Aug 02, 2022 (b) Affected ADs List of Subjects in 14 CFR Part 39 (d) Subject Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. The Amendment Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: PART 39—AIRWORTHINESS DIRECTIVES 1. The authority citation for part 39 continues to read as follows: ■ Authority: 49 U.S.C. 106(g), 40113, 44701. § 39.13 [Amended] 2. The FAA amends § 39.13 by adding the following new airworthiness directive: ■ 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. VerDate Sep<11>2014 For the reasons discussed above, I certify that this AD: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, (2) Will not affect intrastate aviation in Alaska, and (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. Jkt 256001 2022–16–04 Gulfstream Aerospace Corporation: Amendment 39–22133; Docket No. FAA–2021–0958; Project Identifier 2019–CE–010–AD. (a) Effective Date This airworthiness directive (AD) is effective September 7, 2022. PO 00000 Frm 00010 Fmt 4700 Sfmt 4700 Cost on U.S. operators $2,196,400 (for 323 airplanes). $58,990 (for 694 airplanes). None. (c) Applicability This AD applies to Gulfstream Aerospace Corporation Model GV and GV–SP airplanes, all serial numbers, certificated in any category. Note 1 to paragraph (c): Model GV–SP airplanes are also referred to by the marketing designations G500, G550, and G500–5000. Joint Aircraft System Component (JASC) Code 5510, Horizontal Stabilizer Structure. (e) Unsafe Condition This AD results from corrosion of the horizontal stabilizer lower bonded skin assemblies. The FAA is issuing this AD to detect and correct bond line corrosion, which if not addressed, could result in compromise of the structural integrity of the horizontal stabilizer and lead to loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Incorporation of Airworthiness Limitations (ALS) Revisions Within 30 days after the effective date of this AD, incorporate into your existing maintenance or inspection program the ALS revision specified in paragraph (g)(1), (2), or (3) of this AD for your applicable airplane designation. (1) For Model GV airplanes: Section F and Table 12: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/ Maintenance Checks, of the Gulfstream V Aircraft Maintenance Manual, Revision 55, dated March 15, 2022. E:\PICKUP\03AUR1.SGM 03AUR1 Federal Register / Vol. 87, No. 148 / Wednesday, August 3, 2022 / Rules and Regulations (2) For Model GV–SP (G500 and G500– 5000) airplanes: Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/ Maintenance Checks, of the Gulfstream G500–5000 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022. (3) For Model GV–SP (G550) airplanes: Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022. lotter on DSK11XQN23PROD with RULES1 (h) Applicable Customer Bulletins The customer bulletins specified in paragraphs (h)(1) through (3) of this AD contain procedures for compliance with the actions required by paragraph (i) of this AD for your applicable airplane designation: (1) Gulfstream GV Customer Bulletin No. 228, Revision B, dated October 31, 2019; (2) Gulfstream G500–5000 Customer Bulletin No. 190, Revision B, dated October 31, 2019; or (3) Gulfstream G550 Customer Bulletin No. 190, Revision B, dated October 31, 2019. (i) Inspection For Model GV airplanes, all serial numbers, and Model GV–SP airplanes, serial numbers 5001 through 5158: Within 12 months after the effective date of this AD, perform the horizontal stabilizer lower skin resonance C-Scan inspection (Part II inspection) for bond line corrosion and apply corrosion inhibiting compound (CIC) by following steps 6.2.a. through 6.2.e. and 6.3.a. of appendix A of the applicable customer bulletin listed in paragraph (h) of this AD. Note 2 to the introductory text of paragraph (i): Operators may align the inspections listed in the applicable ALS revision in paragraph (g) of this AD with the Part II inspection. (1) Within 48 months after applying CIC, repair all bond line corrosion. (2) If there is bond line corrosion that exceeds the allowable damage limits in Table 2 of appendix A of the applicable customer bulletin listed in paragraph (h) of this AD, or other allowable damage limits established by an appropriately authorized Gulfstream Organization Designation Authorization (ODA) unit member, repair all bond line corrosion before further flight using a repair approved by the FAA or an appropriately authorized Gulfstream ODA unit member. (i) For a repair method to be approved by the FAA, the FAA’s approval of the repair must specifically refer to this AD. (ii) For a repair method to be approved by a Gulfstream ODA unit member, the unit member must be authorized in writing by the Manager of the Atlanta ACO Branch to approve repairs for this AD, and the unit member’s approval of the repair must specifically refer to this AD. (j) Credit