Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, Inc.) Airplanes, 20461-20465 [2021-08053]

Download as PDF Federal Register / Vol. 86, No. 74 / Tuesday, April 20, 2021 / Proposed Rules 2021–0312; Project Identifier MCAI– 2020–01376–T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by June 4, 2021. (b) Affected ADs None. (c) Applicability This AD applies to De Havilland Aircraft of Canada Limited (type certificate previously held by Bombardier, Inc.) airplanes, certificated in any category, and identified in paragraphs (c)(1) through (4) of this AD. (1) Model DHC–8–102, –103, and –106 airplanes, as identified in De Havilland Service Bulletin 8–27–123, Revision A, dated September 8, 2020. (2) Model DHC–8–201 and –202 airplanes, as identified in De Havilland Service Bulletin 8–27–123, Revision A, dated September 8, 2020. (3) Model DHC–8–301, –311, and –315 airplanes, as identified in De Havilland Service Bulletin 8–27–123, Revision A, dated September 8, 2020. (4) Model DHC–8–400, –401, and –402 airplanes, as identified in De Havilland Service Bulletin 84–27–74, Revision B, dated September 8, 2020. (d) Subject Air Transport Association (ATA) of America Code 27, Flight controls. (e) Unsafe Condition This AD was prompted by reports that mounting nuts attaching the rudder actuator bracket to the vertical stabilizer have been found cracked or missing due to hydrogen embrittlement. The FAA is issuing this AD to address the possible loss of the rudder actuator bracket, which could result in a dormant disconnection between the rudder actuator and the vertical stabilizer. This condition, if not addressed, could result in a loss of directional control of the aircraft. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Required Actions Within 8,000 flight hours or 4 years, whichever is earlier, after the effective date of this AD: Do a detailed visual inspection of the rudder actuator bracket mounting nuts for missing nuts or corrosion, cracking, or other damage, in accordance with the Accomplishment Instructions of De Havilland Service Bulletin 8–27–123, Revision A, dated September 8, 2020; or De Havilland Service Bulletin 84–27–74, Revision B, dated September 8, 2020; as applicable. If any missing nuts or corrosion, cracking, or other damage is found, replace the nuts before further flight, in accordance with the Accomplishment Instructions of De Havilland Service Bulletin 8–27–123, Revision A, dated September 8, 2020; or De Havilland Service Bulletin 84–27–74, Revision B, dated September 8, 2020; as applicable. VerDate Sep<11>2014 16:17 Apr 19, 2021 Jkt 253001 (h) Credit for Previous Actions This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using De Havilland Service Bulletin 8–27–123, dated December 20, 2019; De Havilland Service Bulletin 84–27–74, dated December 20, 2019; or De Havilland Service Bulletin 84–27–74, Revision A, dated January 20, 2020; as applicable. (i) No Reporting Requirement Although De Havilland Service Bulletin 8– 27–123, Revision A, dated September 8, 2020; and De Havilland Service Bulletin 84– 27–74, Revision B, dated September 8, 2020, specify to submit certain information to the manufacturer, this AD does not include that requirement. (j) Other FAA AD Provisions The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, New York 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 responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the certification office, send it to ATTN: Program Manager, Continuing Operational Safety, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7300; fax 516–794–5531. Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the responsible Flight Standards Office. (2) Contacting the Manufacturer: For any requirement in this AD to obtain instructions from a manufacturer, the instructions must be accomplished using a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada Civil Aviation (TCCA); or De Havilland Aircraft of Canada Limited’s TCCA Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAOauthorized signature. (k) Related Information (1) Refer to Mandatory Continuing Airworthiness Information (MCAI) TCCA AD CF–2020–34, dated October 6, 2020, for related information. This MCAI may be found in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0312. (2) For more information about this AD, contact Aziz Ahmed, Aerospace Engineer, Airframe and Propulsion Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7329; fax 516–794–5531; email 9avs-nyaco-cos@faa.gov. (3) For service information identified in this AD, contact De Havilland Aircraft of Canada Limited, Q-Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416– 375–4000; fax 416–375–4539; email thd@ dehavilland.com; internet https:// PO 00000 Frm 00003 Fmt 4702 Sfmt 4702 20461 dehavilland.com. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. Issued on April 13, 2021. Gaetano A. Sciortino, Deputy Director for Strategic Initiatives, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021–07985 Filed 4–19–21; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2021–0309; Project Identifier MCAI–2020–00918–T] RIN 2120–AA64 Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, Inc.) Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for MHI RJ Aviation ULC Model CL–600– 2C10 (Regional Jet Series 700, 701 & 702), CL–600–2C11 (Regional Jet Series 550), CL–600–2D15 (Regional Jet Series 705), CL–600–2D24 (Regional Jet Series 900), and CL–600–2E25 (Regional Jet Series 1000) airplanes. This proposed AD was prompted by reports and a design review indicating that there could be possible corrosion on the main landing gear (MLG) outer cylinder at the interface with the gland nut on the shock strut installation and on the forward and aft trunnion pins in the MLG dressed shock strut assembly. This proposed AD would require detailed inspections for corrosion on the MLG outer cylinder assemblies, certain MLG dressed shock strut assemblies, and the MLG outer cylinder at the gland nut threads, thread relief groove, and chamfer; a detailed inspection for the presence of corrosion-inhibiting compound (CIC) on the MLG forward and aft trunnion pins and grease adapter assemblies; applicable corrective actions; application of primer, paint, and CIC as applicable; re-identification of certain part numbers; and marking of the MOD STATUS field of the nameplate of certain parts. The FAA is proposing this AD to address the unsafe condition on these products. SUMMARY: E:\FR\FM\20APP1.SGM 20APP1 20462 Federal Register / Vol. 86, No. 74 / Tuesday, April 20, 2021 / Proposed Rules The FAA must receive comments on this proposed AD by June 4, 2021. 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 https://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 Bombardier service information identified in this NPRM, contact MHI RJ Aviation ULC, 12655 Henri-Fabre Blvd., Mirabel, Que´bec J7N 1E1 Canada; Widebody Customer Response Center North America toll-free telephone +1– 844–272–2720 or direct-dial telephone +1–514–855–8500; fax +1–514–855– 8501; email thd.crj@mhirj.com; internet https://eservices.aero.bombardier.com. