2021-23-11: Powerplant System

1. The authority citation for part 39 continues to read as follows: Authority: 49 U.S.C. 106(g), 40113, 44701. 2. The FAA amends § 39.13 by adding the following new airworthiness directive: 2021-23-11 Learjet Inc.: Amendment 39-21809; Docket No. FAA-2021-0660; Project Identifier AD-2021-00398-T. (a) Effective Date This airworthiness directive (AD) is effective January 10, 2022. (b) Affected ADs None. (c) Applicability This AD applies to Learjet Inc. Model 45 (Learjet 40), Model 45 (Learjet 45), Model 45 (Learjet 70), and Model 45 (Learjet 75) airplanes, serial numbers 45-002 through 45-556 and 45-2001 through 45-2146, certificated in any category. (d) Subject Joint Aircraft System Component (JASC) Code 7100, Powerplant System. (e) Unsafe Condition This AD was prompted by a report of a fuel leak due to a cracked fuel line between the engine fuel control and the engine fuel flow meter. The FAA is issuing this AD to prevent cracking and failures. The unsafe condition, if not addressed, could result in an engine installation fire, which could progress to an uncontrolled fire and consequent loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Reporting Requirement Within 60 days after the effective date of this AD, report the following information, where available, to the Wichita ACO Branch via email at thomas.teplik@faa.gov and Wichita-COS@faa.gov; or by mail to Wichita ACO Branch, FAA, Attn: Thomas Teplik, 1801 S. Airport Road, Room 100, Wichita, KS 67209. (1) Name of the owner; the address of the owner; name of the organization doing the actions required by this AD; the date the actions were completed; the name of the person submitting the report; the address, telephone number, and email of the person submitting the report. (2) The fan vibration levels that have been recorded in the airplane and engine maintenance records since November 1, 2019. Include the airplane and engine serial numbers. (3) The date of each vibration level recorded and the associated hours time-in-service (TIS) for the airplane and each engine. (4) For each fan vibration level reported, include: (i) Whether molybdenum coating for the fan was applied per Temporary Revision 72-494, dated August 15, 2017 (or as subsequently incorporated into the engine's Inspection/Repair Manual TFE731 (ATA Number 72-IR-02)). (ii) If molybdenum coating was applied using a different process than Temporary Revision 72-494, dated August 15, 2017 (or as subsequently incorporated into the engine's Inspection/Repair Manual TFE731 (ATA Number 72-IR-02)), report the process by which the molybdenum coating was applied and the revision level of the document defining the application process for the molybdenum coating. Note 1 to paragraph (g)(4): Temporary Revision 72-494, dated August 15, 2017, specifies applying a dry film lubricant on the mating surfaces of the fan hub and the fan blades. The lubricating solid for this dry film lubricant is molybdenum disulfide, which is referred to in this AD as molybdenum coating. (5) For each fan vibration level reported, the fan hub serial number and hours TIS for this fan hub. (6) Installation date and service bulletin (SB) revision level for the installation of the bracket assembly with fuel flow meter and hose if installed before the effective date of this AD. (7) Any failures of the bracket assembly with fuel flow meter and hose installed in accordance with any SB listed in paragraph (h) of this AD or any prior revision of these SBs. (8) Installation date and SB revision level used for installation of the fuel control screws within the engine fuel control in accordance with Honeywell SB TFE731-73-5146. (9) Any failures of fuel control screws after compliance with Honeywell SB TFE731-73-5146. (h) Replacement Within 12 months after the effective date of this AD or 750 hours TIS after the effective date of this AD, whichever occurs first, replace the engine fuel flow meter bracket in accordance with the Accomplishment Instructions, paragraphs 3.A through 3.C, of the following Bombardier SB, listed in paragraphs (h)(1) through (4) of this AD, applicable to your airplane model configuration. (1) Bombardier Learjet 40 SB 40-73-01, Revision 1, dated January 9, 2017. (2) Bombardier Learjet 45 SB 45-73-2 Revision 1, dated January 9, 2017. (3) Bombardier Learjet 70 SB 70-73-01 Revision 1, dated January 9, 2017. (4) Bombardier Learjet 75 SB 75-73-01, Revision 2, dated January 9, 2017. (i) Credit for Previous Actions (1) This paragraph provides credit for the action required by paragraph (h) of this AD, if that action was performed before the effective date of this AD using Bombardier Learjet 40 SB 40-73-01, Basic Issue; Bombardier Learjet 45 Service Bulletin SB 45-73-2, Basic Issue; Bombardier Learjet 70 SB 70-73-01, Basic Issue; or Bombardier Learjet 75 SB 75-73-01, Basic Issue; all dated October 3, 2016; or Bombardier Learjet 75 SB 75-73-01, Revision 1, dated October 10, 2016. (2) To take credit for any previous action, you must comply with paragraph (g) of this AD within 60 days after the effective date of this AD. (j) Alternative Methods of Compliance (AMOCs) (1) The Manager, Wichita 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 (k) 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. (k) Related Information For more information about this AD, contact Thomas Teplik, Aviation Safety Engineer, Wichita ACO Branch, FAA, 1801 S. Airport Road, Wichita, KS 67209; phone: (316) 946-4196; email: thomas.teplik@faa.gov. (l) 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) Bombardier Learjet 40 Service Bulletin 40-73-01, Revision 1, dated January 9, 2017. (ii) Bombardier Learjet 45 Service Bulletin 45-73-2 Revision 1, dated January 9, 2017. (iii) Bombardier Learjet 70 Service Bulletin 70-73-01 Revision 1, dated January 9, 2017. (iv) Bombardier Learjet 75 Service Bulletin 75-73-01, Revision 2, dated January 9, 2017. (3) For service information identified in this AD, contact Learjet Inc., One Learjet Way, Wichita, KS 67209; phone: (316) 946-2000; email: ac.ict@aero.bombardier.com; website: https://businessaircraft.bombardier.com/en/aircraft/Learjet.html. (4) 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 (816) 329-4148. (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: https://www.archives.gov/federal-register/cfr/ibr-locations.html. Issued on November 1, 2021. Lance T. Gant, Director, Compliance & Airworthiness Division, Aircraft Certification Service. [FR Doc. 2021-26331 Filed 12-3-21; 8:45 am]BILLING CODE 4910-13-P