for Previous Actions You may take credit for the ALS revision required by paragraph (g) of this AD if you revised the ALS before the effective date of this AD using the service information VerDate Sep<11>2014 17:44 Aug 02, 2022 Jkt 256001 specified in paragraph (j)(1), (2), or (3) of this AD, as applicable to your airplane designation. (1) For Model GV airplanes: Section F and Table 12: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/ Maintenance Checks, of the Gulfstream V Aircraft Maintenance Manual, Revision 53, dated February 28, 2020. (2) For Model GV–SP (G500 and G500– 5000) airplanes: Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/ Maintenance Checks, of the Gulfstream G500–5000 Aircraft Maintenance Manual, Revision 34, dated March 15, 2021. (3) For Model GV–SP (G550) airplanes: Section F and Table 12: Horizontal Stabilizer Inspection Table in Section 05–10–10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 34, dated March 15, 2021. (k) Alternative Methods of Compliance (AMOCs) (1) The Manager, Atlanta ACO Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in paragraph (l)(1) of this AD. (2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/ certificate holding district office. (3) An AMOC that provides an acceptable level of safety may be used for any repair, modification, or alteration required by this AD if it is approved by a Gulfstream Engineering Authorized Representative (EAR) of the Gulfstream ODA that has been authorized by the Manager, Atlanta ACO Branch, to make those findings. To be approved, the repair, modification deviation, or alteration deviation must meet the certification basis of the airplane, and the approval must specifically refer to this AD. (4) For service information that contains steps that are labeled as Required for Compliance (RC), the following provisions apply. (i) The steps labeled as RC, including substeps under an RC step and any figures identified in an RC step, that are required by paragraph (i) of this AD must be done to comply with this AD. An AMOC is required for any deviations to RC steps required by paragraph (i) of this AD, including substeps and identified figures. (ii) Steps not labeled as RC may be deviated from using accepted methods in accordance with the operator’s maintenance or inspection program without obtaining approval of an AMOC, provided the RC steps, including substeps and identified figures, can still be done as specified, and the airplane can be put back in an airworthy condition. PO 00000 Frm 00011 Fmt 4700 Sfmt 9990 47341 (l) Related Information (1) For more information about this AD, contact Ronald Wissing, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: (404) 474–5552; email: 9-ASOATLACO-ADs@faa.gov. (2) Service information identified in this AD that is not incorporated by reference is available at the addresses specified in paragraphs (m)(3) and (4) of this AD. (m) Material Incorporated by Reference (1) The Director of the Federal Register approved the incorporation by reference of the service information listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51. (2) You must use this service information as applicable to do the actions required by this AD, unless the AD specifies otherwise. (i) Gulfstream G500–5000 Customer Bulletin No. 190, Revision B, dated October 31, 2019. (ii) Gulfstream G550 Customer Bulletin No. 190, Revision B, dated October 31, 2019. (iii) Gulfstream GV Customer Bulletin No. 228, Revision B, dated October 31, 2019. (iv) Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10– 10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream G500–5000 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022. (v) Section F and Table 11: Horizontal Stabilizer Inspection Table in Section 05–10– 10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 36, dated March 15, 2022. (vi) Section F and Table 12: Horizontal Stabilizer Inspection Table in Section 05–10– 10, Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream V Aircraft Maintenance Manual, Revision 55, dated March 15, 2022. (3) For service information identified in this AD, contact Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA 31402; phone: (800) 810–4853; fax: (912) 965–3520; email: pubs@gulfstream.com; website: www.gulfstream.com/en/customer-support/. (4) You may view this service information at FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call (817) 222–5110. (5) You may view this service information that is incorporated by reference at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, email: fr.inspection@nara.gov, or go to: www.archives.gov/federal-register/cfr/ibrlocations.html. Issued on July 26, 2022. Christina Underwood, Acting Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2022–16535 Filed 8–2–22; 8:45 am] BILLING CODE 4910–13–P E:\PICKUP\03AUR1.SGM 03AUR1