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. DATES: Examining the AD Docket You may examine the AD docket on the internet at https:// www.regulations.gov by searching for and locating Docket No. FAA–2021– 0309; 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 NPRM, any comments received, and other information. The street address for Docket Operations is listed above. FOR FURTHER INFORMATION CONTACT: Darren Gassetto, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7323; fax 516–794–5531; email 9-avs-nyaco-cos@faa.gov. SUPPLEMENTARY INFORMATION: Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under ADDRESSES. Include ‘‘Docket No. FAA–2021–0309; Project Identifier MCAI–2020–00918–T’’ at the beginning of your comments. The most helpful VerDate Sep<11>2014 16:17 Apr 19, 2021 Jkt 253001 comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend the proposal because of those comments. Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to https:// www.regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this proposed AD. Confidential Business Information CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this NPRM contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this NPRM, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as ‘‘PROPIN.’’ The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this NPRM. Submissions containing CBI should be sent to Darren Gassetto, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516– 228–7323; fax 516–794–5531; email 9-avs-nyaco-cos@faa.gov. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking. Background Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued TCCA AD CF– 2019–17R1, dated June 18, 2020 (referred to after this as the Mandatory Continuing Airworthiness Information, or ‘‘the MCAI’’), to correct an unsafe condition for MHI RJ Aviation ULC (type certificate previously held by Bombardier, Inc.) Model CL–600–2C10 (Regional Jet Series 700, 701 & 702) airplanes, Model CL–600–2C11 (Regional Jet Series 550) airplanes, Model CL–600–2D15 (Regional Jet PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 Series 705) airplanes, CL–600–2D24 (Regional Jet Series 900) airplanes, and Model CL–600–2E25 (Regional Jet Series 1000) airplanes. You may examine the MCAI in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0309. This proposed AD was prompted by reports and a design review indicating that there could be corrosion on the MLG outer cylinder assemblies and certain MLG dressed shock strut assemblies; primer was not correctly applied at the gland nut thread relief groove and chamfer areas on certain MLG outer cylinders during production; and CIC was inadvertently removed from certain MLG forward and aft trunnion pins and grease adapter assemblies during maintenance. The FAA is proposing this AD to address undetected corrosion on the MLG forward and aft trunnion pins, and the gland nut interface on certain MLG outer cylinders, which could result in an MLG collapse. See the MCAI for additional background information. Related Service Information Under 1 CFR Part 51 Bombardier has issued the following service information. • Service Bulletin 670BA–32–024, Revision C, dated February 11, 2015, which describes procedures for a detailed visual inspection of the MLG outer cylinder assemblies and dressed shock strut assemblies for corrosion of the outer cylinder gland nut thread interface and relief area, and corrective actions including repair and corrosion removal. • Service Bulletin 670BA–32–034, Revision B, dated December 21, 2018, which describes procedures for a detailed visual inspection of the inside diameter of the MLG trunnion pins for discrepancies including the condition of paint and CIC and evidence of corrosion, and corrective actions including replacement and rework of the trunnion pins as applicable. • Service Bulletin 670BA–32–039, dated February 29, 2012, which describes procedures for inspections of the inner diameter of the MLG forward and aft trunnion pins for discrepancies including corrosion and inadequate CIC, and corrective actions including application of CIC and replacement of corroded forward and aft trunnion pins with serviceable parts. • Service Bulletin 670BA–32–052, dated February 9, 2015, which describes procedures for a detailed visual inspection of the gland nut thread relief groove and chamfer surface for the condition of the protective coating and E:\FR\FM\20APP1.SGM 20APP1 Federal Register / Vol. 86, No. 74 / Tuesday, April 20, 2021 / Proposed Rules 20463 for discrepancies including evidence of corrosion or rework at the gland nut thread relief groove and chamfer surface of the MLG shock strut outer cylinder assemblies, and corrective actions including corrosion removal. 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. FAA’s bilateral agreement with the State of Design Authority, the FAA has been notified of the unsafe condition described in the MCAI and service information referenced above. The FAA is proposing this AD because the FAA evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop on other products of the same type design. ‘‘Differences Between this Proposed AD and the MCAI or Service Information.’’ FAA’s Determination This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to the Proposed Requirements of This NPRM This proposed AD would require accomplishing the actions specified in the service information described previously, except as discussed under Costs of Compliance Differences Between This Proposed AD and the MCAI or Service Information Although certain service information specifies to return damaged MLG trunnion pins to Goodrich Landing Gear, that action would not be required by this proposed AD. The FAA estimates that this proposed AD affects 562 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD: ESTIMATED COSTS FOR REQUIRED ACTIONS Labor cost Parts cost Cost per product Cost on U.S. operators Up to 100 work-hours × $85 per hour = Up to $8,500 ........................................ Up to $36,604 ....... Up to $45,104 ....... Up to $25,348,448. According to the manufacturer, some or all of the costs of this proposed AD may be covered under warranty, thereby reducing the cost impact on affected operators. The FAA does not control warranty coverage for affected operators. As a result, the FAA has included all known costs in our cost estimate. 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 The FAA determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 VerDate Sep<11>2014 16:17 Apr 19, 2021 Jkt 253001 responsibilities among the various levels of government. For the reasons discussed above, I certify this proposed regulation: (1) Is not a ‘‘significant regulatory action’’ under Executive Order 12866, (2) Would not affect intrastate aviation in Alaska, and (3) Would 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 Proposed Amendment (b) Affected ADs None. (c) Applicability This AD applies to the MHI RJ Aviation ULC (type certificate previously held by Bombardier, Inc.) airplanes, certificated in any category, specified in paragraphs (c)(1) through (3) of this AD. (1) Model CL–600–2C10 (Regional Jet Series 700, 701 & 702) and Model CL–600– 2C11 (Regional Jet Series 550) airplanes, serial numbers 10002 and subsequent. (2) Model CL–600–2D15 (Regional Jet Series 705) airplanes and CL–600–2D24 (Regional Jet Series 900) airplanes, serial numbers 15001 and subsequent. (3) Model CL–600–2E25 (Regional Jet Series 1000) airplanes, serial numbers 19001 and subsequent. Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows: (d) Subject PART 39—AIRWORTHINESS DIRECTIVES This AD was prompted by reports and a design review indicating that there could be corrosion on the main landing gear (MLG) outer cylinder assemblies at the interface with the gland nut on the shock strut installation and on the forward and aft trunnion pins in the MLG dressed shock strut assemblies; primer was not correctly applied at the gland nut thread relief groove and chamfer areas on certain MLG outer cylinders during production; and corrosion-inhibiting compound (CIC) could have inadvertently been removed from certain MLG forward and aft trunnion pins and grease adapter assemblies during maintenance. The FAA is issuing this AD to address undetected corrosion on the MLG forward and aft trunnion pins, and the gland nut interface on certain MLG outer cylinders, which could result in an MLG collapse. 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: ■ MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, Inc.): Docket No. FAA–2021–0309; Project Identifier MCAI–2020–00918–T. (a) Comments Due Date The FAA must receive comments on this airworthiness directive (AD) by June 4, 2021. PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 Air Transport Association (ATA) of America Code 32, Landing Gear. (e) Reason E:\FR\FM\20APP1.SGM 20APP1 20464 Federal Register / Vol. 86, No. 74 / Tuesday, April 20, 2021 / Proposed Rules (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Inspection and Application of Corrosion Protection for MLG Outer Cylinder Assemblies and Certain MLG Dressed Shock Strut Assemblies For airplanes identified in paragraphs (c)(1) and (2) of this AD with MLG outer cylinder assemblies and MLG dressed shock strut assemblies having part numbers and serial numbers specified in the effectivity tables in Section 1.A.(1) of Bombardier Service Bulletin 670BA–32–024, Revision C, dated February 11, 2015 (Bombardier Service Bulletin 670BA–32–024, Revision C): At the applicable time specified in paragraph (g)(1) or (2) of this AD, do a detailed visual inspection for corrosion and all other required actions specified in, and in accordance with, Section 2., Part A, of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–024, Revision C. (1) For MLG assemblies that have accumulated 12,500 total flight hours or less, and have been in service for 72 months or less from entry into service or the last overhaul date: Within 6,500 flight hours or 36 months, whichever comes first, after the effective date of this AD. (2) For MLG assemblies that have accumulated more than 12,500 total flight hours, or have been in service for more than 72 months from entry into service or the last overhaul date: Within 3,500 flight hours or 24 months, whichever occurs first, after the effective date of this AD. (h) Inspection of Certain Other MLG Dressed Shock Strut Assemblies and Corrective Action For airplanes identified in paragraphs (c)(1) and (2) of this AD, equipped with MLG dressed shock strut assemblies having part numbers (P/Ns) 49000–25 through 49000–46 and P/Ns 49050–15 through 49050–22, on which the MLG active dynamic seal has been replaced with the spare dynamic seal as specified in Bombardier CRJ700/705/900/ 1000 Aircraft Maintenance Manual (AMM), CSP B–001, Task 32–11–10–960–802, Revision 37, dated November 25, 2011, or earlier: At the applicable time specified in paragraph (h)(1) or (2) of this AD, do a detailed visual inspection of the MLG dressed shock strut assemblies for corrosion, and all applicable corrective actions, in accordance with Section 2., Part B, of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–024, Revision C. (1) For MLG assemblies that have accumulated 12,500 total flight hours or less, and have been in service for 72 months or less from entry into service or the last overhaul date: Within 6,500 flight hours or 36 months, whichever comes first, after the effective date of this AD. (2) For MLG assemblies that have accumulated more than 12,500 total flight hours, or have been in service for more than 72 months from entry into service or the last overhaul date: Within 3,500 flight hours or 24 months, whichever occurs first, after the effective date of this AD. VerDate Sep<11>2014 16:17 Apr 19, 2021 Jkt 253001 (i) Inspection of MLG Outer Cylinder at the Gland Nut threads, Thread Relief Groove, and Chamfer and Corrective Action For airplanes identified in paragraphs (c)(1) through (3) of this AD equipped with MLG outer cylinder assemblies having part numbers and serial numbers specified in Section 1.A., Effectivity, of Bombardier Service Bulletin 670BA–32–052, dated February 9, 2015: Within 6,500 flight hours or 36 months, whichever occurs first after the effective date of this AD: Do a detailed visual inspection, of the MLG shock strut outer cylinder assemblies and do all other required actions specified in, and, in accordance with Section 2. of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–052, dated February 9, 2015. (j) Inspection of Certain MLG Forward and Aft Trunnion Pins, and Corrective Action For airplanes identified in paragraphs (c)(1) through (3) of this AD equipped with MLG forward and aft trunnion pins and grease adapter assemblies having part numbers and serial numbers specified in Section 1.A., Effectivity, of Bombardier Service Bulletin 670BA–32–034, Revision B, dated December 21, 2018: At the applicable time specified in paragraph (j)(1) or (2) of this AD, do a detailed visual inspection of the MLG forward and aft trunnion pins and do all applicable corrective actions, in accordance with Section 2.B. and paragraphs 2.C.(6) and (8) of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–034, Revision B, dated December 21, 2018. Note 1 to paragraph (j): The corrective action is applicable only to MLG forward and aft trunnion pins having P/Ns 49101–9, –11, and –13 reworked from P/Ns 49101–1, –5, and –7, as specified in the procedures in Goodrich Service Bulletin 49101–32–47, any revision. The corrective action is not applicable to MLG forward and aft trunnion pins having P/Ns 49101–9, –11, and –13 that were installed as original equipment or purchased from Goodrich Landing Gear. (1) For MLG forward and aft trunnion pins and grease adapter assemblies that have not had the procedures specified in Goodrich Service Bulletin 49101–32–47, any revision, incorporated, at the applicable time specified in paragraph (j)(1)(i) or (ii) of this AD. (i) For MLG forward and aft trunnion pins that have accumulated 10,000 total flight hours or less, and have been in service 60 months or less from the entry into service or last overhaul date: Within 6,500 flight hours or 36 months, whichever occurs first, after the effective date of this AD. (ii) For MLG forward and aft trunnion pins that have accumulated more than 10,000 total flight hours, or have been in service for more than 60 months from entry into service or last overhaul date: Within 3,000 flight hours or 24 months, whichever occurs first, after the effective date of this AD. (2) For MLG forward and aft trunnion pins that have had the procedures specified in Goodrich Service Bulletin 49101–32–47, any revision, incorporated: Within 6,500 flight hours or 36 months, whichever occurs first, after the effective date of this AD. PO 00000 Frm 00006 Fmt 4702 Sfmt 4702 (k) Inspection of Certain Other MLG Trunnion Pins Having P/Ns 49101–9, 49101– 11, and 49101–13, Maintained Using Certain Maintenance Instructions For airplanes identified in paragraphs (c)(1) through (3) of this AD equipped with MLG forward and aft trunnion pins having P/Ns 49101–9, 49101–11, and 49101–13 that were maintained in accordance with the tasks identified in paragraphs (k)(1) through (4) of this AD: Within 6,500 flight hours or 36 months after the effective date of this AD, whichever occurs first, do a detailed visual inspection of the MLG forward and aft