AD 2021-18-10

The FAA is adopting a new airworthiness directive (AD) for certain Bell Textron Canada Limited Model 429 helicopters. This AD was prompted by three reports of unexpected forces or uncommanded inputs to the directional (yaw) control system. This AD requires revising the existing Rotorcraft Flight \n\n((Page 49910)) \n\nManual (RFM) for your helicopter. The FAA is issuing this AD to address the unsafe condition on these products.

Final rule.

The Amendment \n\n\n\tAccordingly, under the authority delegated to me by the Administrator, \n\n((Page 49911)) \n\nthe FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n0 1. The authority citation for part 39 continues to read as follows: \n\n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n\n\nSec. 39.13 (Amended) \n\n0 2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive: \n\n2021-18-10 Bell Textron Canada Limited: Amendment 39-21711; Docket No. FAA-2021-0497; Project Identifier 2019-SW-043-AD. \n\n(a) Effective Date \n\n\n\tThis airworthiness directive (AD) is effective October 12, 2021. \n\n(b) Affected ADs \n\n\n\tNone. \n\n(c) Applicability \n\n\n\tThis AD applies to Bell Textron Canada Limited Model 429 helicopters, certificated in any category, serial numbers 57001 and subsequent. \n\n(d) Subject \n\n\n\tJoint Aircraft Service Component (JASC) Code: 6720, Tail Rotor Control System. \n\n(e) Unsafe Condition \n\n\n\tThis AD was prompted by three reports of unexpected forces or uncommanded inputs to the directional (yaw) control system. The FAA is issuing this AD to prevent yaw trim runaway. The unsafe condition, if not addressed, could result in loss of control of the helicopter. \n\n(f) Compliance \n\n\n\tComply with this AD within the compliance times specified, unless already done. \n\n(g) Required Actions \n\n\n\t(1) Within 30 days after the effective date of this AD, revise the existing Rotorcraft Flight Manual for your helicopter as follows: \n\t(i) In Section 2, Normal Procedures, under 2-4. INTERIOR AND PRESTART CHECK, add the following as item 25: ''25. Depress the cyclic force TRIM REL button and collective FORCE REL button (4-axis only) to center actuators and extinguish any active out of detent indications.'' \n\t(ii) In Section 2, Normal Procedures, under 2-5. ENGINE START and under 2-8. TAKEOFF, add the following above item 1: ''CAUTION: WHEN MANIPULATING FLIGHT CONTROLS WITH FORCE TRIM SELECTED ON, DO NOT RELEASE AFFECTED FLIGHT CONTROL UNTIL THE OUT OF DETENT INDICATION EXTINGUISHES. THE FLIGHT CONTROLS MAY BE RESET BY DEPRESSING THE CYCLIC FORCE TRIM REL BUTTON AND COLLECTIVE FORCE REL BUTTON (4-AXIS ONLY) UNTIL THE OUT OF DETENT INDICATION EXTINGUISHES.'' \n\t(iii) In Section 3, Emergency and Malfunction Procedures, under 3-9. AUTOMATIC FLIGHT CONTROL SYSTEM, add the information in Figure 1 to paragraph (g)(1)(iii) of this AD as item 3-9-D: (GRAPHIC) (TIFF OMITTED) TR07SE21.000 \n\n\n\t(iv) In Section 4, Performance, under 4-2. POWER ASSURANCE CHECK, add the following above the instructions for performing a power assurance check: ''CAUTION: WHEN MANIPULATING FLIGHT CONTROLS WITH FORCE TRIM SELECTED ON, DO NOT RELEASE AFFECTED FLIGHT CONTROL UNTIL THE OUT OF DETENT INDICATION EXTINGUISHES. THE FLIGHT CONTROLS MAY BE RESET BY DEPRESSING THE CYCLIC FORCE TRIM REL BUTTON AND COLLECTIVE FORCE REL BUTTON (4-AXIS ONLY) UNTIL THE OUT OF DETENT INDICATION EXTINGUISHES.'' \n\t(2) Using a document with information identical to the information in paragraph (g)(1) of this AD is acceptable for compliance \n\n((Page 49912)) \n\nwith the actions required by paragraph (g)(1) of this AD. \n\t(3) The actions required by paragraphs (g)(1) and (2) of this AD may be performed by the owner/operator (pilot) holding at least a private pilot certificate and must be entered into the aircraft records showing compliance with this AD in accordance with Sec. 43.9(a)(1) through (4) and Sec. 91.417(a)(2)(v). The record must be maintained as required by Sec. 91.417, Sec. 121.380, or Sec. 135.439. \n\n(h) Alternative Methods of Compliance (AMOCs) \n\n\n\t(1) The Manager, International Validation 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 International Validation Branch, send it to the attention of the person identified in paragraph (i)(1) of this AD. Information may be emailed to: 9-AVS-AIR-730-AMOC@faa.gov. \n\t(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. \n\n(i) Related Information \n\n\n\t(1) For more information about this AD, contact Mitch Soth, Flight Test Engineer, Southwest Section, Flight Test Branch, Compliance & Airworthiness Division, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone (817) 222-5110; email mitch.soth@faa.gov. \n\t(2) The subject of this AD is addressed in Transport Canada Emergency AD CF-2019-16, dated May 6, 2019. You may view the Transport Canada AD on the internet at https://www.regulations.gov in Docket No. FAA-2021-0497. \n\n(j) Material Incorporated by Reference \n\n\n\tNone. \n\n\n\tIssued on August 26, 2021. Gaetano A. Sciortino, Deputy Director for Strategic Initiatives, Compliance & Airworthiness Division, Aircraft Certification Service. (FR Doc. 2021-19049 Filed 9-3-21; 8:45 am) BILLING CODE 4910-13-P