Agencies

[Federal Register Volume 87, Number 148 (Wednesday, August 3, 2022)]
[Rules and Regulations]
[Pages 47337-47341]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-16535]



[[Page 47337]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0958; Project Identifier 2019-CE-010-AD; Amendment 
39-22133; AD 2022-16-04]
RIN 2120-AA64


Airworthiness Directives; Gulfstream Aerospace Corporation 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
Gulfstream Aerospace Corporation (Gulfstream) Model GV and GV-SP 
airplanes. This AD was prompted by corrosion of the horizontal 
stabilizer lower bonded skin assemblies. This AD requires inspecting 
the horizontal stabilizer lower skin and associated bonded doublers and 
bonded stringers, repairing any area with corrosion beyond allowable 
damage limits, and incorporating revisions to the airworthiness 
limitations section (ALS) in the existing aircraft maintenance manual 
(AMM) or progressive maintenance program. The FAA is issuing this AD to 
address the unsafe condition on these products.

DATES: This AD is effective September 7, 2022.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of September 7, 
2022.

ADDRESSES: For service information identified in this final rule, 
contact Gulfstream Aerospace Corporation, Technical Publications Dept., 
P.O. Box 2206, Savannah, GA 31402; phone: (800) 810-4853; fax: (912) 
965-3520; email: [email protected]; website: www.gulfstream.com/en/customer-support/. You may view this service information at the FAA, 
Airworthiness Products Section, Operational Safety Branch, 901 Locust, 
Kansas City, MO 64106. For information on the availability of this 
material at the FAA, call (817) 222-5110. It is also available at 
www.regulations.gov by searching for and locating Docket No. FAA-2021-
0958.

Examining the AD Docket

    You may examine the AD docket at www.regulations.gov by searching 
for and locating Docket No. FAA-2021-0958; or in person at Docket 
Operations between 9 a.m. and 5 p.m., Monday through Friday, except 
Federal holidays. The AD docket contains this final rule, any comments 
received, and other information. The address for Docket Operations is 
U.S. Department of Transportation, Docket Operations, M-30, West 
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, 
Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT: Ronald Wissing, Aviation Safety 
Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, 
GA 30337; phone: (404) 474-5552; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Background

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 by adding an AD that would apply to all Gulfstream Model GV 
and GV-SP airplanes. The NPRM published in the Federal Register on 
November 5, 2021 (86 FR 61088). The NPRM was prompted by bond line 
corrosion on Model GV and GV-SP airplanes, which causes disbonding 
between the horizontal stabilizer lower skin and associated bonded 
doublers and bonded stringers. Gulfstream determined that the existing 
visual inspection in the AMM did not reliably detect bond line 
corrosion and added a repetitive non-destructive testing (NDT) 
inspection to detect the damage. In the NPRM, the FAA proposed to 
require inspecting the horizontal stabilizer lower skin and associated 
bonded doublers and bonded stringers, repairing any area with corrosion 
beyond allowable damage limits, and incorporating revisions to the ALS 
in the existing AMM. The FAA is issuing this AD to address the unsafe 
condition on these products.

Discussion of Final Airworthiness Directive

Comments

    The FAA received comments from one commenter, Gulfstream. The 
following presents the comments received on the NPRM and the FAA's 
response to each comment.

Request To Clarify Information in the Preamble

    Gulfstream requested that the FAA revise a phrase describing part 
of the proposed corrective action under SUMMARY and under the 
``Proposed AD Requirements in This NPRM'' section of SUPPLEMENTARY 
INFORMATION. Gulfstream requested the FAA change ``repairing the area 
susceptible to corrosion'' to ``identify if a repair is required.'' 
Gulfstream stated that the bonded structure is ``susceptible'' to 
corrosion but does not necessarily require ``repair'' because the need 
for repair is based on the inspection results.
    The FAA agrees that all areas susceptible to corrosion do not 
necessarily require repair. The FAA has revised the SUMMARY of this 
final rule to clarify that only areas with corrosion that exceeds 
allowable damage limits need to be repaired. The ``Proposed AD 
Requirements in This NPRM'' section is not restated in this final rule, 
so a change is unnecessary.

Request To Revise the Description of a Service Document

    Gulfstream requested the FAA change the description of Gulfstream 
Service Letter Document No. GSL505510019, Revision E, dated September 
3, 2021, in the ``Other Related Service Information'' section of the 
preamble. In the NPRM, the FAA stated that the service letter contains 
procedures for applying on-wing corrosion inhibiting compound (CIC) to 
the horizontal stabilizer. Gulfstream advised that this description is 
inaccurate because although the service letter specifies applying CIC, 
it references another service letter for the application instructions. 
Gulfstream requested that the preamble state instead that this service 
letter ``contains allowable damage limits for the horizontal stabilizer 
assembly.''
    The FAA agrees and has revised this final rule accordingly.

Request Regarding the Airplane Effectivity Range

    Gulfstream requested that the FAA remove language in the preamble 
explaining that the proposed AD would apply to all Model GV and GV-SP 
airplanes, while the service bulletins exclude certain serial-numbered 
airplanes. Gulfstream also requested that the inspection proposed in 
paragraph (i) of the proposed AD not be required for these same serial-
numbered airplanes. Gulfstream stated that four airplanes were excluded 
from the effectivity of the customer bulletin because the airplanes had 
not yet reached the baseline compliance time for doing the initial 
``Part II'' inspection of the horizontal stabilizer lower skin. 
Gulfstream explained that removing those four airplanes from the 
inspection portion of the proposed AD would not have an impact on 
safety, because those airplanes will be inspected in accordance with 
the 144-month entry into service inspection specified in Chapter 5 of 
the AMM.
    The FAA disagrees. Gulfstream's request appears to be based on the 
compliance time for those four airplanes and not whether they are 
subject to the unsafe condition identified in this AD.