trunnion pins, and do all applicable corrective actions, in accordance with Section 2. of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–039, dated February 29, 2012. (1) Bombardier CRJ700/705/900/1000 AMM, CSP B–001, Task 32–11–05–400–801 A01, Revision 31, dated March 20, 2010, or earlier. (2) Bombardier CRJ700/705/900/1000 AMM, CSP B–001, Task 32–11–05–400–801 A02, Revision 34, dated November 20, 2010, or earlier. (3) Bombardier CRJ700/705/900/1000 AMM, CSP B–001, Task 32–11–05–400–804 A01, Revision 35, dated March 20, 2011, or earlier. (4) Bombardier CRJ700/705/900/1000 AMM, CSP B–001, Task 32–11–05–400–805 A01, Revision 35, dated March 20, 2011, or earlier. Note 2 to paragraph (k): The corrective action described in this paragraph is not applicable to MLG forward and aft trunnion pins having P/Ns 49101–9, –11, and –13 reworked from P/Ns 49101–1, –5, and –7 as specified in the procedures in Goodrich SB 49101–32–47, any revision. The corrective action described in this paragraph is applicable to MLG forward and aft trunnion pins having P/Ns 49101–9, –11, and –13 installed as original equipment or purchased from Goodrich Landing Gear. (l) Credit for Previous Actions (1) This paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Section 2., Part A, of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32– 024, Revision B, dated December 19, 2012. (2) This paragraph provides credit for actions required by paragraph (h) of this AD if those actions were performed before the effective date of this AD using Section 2., Part B, of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32– 024, Revision B, dated December 19, 2012; or Bombardier CRJ700/705/900/1000 Aircraft Maintenance Manual (AMM), CSP B–001, Task 32–11–10–960–802, Revision 38, dated March 25, 2012. (3) This paragraph provides credit for actions required by paragraph (j) of this AD if those actions were performed before the effective date of this AD using Section 2.B. and paragraphs 2.C.(6) and (8) of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–034, dated February 29, 2012; or Revision A, dated August 17, 2012. E:\FR\FM\20APP1.SGM 20APP1 Federal Register / Vol. 86, No. 74 / Tuesday, April 20, 2021 / Proposed Rules (4) This paragraph provides credit for actions required by paragraph (k) of this AD, if those actions were performed before the effective date of this AD using the service information specified in paragraphs (l)(4)(i) through (iv) of this AD. (i) Bombardier CRJ700/900/1000 Aircraft Maintenance Manual (AMM), CSP B–001, Task 32–11–05–400–801 A01, Revision 38, dated March 25, 2012. (ii) Bombardier CRJ700/900/1000 AMM, CSP B–001, Task 32–11–05–400–801 A02, Revision 38, dated March 25, 2012. (iii) Bombardier CRJ700/900/1000 AMM, CSP B–001, Task 32–11–05–400–804 A01, Revision 37, dated November 25, 2011, for actions specified in Section 2.B.(1) of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–039, dated February 29, 2012. (iv) Bombardier CRJ700/900/1000 AMM, CSP B–001, Task 32–11–05–400–805 A01, Revision 37, dated November 25, 2011, for actions specified in Section 2.B.(2) of the Accomplishment Instructions of Bombardier Service Bulletin 670BA–32–039, dated February 29, 2012. (m) No Requirement for Return of Parts Although certain service information referenced in this AD specifies to return damaged MLG trunnion pins to Goodrich Landing Gear, this AD does not include that requirement. (n) Other FAA AD Provisions The following provisions also apply to this AD: (1) Alternative Methods of Compliance (AMOCs): The Manager, New York 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 ATTN: Program Manager, Continuing Operational Safety, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7300; fax 516–794–5531. 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. (2) Contacting the Manufacturer: For any requirement in this AD to obtain instructions from a manufacturer, the instructions must be accomplished using a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada Civil Aviation (TCCA); or MHI RJ Aviation ULC’s TCCA Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature. (o) Related Information (1) Refer to Mandatory Continuing Airworthiness Information (MCAI) TCCA AD CF–2019–17R1, dated June 18, 2020, for related information. This MCAI may be found in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0309. VerDate Sep<11>2014 16:17 Apr 19, 2021 Jkt 253001 (2) For more information about this AD, contact Darren Gassetto, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228– 7323; fax 516–794–5531; email 9-avs-nyacocos@faa.gov. (3) For Bombardier service information identified in this AD, contact MHI RJ Aviation ULC, 12655 Henri-Fabre Blvd., Mirabel, Que´bec J7N 1E1 Canada; Widebody Customer Response Center North America toll-free telephone +1–844–272–2720 or direct-dial telephone +1–514–855–8500; fax +1–514–855–8501; email thd.crj@mhirj.com; internet https:// eservices.aero.bombardier.com. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. Issued on April 13, 2021. Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021–08053 Filed 4–19–21; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 20465 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 https://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. • 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 NPRM, contact GE Aviation Czech, Beranovy´ch 65 199 02 Praha 9— Letnˇany, Czech Republic; phone: +420 222 538 111. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call (781) 238–7759. ADDRESSES: 14 CFR Part 39 Examining the AD Docket [Docket No. FAA–2021–0316; Project Identifier MCAI–2020–00461–E] You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA–2021–0316; 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 NPRM, the mandatory continuing airworthiness information (MCAI), any comments received, and other information. The street address for Docket Operations is listed above. FOR FURTHER INFORMATION CONTACT: Barbara Caufield, Aviation Safety Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: (781) 238–7146; fax: (781) 238– 7199; email: barbara.caufield@faa.gov. SUPPLEMENTARY INFORMATION: RIN 2120–AA64 Airworthiness Directives; GE Aviation Czech s.r.o. (Type Certificate Previously Held by WALTER Engines a.s., Walter a.s., and MOTORLET a.s.) Turboprop Engines Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: The FAA proposes to adopt a new airworthiness directive (AD) for all GE Aviation Czech s.r.o. (GEAC) H75– 200, H80–100, and H80–200 model turboprop engines. This proposed AD was prompted by several reports of engine gas generator speed (Ng) rollbacks occurring below idle on GEAC H75–200, H80–100, and H80–200 model turboprop engines. This proposed AD would require an inspection of a certain part number (P/N) fuel control unit (FCU) and, if deficiencies are detected, replacement of the FCU with a part eligible for installation. The FAA is proposing this AD to address the unsafe condition on these products. DATES: The FAA must receive comments on this proposed AD by June 4, 2021. SUMMARY: PO 00000 Frm 00007 Fmt 4702 Sfmt 4702 Comments Invited The FAA invites you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under ADDRESSES. Include ‘‘Docket No. FAA–2021–0316; Project Identifier MCAI–2020–00461–E’’ at the beginning of your comments. The most helpful comments reference a specific portion of the proposal, explain the reason for any recommended change, and include supporting data. The FAA will consider E:\FR\FM\20APP1.SGM 20APP1