Background \n\n\n\tThe FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to Bell Textron Canada Limited Model 429 helicopters, serial numbers 57001 and subsequent. The NPRM published in the Federal Register on July 7, 2021 (86 FR 35692). In the NPRM, the FAA proposed to require revising the existing RFM for your helicopter by adding procedures in Section 2, Normal Procedures, under 2-4. INTERIOR AND PRESTART CHECK, 2-5. ENGINE START, and 2-8. TAKEOFF; Section 3, Emergency and Malfunction Procedures, under 3-9. AUTOMATIC FLIGHT CONTROL SYSTEM; and Section 4, Performance, under 4-2. POWER ASSURANCE CHECK. The owner/operator (pilot) may revise the existing RFM for your helicopter, and the owner/operator must enter compliance with the applicable paragraphs of the AD into the aircraft records in accordance with Sec. 43.9(a)(1) through (4) and Sec. 91.417(a)(2)(v). This is an exception to the FAA's standard maintenance regulations. \n\tThe NPRM was prompted by Transport Canada Emergency AD CF-2019-16, dated May 6, 2019 (Transport Canada AD CF-2019-16), issued by Transport Canada, which is the aviation authority for Canada to correct an unsafe condition for Bell Helicopter Textron Canada Limited (now Bell Textron Canada Limited) Model 429 helicopters, serial numbers 57001 and subsequent. Transport Canada advises of three reports of unexpected forces or uncommanded inputs to the directional (yaw) control system during ground operations. Investigation revealed that a yaw trim runaway can occur while the automatic pedal trim function is operating. This condition, if not addressed, could result in loss of control of the helicopter. Accordingly, Transport Canada AD CF-2019-16 requires revising Bell RFM BHT-429-FM-1 by incorporating revision 14, dated April 18, 2019. \n\nDiscussion of Final Airworthiness Directive \n\nComments \n\n\n\tThe FAA received one comment from an individual who supported the NPRM without change. \n\nConclusion \n\n\n\tThese helicopters have been approved by the aviation authority of Canada and are approved for operation in the United States. Pursuant to the FAA's bilateral agreement with Canada, Transport Canada, its technical representative, has notified the FAA of the unsafe condition described in its AD. The FAA reviewed the relevant data, considered the comment 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 helicopters. \n\nRelated Service Information \n\n\n\tThe FAA reviewed Section 2--Normal Procedures, Section 3--Emergency and Malfunction Procedures, and Section 4--Performance, of Bell RFM BHT-429-FM-1, Revision 14, dated April 18, 2019. This revision of the service information adds a procedure to reduce the risk of trim runaway during start sequence, cautions to reduce the risk of uncommanded control movement during engine start andtakeoff and re-setting force trim detent instructions during engine start and takeoff, and an emergency procedure to assist flight crew to recognize trim runaway and response instructions. \n\nCosts of Compliance \n\n\n\tThe FAA estimates that this AD affects 120 helicopters of U.S. Registry. Labor rates are estimated at $85 per work-hour. Based on these numbers, the FAA estimates the following costs to comply with this AD. \n\tRevising the existing RFM for your helicopter takes about 0.50 work-hour for an estimated cost of $43 per helicopter and $5,160 for the U.S. fleet. \n\nAuthority for This Rulemaking \n\n\n\tTitle 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. \n\tThe FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on helicopters identified in this rulemaking action. \n\nRegulatory Findings \n\n\n\tThis AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. \n\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, \n\t(2) Will not affect intrastate aviation in Alaska, and \n\t(3) Will not havea significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.