[[Page 47338]]

The inspection required by paragraph (i) of this AD is necessary to 
correct the unsafe condition on all Model GV-SP airplanes with a serial 
number in the range of 5001 through 5158. The FAA did not change this 
AD based on this comment.

Request To Include Terminating Action

    Gulfstream requested that the FAA add terminating actions for the 
ALS revision proposed in paragraph (g) and for the inspection proposed 
in paragraph (i) of the proposed AD. Gulfstream stated that otherwise 
owners will have to comply for an indefinite period.
    The FAA does not agree because paragraphs (g) and (i) of this AD 
require one-time actions and not repetitive actions; therefore, 
terminating action is not necessary. Once an operator has revised the 
maintenance or inspection program for its airplane by incorporating the 
applicable ALS revision, the operator has complied with paragraph (g) 
of this AD. As explained in the NPRM, although the service bulletins 
allow the inspection to be repeated indefinitely every 48 months, this 
AD does not. Instead, paragraph (i) of this AD requires the inspection 
once, and any necessary repairs within 48 months after the inspection. 
The FAA did not change this AD based on this comment.

Request To Remove Entry Into Service Criteria

    Gulfstream requested that the FAA revise paragraph (i) of the 
proposed AD to remove the criteria that the inspection be required for 
airplanes ``where more than 132 months have elapsed since the original 
certificate of airworthiness issue date (often referred to as entry 
into service date).'' In support, Gulfstream explained that this 
language is no longer applicable because all affected airplanes have 
accumulated 132 months since entry into service. In addition, 
Gulfstream noted that the entry into service date and the original 
certificate of airworthiness issue date are two different dates and are 
not interchangeable.
    The FAA agrees and has revised paragraph (i) of this AD 
accordingly.

Request To Remove Note Regarding ALS Inspections

    Gulfstream requested that the FAA remove Note 2 to the introductory 
text of paragraph (i) of the proposed AD, which advised that the 
inspections listed in the ALS revision (required by paragraph (g) of 
the proposed AD) must be done at the same time as the Part II 
inspection. Gulfstream stated it is not necessary to mandate the ALS 
maintenance inspections at the same time as the Part II inspection of 
the horizontal stabilizer lower skin for bond line corrosion. 
Gulfstream explained there is no reason to accomplish these actions 
together and doing so could result in duplication of efforts.
    The FAA agrees that, to correct the unsafe condition, the ALS 
maintenance inspections are not required at the same time as the 
airworthiness inspection of the horizontal stabilizer lower skin for 
bond line corrosion. However, operators may align these inspections to 
establish a baseline for the required repetitive inspection intervals. 
The FAA has revised Note 2 to the introductory text of paragraph (i) of 
this AD accordingly.

Request To Clarify Note 2 of the Proposed AD

    Gulfstream requested the FAA clarify the intent and placement of 
Note 2, which was located after the introductory text of paragraph (i) 
of the proposed AD and before paragraphs (i)(1) and (2) of the proposed 
AD. Gulfstream explained that due to the placement of the note, it is 
unclear whether paragraphs (i)(1) and (2) of the proposed AD are part 
of the note or whether they are lower level paragraphs of paragraph (i) 
of the proposed AD. Gulfstream also stated that this note does not 
follow FAA policy and guidance, which states that notes are for 
informational purposes, because it introduces a requirement not 
otherwise stated in the AD.
    Paragraphs (i)(1) and (2) of this AD are lower level paragraphs of 
paragraph (i) of this AD. Paragraph (i) of this AD requires inspecting 
the horizontal stabilizer lower skin for bond line corrosion and 
applying CIC. Paragraphs (i)(1) and (2) of this AD provide the 
compliance time for repairing any corrosion found as a result of the 
inspection: either within 48 months after applying CIC if the corrosion 
is within allowable damage limits, or before further flight if any 
corrosion exceeds allowable damage limits. The placement of the note 
after the introductory text of paragraph (i) of this AD follows the 
formatting requirements for regulatory documents in the Office of the 
Federal Register's Document Drafting Handbook. The FAA did not change 
this AD based on this comment.