Agencies

[Federal Register Volume 86, Number 74 (Tuesday, April 20, 2021)]
[Proposed Rules]
[Pages 20461-20465]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-08053]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0309; Project Identifier MCAI-2020-00918-T]
RIN 2120-AA64


Airworthiness Directives; MHI RJ Aviation ULC (Type Certificate 
Previously Held by Bombardier, Inc.) Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for MHI RJ Aviation ULC Model CL-600-2C10 (Regional Jet Series 700, 701 
& 702), CL-600-2C11 (Regional Jet Series 550), CL-600-2D15 (Regional 
Jet Series 705), CL-600-2D24 (Regional Jet Series 900), and CL-600-2E25 
(Regional Jet Series 1000) airplanes. This proposed AD was prompted by 
reports and a design review indicating that there could be possible 
corrosion on the main landing gear (MLG) outer cylinder at the 
interface with the gland nut on the shock strut installation and on the 
forward and aft trunnion pins in the MLG dressed shock strut assembly. 
This proposed AD would require detailed inspections for corrosion on 
the MLG outer cylinder assemblies, certain MLG dressed shock strut 
assemblies, and the MLG outer cylinder at the gland nut threads, thread 
relief groove, and chamfer; a detailed inspection for the presence of 
corrosion-inhibiting compound (CIC) on the MLG forward and aft trunnion 
pins and grease adapter assemblies; applicable corrective actions; 
application of primer, paint, and CIC as applicable; re-identification 
of certain part numbers; and marking of the MOD STATUS field of the 
nameplate of certain parts. The FAA is proposing this AD to address the 
unsafe condition on these products.

[[Page 20462]]


DATES: The FAA must receive comments on this proposed AD by June 4, 
2021.

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 https://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 Bombardier service information identified in this NPRM, contact 
MHI RJ Aviation ULC, 12655 Henri-Fabre Blvd., Mirabel, Qu[eacute]bec 
J7N 1E1 Canada; Widebody Customer Response Center North America toll-
free telephone +1-844-272-2720 or direct-dial telephone +1-514-855-
8500; fax +1-514-855-8501; email [email protected]; internet https://eservices.aero.bombardier.com.
    You may view this service information at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 2200 South 216th St., Des 
Moines, WA. For information on the availability of this material at the 
FAA, call 206-231-3195.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-
0309; 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 NPRM, any comments received, and other information. The street 
address for Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Darren Gassetto, Aerospace Engineer, 
Mechanical Systems and Administrative Services Section, FAA, New York 
ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; 
telephone 516-228-7323; fax 516-794-5531; email [email protected].

SUPPLEMENTARY INFORMATION:

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under ADDRESSES. Include ``Docket No. FAA-2021-0309; Project Identifier 
MCAI-2020-00918-T'' at the beginning of your comments. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. The FAA 
will consider all comments received by the closing date and may amend 
the proposal because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this proposed AD.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this NPRM contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this NPRM, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this NPRM. Submissions containing CBI should be sent to 
Darren Gassetto, Aerospace Engineer, Mechanical Systems and 
Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart 
Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7323; fax 516-
794-5531; email [email protected]. Any commentary that the FAA 
receives which is not specifically designated as CBI will be placed in 
the public docket for this rulemaking.

Background

    Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued TCCA AD CF-2019-17R1, dated June 18, 
2020 (referred to after this as the Mandatory Continuing Airworthiness 
Information, or ``the MCAI''), to correct an unsafe condition for MHI 
RJ Aviation ULC (type certificate previously held by Bombardier, Inc.) 
Model CL-600-2C10 (Regional Jet Series 700, 701 & 702) airplanes, Model 
CL-600-2C11 (Regional Jet Series 550) airplanes, Model CL-600-2D15 
(Regional Jet Series 705) airplanes, CL-600-2D24 (Regional Jet Series 
900) airplanes, and Model CL-600-2E25 (Regional Jet Series 1000) 
airplanes. You may examine the MCAI in the AD docket on the internet at 
https://www.regulations.gov by searching for and locating Docket No. 
FAA-2021-0309.
    This proposed AD was prompted by reports and a design review 
indicating that there could be corrosion on the MLG outer cylinder 
assemblies and certain MLG dressed shock strut assemblies; primer was 
not correctly applied at the gland nut thread relief groove and chamfer 
areas on certain MLG outer cylinders during production; and CIC was 
inadvertently removed from certain MLG forward and aft trunnion pins 
and grease adapter assemblies during maintenance. The FAA is proposing 
this AD to address undetected corrosion on the MLG forward and aft 
trunnion pins, and the gland nut interface on certain MLG outer 
cylinders, which could result in an MLG collapse. See the MCAI for 
additional background information.

Related Service Information Under 1 CFR Part 51

    Bombardier has issued the following service information.
     Service Bulletin 670BA-32-024, Revision C, dated February 
11, 2015, which describes procedures for a detailed visual inspection 
of the MLG outer cylinder assemblies and dressed shock strut assemblies 
for corrosion of the outer cylinder gland nut thread interface and 
relief area, and corrective actions including repair and corrosion 
removal.
     Service Bulletin 670BA-32-034, Revision B, dated December 
21, 2018, which describes procedures for a detailed visual inspection 
of the inside diameter of the MLG trunnion pins for discrepancies 
including the condition of paint and CIC and evidence of corrosion, and 
corrective actions including replacement and rework of the trunnion 
pins as applicable.
     Service Bulletin 670BA-32-039, dated February 29, 2012, 
which describes procedures for inspections of the inner diameter of the 
MLG forward and aft trunnion pins for discrepancies including corrosion 
and inadequate CIC, and corrective actions including application of CIC 
and replacement of corroded forward and aft trunnion pins with 
serviceable parts.
     Service Bulletin 670BA-32-052, dated February 9, 2015, 
which describes procedures for a detailed visual inspection of the 
gland nut thread relief groove and chamfer surface for the condition of 
the protective coating and

[[Page 20463]]

for discrepancies including evidence of corrosion or rework at the 
gland nut thread relief groove and chamfer surface of the MLG shock 
strut outer cylinder assemblies, and corrective actions including 
corrosion removal.
    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.

FAA's Determination

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to the FAA's bilateral agreement with the State of Design Authority, 
the FAA has been notified of the unsafe condition described in the MCAI 
and service information referenced above. The FAA is proposing this AD 
because the FAA evaluated all the relevant information and determined 
the unsafe condition described previously is likely to exist or develop 
on other products of the same type design.

Proposed Requirements of This NPRM

    This proposed AD would require accomplishing the actions specified 
in the service information described previously, except as discussed 
under ``Differences Between this Proposed AD and the MCAI or Service 
Information.''

Differences Between This Proposed AD and the MCAI or Service 
Information

    Although certain service information specifies to return damaged 
MLG trunnion pins to Goodrich Landing Gear, that action would not be 
required by this proposed AD.

Costs of Compliance

    The FAA estimates that this proposed AD affects 562 airplanes of 
U.S. registry. The FAA estimates the following costs to comply with 
this proposed AD:

                                      Estimated Costs for Required Actions
----------------------------------------------------------------------------------------------------------------
              Labor cost                      Parts cost            Cost per product      Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Up to 100 work-hours x $85 per hour =  Up to $36,604..........  Up to $45,104..........  Up to $25,348,448.
 Up to $8,500.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some or all of the costs of this 
proposed AD may be covered under warranty, thereby reducing the cost 
impact on affected operators. The FAA does not control warranty 
coverage for affected operators. As a result, the FAA has included all 
known costs in our cost estimate.

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

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Would not affect intrastate aviation in Alaska, and
    (3) Would 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 Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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:

MHI RJ Aviation ULC (Type Certificate Previously Held by Bombardier, 
Inc.): Docket No. FAA-2021-0309; Project Identifier MCAI-2020-00918-
T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by June 4, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to the MHI RJ Aviation ULC (type certificate 
previously held by Bombardier, Inc.) airplanes, certificated in any 
category, specified in paragraphs (c)(1) through (3) of this AD.
    (1) Model CL-600-2C10 (Regional Jet Series 700, 701 & 702) and 
Model CL-600-2C11 (Regional Jet Series 550) airplanes, serial 
numbers 10002 and subsequent.
    (2) Model CL-600-2D15 (Regional Jet Series 705) airplanes and 
CL-600-2D24 (Regional Jet Series 900) airplanes, serial numbers 
15001 and subsequent.
    (3) Model CL-600-2E25 (Regional Jet Series 1000) airplanes, 
serial numbers 19001 and subsequent.

(d) Subject

    Air Transport Association (ATA) of America Code 32, Landing 
Gear.

(e) Reason

    This AD was prompted by reports and a design review indicating 
that there could be corrosion on the main landing gear (MLG) outer 
cylinder assemblies at the interface with the gland nut on the shock 
strut installation and on the forward and aft trunnion pins in the 
MLG dressed shock strut assemblies; primer was not correctly applied 
at the gland nut thread relief groove and chamfer areas on certain 
MLG outer cylinders during production; and corrosion-inhibiting 
compound (CIC) could have inadvertently been removed from certain 
MLG forward and aft trunnion pins and grease adapter assemblies 
during maintenance. The FAA is issuing this AD to address undetected 
corrosion on the MLG forward and aft trunnion pins, and the gland 
nut interface on certain MLG outer cylinders, which could result in 
an MLG collapse.