Request To Remove Paragraphs (i)(1) and (2) of the Proposed AD

    Gulfstream requested that the FAA remove paragraphs (i)(1) and (2) 
of the proposed AD, which proposed to require, after performing the 
Part II inspection, repairing the area using a method approved by 
Gulfstream's Organization Designation Authorization (ODA). Gulfstream 
stated that these paragraphs are unnecessary and redundant with normal 
operating and repair station procedures. Gulfstream further noted that 
the FAA's regulations in 14 CFR part 43 already require that aircraft 
with corrosion exceeding allowable damage limits be repaired and in an 
airworthy state before approval for return to service.
    The FAA disagrees with removing paragraph (i)(2) of this AD. For 
corrosion that exceeds allowable damage limits, the FAA finds that the 
repair mandated by paragraph (i)(2) of this AD is required to address 
the identified unsafe condition. Aircraft found with corrosion that 
exceeds allowable damage limits will require corrective action that may 
appreciably affect the structural strength of the airframe. FAA-
approved (or ODA-approved) engineering data will likely be required to 
return the aircraft to service. In addition, the FAA is unaware of a 
repair procedure or specification that could be used to approve all 
affected aircraft for return to service. Rather, unique, airplane-
specific repairs will be necessary.
    However, the FAA agrees that standard maintenance practices are 
sufficient to repair corrosion within allowable limits and has revised 
paragraph (i)(1) of this AD accordingly. The FAA has also clarified the 
scope of the repair required after the CIC application by revising 
paragraph (i)(1) of this AD. Instead of the broader requirement to 
repair ``the area,'' that paragraph now specifies repairing ``all bond 
line corrosion.'' This change will decrease the burden of this 
requirement on operators while appropriately addressing bond line 
corrosion.

Request To Address Airplanes Repaired Prior to AD Issuance

    Gulfstream requested that, for airplanes that have been 
``permanently'' repaired prior to AD issuance, the FAA give operators 
the full benefit of the repair. Alternatively, Gulfstream suggested the 
FAA allow a 48-month compliance time, the same as for an airplane with 
allowable bond line corrosion, to avoid immediately grounding 
airplanes.
    The FAA agrees operators should have the benefit of repairs 
accomplished by Gulfstream before the effective date of the AD, 
provided Gulfstream's ODA approves those repairs as restoring the 
airplane to its type certification basis. The FAA infers that by 
``permanent'' repair, Gulfstream is referring to repairs to airplanes 
found with corrosion exceeding allowable damage limits.

[[Page 47339]]

Gulfstream has accomplished these repairs on many of the affected 
airplanes prior to the effective date of the AD under its ODA 
procedures. In the NPRM, the FAA proposed that these repairs must be 
made using a method approved by Gulfstream's ODA under the procedures 
for alternative methods of compliance (AMOCs). In order to more 
efficiently give operators the benefit of these repairs, the FAA has 
revised paragraph (i)(2) of this AD to require an FAA-approved or ODA-
approved repair method without using AMOC procedures. The document 
approving the repair method must still specifically reference this AD.
    The FAA finds that the additional compliance time requested by 
Gulfstream is unnecessary. Operators have 12 months after the effective 
date of this AD to perform the resonance C-Scan (Part II) inspection 
required by the introductory text of paragraph (i) of this AD, apply 
CIC, and repair any corrosion that exceeds allowable limits using an 
FAA-approved or ODA-approved method. Operators have this same 12-month 
compliance time to take credit for any actions ``already done'' under 
paragraph (f) of this AD, including ``permanent'' repairs that 
Gulfstream's ODA may need to approve by specifically referring to this 
AD.

Request To Clarify Allowable Damage Limit

    Gulfstream requested that the FAA revise paragraph (i)(2) of the 
proposed AD to clarify that the term ``allowable damage limit'' means 
the allowable damage limits provided by Gulfstream as the original 
equipment manufacturer. Gulfstream explained that these limits are 
defined in various Gulfstream documents.
    The FAA agrees to clarify the term ``allowable damage limit'' and 
has revised paragraph (i)(2) of this AD to specify that the limits are 
those in the applicable service information or those approved by 
Gulfstream's ODA.

Request To Clarify Required for Compliance (RC) Steps

    Gulfstream requested that the FAA revise paragraph (j)(4)(i) of the 
proposed AD (paragraph (k)(4)(i) of this AD) to clarify that operators 
only need to comply with the RC steps required by paragraph (i) of the 
proposed AD. Gulfstream noted that paragraph (j)(4)(i), as proposed, 
implies that operators would have to do all of the actions labeled 
``RC'' in the customer bulletin, even though the proposed AD does not 
specify all of those steps.
    The FAA agrees and has revised paragraph (k)(4)(i) of this AD 
accordingly.