[[Page 20464]]

(f) Compliance

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

(g) Inspection and Application of Corrosion Protection for MLG Outer 
Cylinder Assemblies and Certain MLG Dressed Shock Strut Assemblies

    For airplanes identified in paragraphs (c)(1) and (2) of this AD 
with MLG outer cylinder assemblies and MLG dressed shock strut 
assemblies having part numbers and serial numbers specified in the 
effectivity tables in Section 1.A.(1) of Bombardier Service Bulletin 
670BA-32-024, Revision C, dated February 11, 2015 (Bombardier 
Service Bulletin 670BA-32-024, Revision C): At the applicable time 
specified in paragraph (g)(1) or (2) of this AD, do a detailed 
visual inspection for corrosion and all other required actions 
specified in, and in accordance with, Section 2., Part A, of the 
Accomplishment Instructions of Bombardier Service Bulletin 670BA-32-
024, Revision C.
    (1) For MLG assemblies that have accumulated 12,500 total flight 
hours or less, and have been in service for 72 months or less from 
entry into service or the last overhaul date: Within 6,500 flight 
hours or 36 months, whichever comes first, after the effective date 
of this AD.
    (2) For MLG assemblies that have accumulated more than 12,500 
total flight hours, or have been in service for more than 72 months 
from entry into service or the last overhaul date: Within 3,500 
flight hours or 24 months, whichever occurs first, after the 
effective date of this AD.

(h) Inspection of Certain Other MLG Dressed Shock Strut Assemblies and 
Corrective Action

    For airplanes identified in paragraphs (c)(1) and (2) of this 
AD, equipped with MLG dressed shock strut assemblies having part 
numbers (P/Ns) 49000-25 through 49000-46 and P/Ns 49050-15 through 
49050-22, on which the MLG active dynamic seal has been replaced 
with the spare dynamic seal as specified in Bombardier CRJ700/705/
900/1000 Aircraft Maintenance Manual (AMM), CSP B-001, Task 32-11-
10-960-802, Revision 37, dated November 25, 2011, or earlier: At the 
applicable time specified in paragraph (h)(1) or (2) of this AD, do 
a detailed visual inspection of the MLG dressed shock strut 
assemblies for corrosion, and all applicable corrective actions, in 
accordance with Section 2., Part B, of the Accomplishment 
Instructions of Bombardier Service Bulletin 670BA-32-024, Revision 
C.
    (1) For MLG assemblies that have accumulated 12,500 total flight 
hours or less, and have been in service for 72 months or less from 
entry into service or the last overhaul date: Within 6,500 flight 
hours or 36 months, whichever comes first, after the effective date 
of this AD.
    (2) For MLG assemblies that have accumulated more than 12,500 
total flight hours, or have been in service for more than 72 months 
from entry into service or the last overhaul date: Within 3,500 
flight hours or 24 months, whichever occurs first, after the 
effective date of this AD.

(i) Inspection of MLG Outer Cylinder at the Gland Nut threads, Thread 
Relief Groove, and Chamfer and Corrective Action

    For airplanes identified in paragraphs (c)(1) through (3) of 
this AD equipped with MLG outer cylinder assemblies having part 
numbers and serial numbers specified in Section 1.A., Effectivity, 
of Bombardier Service Bulletin 670BA-32-052, dated February 9, 2015: 
Within 6,500 flight hours or 36 months, whichever occurs first after 
the effective date of this AD: Do a detailed visual inspection, of 
the MLG shock strut outer cylinder assemblies and do all other 
required actions specified in, and, in accordance with Section 2. of 
the Accomplishment Instructions of Bombardier Service Bulletin 
670BA-32-052, dated February 9, 2015.

(j) Inspection of Certain MLG Forward and Aft Trunnion Pins, and 
Corrective Action

    For airplanes identified in paragraphs (c)(1) through (3) of 
this AD equipped with MLG forward and aft trunnion pins and grease 
adapter assemblies having part numbers and serial numbers specified 
in Section 1.A., Effectivity, of Bombardier Service Bulletin 670BA-
32-034, Revision B, dated December 21, 2018: At the applicable time 
specified in paragraph (j)(1) or (2) of this AD, do a detailed 
visual inspection of the MLG forward and aft trunnion pins and do 
all applicable corrective actions, in accordance with Section 2.B. 
and paragraphs 2.C.(6) and (8) of the Accomplishment Instructions of 
Bombardier Service Bulletin 670BA-32-034, Revision B, dated December 
21, 2018.

    Note 1 to paragraph (j): The corrective action is applicable 
only to MLG forward and aft trunnion pins having P/Ns 49101-9, -11, 
and -13 reworked from P/Ns 49101-1, -5, and -7, as specified in the 
procedures in Goodrich Service Bulletin 49101-32-47, any revision. 
The corrective action is not applicable to MLG forward and aft 
trunnion pins having P/Ns 49101-9, -11, and -13 that were installed 
as original equipment or purchased from Goodrich Landing Gear.

    (1) For MLG forward and aft trunnion pins and grease adapter 
assemblies that have not had the procedures specified in Goodrich 
Service Bulletin 49101-32-47, any revision, incorporated, at the 
applicable time specified in paragraph (j)(1)(i) or (ii) of this AD.
    (i) For MLG forward and aft trunnion pins that have accumulated 
10,000 total flight hours or less, and have been in service 60 
months or less from the entry into service or last overhaul date: 
Within 6,500 flight hours or 36 months, whichever occurs first, 
after the effective date of this AD.
    (ii) For MLG forward and aft trunnion pins that have accumulated 
more than 10,000 total flight hours, or have been in service for 
more than 60 months from entry into service or last overhaul date: 
Within 3,000 flight hours or 24 months, whichever occurs first, 
after the effective date of this AD.
    (2) For MLG forward and aft trunnion pins that have had the 
procedures specified in Goodrich Service Bulletin 49101-32-47, any 
revision, incorporated: Within 6,500 flight hours or 36 months, 
whichever occurs first, after the effective date of this AD.

(k) Inspection of Certain Other MLG Trunnion Pins Having P/Ns 49101-9, 
49101-11, and 49101-13, Maintained Using Certain Maintenance 
Instructions

    For airplanes identified in paragraphs (c)(1) through (3) of 
this AD equipped with MLG forward and aft trunnion pins having P/Ns 
49101-9, 49101-11, and 49101-13 that were maintained in accordance 
with the tasks identified in paragraphs (k)(1) through (4) of this 
AD: Within 6,500 flight hours or 36 months after the effective date 
of this AD, whichever occurs first, do a detailed visual inspection 
of the MLG forward and aft trunnion pins, and do all applicable 
corrective actions, in accordance with Section 2. of the 
Accomplishment Instructions of Bombardier Service Bulletin 670BA-32-
039, dated February 29, 2012.
    (1) Bombardier CRJ700/705/900/1000 AMM, CSP B-001, Task 32-11-
05-400-801 A01, Revision 31, dated March 20, 2010, or earlier.
    (2) Bombardier CRJ700/705/900/1000 AMM, CSP B-001, Task 32-11-
05-400-801 A02, Revision 34, dated November 20, 2010, or earlier.
    (3) Bombardier CRJ700/705/900/1000 AMM, CSP B-001, Task 32-11-
05-400-804 A01, Revision 35, dated March 20, 2011, or earlier.
    (4) Bombardier CRJ700/705/900/1000 AMM, CSP B-001, Task 32-11-
05-400-805 A01, Revision 35, dated March 20, 2011, or earlier.

    Note 2 to paragraph (k): The corrective action described in this 
paragraph is not applicable to MLG forward and aft trunnion pins 
having P/Ns 49101-9, -11, and -13 reworked from P/Ns 49101-1, -5, 
and -7 as specified in the procedures in Goodrich SB 49101-32-47, 
any revision. The corrective action described in this paragraph is 
applicable to MLG forward and aft trunnion pins having P/Ns 49101-9, 
-11, and -13 installed as original equipment or purchased from 
Goodrich Landing Gear.

(l) Credit for Previous Actions

    (1) This paragraph provides credit for actions required by 
paragraph (g) of this AD, if those actions were performed before the 
effective date of this AD using Section 2., Part A, of the 
Accomplishment Instructions of Bombardier Service Bulletin 670BA-32-
024, Revision B, dated December 19, 2012.
    (2) This paragraph provides credit for actions required by 
paragraph (h) of this AD if those actions were performed before the 
effective date of this AD using Section 2., Part B, of the 
Accomplishment Instructions of Bombardier Service Bulletin 670BA-32-
024, Revision B, dated December 19, 2012; or Bombardier CRJ700/705/
900/1000 Aircraft Maintenance Manual (AMM), CSP B-001, Task 32-11-
10-960-802, Revision 38, dated March 25, 2012.
    (3) This paragraph provides credit for actions required by 
paragraph (j) of this AD if those actions were performed before the 
effective date of this AD using Section 2.B. and paragraphs 2.C.(6) 
and (8) of the Accomplishment Instructions of Bombardier Service 
Bulletin 670BA-32-034, dated February 29, 2012; or Revision A, dated 
August 17, 2012.

[[Page 20465]]

    (4) This paragraph provides credit for actions required by 
paragraph (k) of this AD, if those actions were performed before the 
effective date of this AD using the service information specified in 
paragraphs (l)(4)(i) through (iv) of this AD.
    (i) Bombardier CRJ700/900/1000 Aircraft Maintenance Manual 
(AMM), CSP B-001, Task 32-11-05-400-801 A01, Revision 38, dated 
March 25, 2012.
    (ii) Bombardier CRJ700/900/1000 AMM, CSP B-001, Task 32-11-05-
400-801 A02, Revision 38, dated March 25, 2012.
    (iii) Bombardier CRJ700/900/1000 AMM, CSP B-001, Task 32-11-05-
400-804 A01, Revision 37, dated November 25, 2011, for actions 
specified in Section 2.B.(1) of the Accomplishment Instructions of 
Bombardier Service Bulletin 670BA-32-039, dated February 29, 2012.
    (iv) Bombardier CRJ700/900/1000 AMM, CSP B-001, Task 32-11-05-
400-805 A01, Revision 37, dated November 25, 2011, for actions 
specified in Section 2.B.(2) of the Accomplishment Instructions of 
Bombardier Service Bulletin 670BA-32-039, dated February 29, 2012.

(m) No Requirement for Return of Parts

    Although certain service information referenced in this AD 
specifies to return damaged MLG trunnion pins to Goodrich Landing 
Gear, this AD does not include that requirement.

(n) Other FAA AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New 
York 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 ATTN: Program Manager, Continuing Operational 
Safety, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; telephone 516-228-7300; fax 516-794-5531. 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.
    (2) Contacting the Manufacturer: For any requirement in this AD 
to obtain instructions from a manufacturer, the instructions must be 
accomplished using a method approved by the Manager, New York ACO 
Branch, FAA; or Transport Canada Civil Aviation (TCCA); or MHI RJ 
Aviation ULC's TCCA Design Approval Organization (DAO). If approved 
by the DAO, the approval must include the DAO-authorized signature.

(o) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) TCCA AD CF-2019-17R1, dated June 18, 2020, for related 
information. This MCAI may be found in the AD docket on the internet 
at https://www.regulations.gov by searching for and locating Docket 
No. FAA-2021-0309.
    (2) For more information about this AD, contact Darren Gassetto, 
Aerospace Engineer, Mechanical Systems and Administrative Services 
Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, 
Westbury, NY 11590; telephone 516-228-7323; fax 516-794-5531; email 
[email protected].
    (3) For Bombardier service information identified in this AD, 
contact MHI RJ Aviation ULC, 12655 Henri-Fabre Blvd., Mirabel, 
Qu[eacute]bec J7N 1E1 Canada; Widebody Customer Response Center 
North America toll-free telephone +1-844-272-2720 or direct-dial 
telephone +1-514-855-8500; fax +1-514-855-8501; email 
[email protected]; internet https://eservices.aero.bombardier.com. 
You may view this service information at the FAA, Airworthiness 
Products Section, Operational Safety Branch, 2200 South 216th St., 
Des Moines, WA. For information on the availability of this material 
at the FAA, call 206-231-3195.

    Issued on April 13, 2021.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2021-08053 Filed 4-19-21; 8:45 am]
BILLING CODE 4910-13-P