Additional Changes Made to This AD

    After the NPRM was issued, Gulfstream revised the portions of the 
ALS that are relevant to the proposed AD: Section F and Table 11: 
Horizontal Stabilizer Inspection Table in Section 05-10-10, 
Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance 
Checks, of the Gulfstream G500-5000 Aircraft Maintenance Manual, 
Revision 36, dated March 15, 2022; Section F and Table 11: Horizontal 
Stabilizer Inspection Table in Section 05-10-10, Airworthiness 
Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the 
Gulfstream G550 Aircraft Maintenance Manual, Revision 36, dated March 
15, 2022; and Section F and Table 12: Horizontal Stabilizer Inspection 
Table in Section 05-10-10, Airworthiness Limitations, of Chapter 05, 
Time Limits/Maintenance Checks, of the Gulfstream V Aircraft 
Maintenance Manual, Revision 55, dated March 15, 2022. The FAA reviewed 
these revisions and determined they do not require additional work or 
impose any substantive changes to those proposed in the NPRM. 
Therefore, the FAA has revised paragraph (g) of this AD to require 
incorporating these later-issued revisions of the applicable section 
and table of Section 05-10-10 of the ALS. The FAA has also added 
paragraph (j) of this AD to provide credit for operators who have 
revised their ALS before the effective date of this AD using the ALS 
revisions specified in the NPRM. Subsequent paragraphs have been re-
designated accordingly.
    The FAA has also updated the ALS table number reference in 
paragraphs (g)(2) and (3) of this AD. This reference changed from Table 
12 to Table 11 when Gulfstream revised Section 05-10-10 of the 
applicable AMMs.

Conclusion

    The FAA reviewed the relevant data, considered any comments 
received, and determined that air safety requires adopting this AD as 
proposed. Accordingly, the FAA is issuing this AD to address the unsafe 
condition on these products. Except for the changes described 
previously, this AD is adopted as proposed in the NPRM. None of the 
changes will increase the economic burden on any operator.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Gulfstream G500-5000 Customer Bulletin No. 190, 
Revision B; Gulfstream G550 Customer Bulletin No. 190, Revision B; and 
Gulfstream GV Customer Bulletin No. 228, Revision B; all dated October 
31, 2019. For the applicable marketing designation specified on each 
document, the customer bulletins specify procedures for inspecting the 
horizontal stabilizer lower bonded skin.
    The FAA also reviewed Section F and Table 12: Horizontal Stabilizer 
Inspection Table in Section 05-10-10, Airworthiness Limitations, of 
Chapter 05, Time Limits/Maintenance Checks, of the Gulfstream V 
Aircraft Maintenance Manual, Revision 55, dated March 15, 2022; Section 
F and Table 11: Horizontal Stabilizer Inspection Table in Section 05-
10-10, Airworthiness Limitations, of Chapter 05, Time Limits/
Maintenance Checks, of the Gulfstream G500-5000 Aircraft Maintenance 
Manual, Revision 36, dated March 15, 2022; and Section F and Table 11: 
Horizontal Stabilizer Inspection Table in Section 05-10-10, 
Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance 
Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 
36, dated March 15, 2022. For the applicable marketing designation 
specified on each document, the service information contains inspection 
intervals for nondestructive testing of the lower horizontal stabilizer 
skins and provides the specific reference for the inspection 
procedures.
    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 Related Service Information

    The FAA also reviewed the following service documents related to 
this final rule.
     Gulfstream Service Letter Document No. GSL505510019, 
Revision E, dated September 3, 2021, which contains allowable damage 
limits for the horizontal stabilizer assembly.
     Gulfstream Service Letter Document No. GSL505510020, 
Revision C, dated March 12, 2020, which contains procedures for 
applying CIC to the horizontal stabilizer.
     Gulfstream V Nondestructive Testing Procedures Manual 
Chapter 05-00-00, 1. Horizontal Stabilizer Lower Skin Resonance C-
Scan--NDT Procedure.

Differences Between This AD and the Service Information

    The differences between Gulfstream G500-5000 Customer Bulletin No. 
190, Revision B; Gulfstream G550 Customer Bulletin No. 190, Revision B; 
and Gulfstream V Customer Bulletin No.

[[Page 47340]]

228, Revision B; all dated October 31, 2019; and this AD are listed 
below.
     The customer bulletins exclude certain serial-numbered 
airplanes inspected by Gulfstream, but this AD applies to all Model GV 
and GV-SP airplanes.
     The customer bulletins include an optional horizontal 
stabilizer lower skin resonance A-Scan NDT inspection (referred to in 
the customer bulletins as ``Part I Inspection'') for critical areas of 
the horizontal stabilizer bonded lower skin assemblies, but this AD 
does not require the Part I Inspection.
     The customer bulletins allow the horizontal stabilizer 
lower skin resonance C-Scan NDT inspection (referred to in the customer 
bulletins as a ``Part II Inspection'') and application of CIC to be 
repeated indefinitely every 48 months. This AD only allows the Part II 
inspection to be performed one time and, within 48 months after the 
inspection, requires approved repairs.
     The customer bulletins contain actions labeled RC, and the 
language in the customer bulletins and in paragraph (k)(4) of this AD 
indicate that operators must comply with all actions labeled RC for 
compliance with this AD. However, this AD does not require all of the 
steps in the customer bulletins that are labeled as RC. Operators only 
need to comply with the RC steps required by paragraph (i) of this AD.

Costs of Compliance

    The FAA estimates that this AD affects up to 694 airplanes of U.S. 
registry. The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                              Cost per
            Action                  Labor cost            Parts cost          airplane   Cost on U.S.  operators
----------------------------------------------------------------------------------------------------------------
Resonance C-Scan NDT (Part II)  80 work-hours x    Not applicable..........      $6,800  $2,196,400 (for 323
 inspection and CIC              $85 per hour =                                           airplanes).
 application.                    $6,800.
AMM revision..................  1 work-hour x $85  Not applicable..........          85  $58,990 (for 694
                                 per hour = $85.                                          airplanes).
----------------------------------------------------------------------------------------------------------------

    The extent of corrosion found during the inspection may vary 
significantly from airplane to airplane. The FAA has no way of 
determining the number of airplanes that might need repair or the cost 
to repair each airplane.

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.
    The 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.

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) Will not affect intrastate aviation in Alaska, and
    (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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13   [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2022-16-04 Gulfstream Aerospace Corporation: Amendment 39-22133; 
Docket No. FAA-2021-0958; Project Identifier 2019-CE-010-AD.

(a) Effective Date

    This airworthiness directive (AD) is effective September 7, 
2022.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Gulfstream Aerospace Corporation Model GV and 
GV-SP airplanes, all serial numbers, certificated in any category.
    Note 1 to paragraph (c): Model GV-SP airplanes are also referred 
to by the marketing designations G500, G550, and G500-5000.

(d) Subject

    Joint Aircraft System Component (JASC) Code 5510, Horizontal 
Stabilizer Structure.

(e) Unsafe Condition

    This AD results from corrosion of the horizontal stabilizer 
lower bonded skin assemblies. The FAA is issuing this AD to detect 
and correct bond line corrosion, which if not addressed, could 
result in compromise of the structural integrity of the horizontal 
stabilizer and lead to loss of control of the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

 (g) Incorporation of Airworthiness Limitations (ALS) Revisions

    Within 30 days after the effective date of this AD, incorporate 
into your existing maintenance or inspection program the ALS 
revision specified in paragraph (g)(1), (2), or (3) of this AD for 
your applicable airplane designation.
    (1) For Model GV airplanes: Section F and Table 12: Horizontal 
Stabilizer Inspection Table in Section 05-10-10, Airworthiness 
Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the 
Gulfstream V Aircraft Maintenance Manual, Revision 55, dated March 
15, 2022.

[[Page 47341]]

    (2) For Model GV-SP (G500 and G500-5000) airplanes: Section F 
and Table 11: Horizontal Stabilizer Inspection Table in Section 05-
10-10, Airworthiness Limitations, of Chapter 05, Time Limits/
Maintenance Checks, of the Gulfstream G500-5000 Aircraft Maintenance 
Manual, Revision 36, dated March 15, 2022.
    (3) For Model GV-SP (G550) airplanes: Section F and Table 11: 
Horizontal Stabilizer Inspection Table in Section 05-10-10, 
Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance 
Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 
36, dated March 15, 2022.

 (h) Applicable Customer Bulletins

    The customer bulletins specified in paragraphs (h)(1) through 
(3) of this AD contain procedures for compliance with the actions 
required by paragraph (i) of this AD for your applicable airplane 
designation:
    (1) Gulfstream GV Customer Bulletin No. 228, Revision B, dated 
October 31, 2019;
    (2) Gulfstream G500-5000 Customer Bulletin No. 190, Revision B, 
dated October 31, 2019; or
    (3) Gulfstream G550 Customer Bulletin No. 190, Revision B, dated 
October 31, 2019.

(i) Inspection

    For Model GV airplanes, all serial numbers, and Model GV-SP 
airplanes, serial numbers 5001 through 5158: Within 12 months after 
the effective date of this AD, perform the horizontal stabilizer 
lower skin resonance C-Scan inspection (Part II inspection) for bond 
line corrosion and apply corrosion inhibiting compound (CIC) by 
following steps 6.2.a. through 6.2.e. and 6.3.a. of appendix A of 
the applicable customer bulletin listed in paragraph (h) of this AD.
    Note 2 to the introductory text of paragraph (i): Operators may 
align the inspections listed in the applicable ALS revision in 
paragraph (g) of this AD with the Part II inspection.
    (1) Within 48 months after applying CIC, repair all bond line 
corrosion.
    (2) If there is bond line corrosion that exceeds the allowable 
damage limits in Table 2 of appendix A of the applicable customer 
bulletin listed in paragraph (h) of this AD, or other allowable 
damage limits established by an appropriately authorized Gulfstream 
Organization Designation Authorization (ODA) unit member, repair all 
bond line corrosion before further flight using a repair approved by 
the FAA or an appropriately authorized Gulfstream ODA unit member.
    (i) For a repair method to be approved by the FAA, the FAA's 
approval of the repair must specifically refer to this AD.
    (ii) For a repair method to be approved by a Gulfstream ODA unit 
member, the unit member must be authorized in writing by the Manager 
of the Atlanta ACO Branch to approve repairs for this AD, and the 
unit member's approval of the repair must specifically refer to this 
AD.

(j) Credit for Previous Actions

    You may take credit for the ALS revision required by paragraph 
(g) of this AD if you revised the ALS before the effective date of 
this AD using the service information specified in paragraph (j)(1), 
(2), or (3) of this AD, as applicable to your airplane designation.
    (1) For Model GV airplanes: Section F and Table 12: Horizontal 
Stabilizer Inspection Table in Section 05-10-10, Airworthiness 
Limitations, of Chapter 05, Time Limits/Maintenance Checks, of the 
Gulfstream V Aircraft Maintenance Manual, Revision 53, dated 
February 28, 2020.
    (2) For Model GV-SP (G500 and G500-5000) airplanes: Section F 
and Table 11: Horizontal Stabilizer Inspection Table in Section 05-
10-10, Airworthiness Limitations, of Chapter 05, Time Limits/
Maintenance Checks, of the Gulfstream G500-5000 Aircraft Maintenance 
Manual, Revision 34, dated March 15, 2021.
    (3) For Model GV-SP (G550) airplanes: Section F and Table 12: 
Horizontal Stabilizer Inspection Table in Section 05-10-10, 
Airworthiness Limitations, of Chapter 05, Time Limits/Maintenance 
Checks, of the Gulfstream G550 Aircraft Maintenance Manual, Revision 
34, dated March 15, 2021.

(k) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Atlanta ACO Branch, FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request 
to your principal inspector or local Flight Standards District 
Office, as appropriate. If sending information directly to the 
manager of the certification office, send it to the attention of the 
person identified in paragraph (l)(1) of this AD.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair, modification, or alteration required by this AD 
if it is approved by a Gulfstream Engineering Authorized 
Representative (EAR) of the Gulfstream ODA that has been authorized 
by the Manager, Atlanta ACO Branch, to make those findings. To be 
approved, the repair, modification deviation, or alteration 
deviation must meet the certification basis of the airplane, and the 
approval must specifically refer to this AD.
    (4) For service information that contains steps that are labeled 
as Required for Compliance (RC), the following provisions apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, that are required by 
paragraph (i) of this AD must be done to comply with this AD. An 
AMOC is required for any deviations to RC steps required by 
paragraph (i) of this AD, including substeps and identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(l) Related Information

    (1) For more information about this AD, contact Ronald Wissing, 
Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia 
Avenue, College Park, GA 30337; phone: (404) 474-5552; email: [email protected].
    (2) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (m)(3) and (4) of this AD.

(m) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Gulfstream G500-5000 Customer Bulletin No. 190, Revision B, 
dated October 31, 2019.
    (ii) Gulfstream G550 Customer Bulletin No. 190, Revision B, 
dated October 31, 2019.
    (iii) Gulfstream GV Customer Bulletin No. 228, Revision B, dated 
October 31, 2019.
    (iv) Section F and Table 11: Horizontal Stabilizer Inspection 
Table in Section 05-10-10, Airworthiness Limitations, of Chapter 05, 
Time Limits/Maintenance Checks, of the Gulfstream G500-5000 Aircraft 
Maintenance Manual, Revision 36, dated March 15, 2022.
    (v) Section F and Table 11: Horizontal Stabilizer Inspection 
Table in Section 05-10-10, Airworthiness Limitations, of Chapter 05, 
Time Limits/Maintenance Checks, of the Gulfstream G550 Aircraft 
Maintenance Manual, Revision 36, dated March 15, 2022.
    (vi) Section F and Table 12: Horizontal Stabilizer Inspection 
Table in Section 05-10-10, Airworthiness Limitations, of Chapter 05, 
Time Limits/Maintenance Checks, of the Gulfstream V Aircraft 
Maintenance Manual, Revision 55, dated March 15, 2022.
    (3) For service information identified in this AD, contact 
Gulfstream Aerospace Corporation, Technical Publications Dept., P.O. 
Box 2206, Savannah, GA 31402; phone: (800) 810-4853; fax: (912) 965-
3520; email: [email protected]; website: www.gulfstream.com/en/customer-support/.
    (4) You may view this service information at FAA, Airworthiness 
Products Section, Operational Safety Branch, 901 Locust, Kansas 
City, MO 64106. For information on the availability of this material 
at the FAA, call (817) 222-5110.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: [email protected], or go to: www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on July 26, 2022.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2022-16535 Filed 8-2-22; 8:45 am]
BILLING CODE 4910-13-P


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