89 FR 162 pgs. 67577-67580 - Airworthiness Directives; Bombardier, Inc., Airplanes
Type: PRORULEVolume: 89Number: 162Pages: 67577 - 67580
Pages: 67577, 67578, 67579, 67580Docket number: [Docket No. FAA-2024-2023; Project Identifier MCAI-2023-01246-T]
FR document: [FR Doc. 2024-18478 Filed 8-20-24; 8:45 am]
Agency: Transportation Department
Sub Agency: Federal Aviation Administration
Official PDF Version: PDF Version
[top]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2024-2023; Project Identifier MCAI-2023-01246-T]
RIN 2120-AA64
Airworthiness Directives; 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 certain Bombardier, Inc., Model BD-100-1A10 airplanes. This proposed AD was prompted by uncommanded horizontal stabilizer motion during several in-service events caused by a problem with the trim switch wiring. This proposed AD would require installing the pitch/roll trim switch relays. 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 October 7, 2024.
ADDRESSES:
You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:
[top] • Federal eRulemaking Portal: Go to regulations.gov. Follow the instructions for submitting comments.
• Fax: 202-493-2251.
• 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.
AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA-2024-2023; 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.
Material Incorporated by Reference:
• For Bombardier material identified in this proposed AD, contact Bombardier Business Aircraft Customer Response Center, 400 Côte-Vertu Road West, Dorval, Québec H4S 1Y9, Canada; phone 514-855-2999; email ac.yul@aero.bombardier.com; website bombardier.com.
• You may view this material 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.
FOR FURTHER INFORMATION CONTACT:
Steven Dzierzynski, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; 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-2024-2023; Project Identifier MCAI-2023-01246-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 regulations.gov, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this NPRM.
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 Steven Dzierzynski, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov. Any commentary that the FAA receives that is not specifically designated as CBI will be placed in the public docket for this rulemaking.
Background
Transport Canada, which is the aviation authority for Canada, has issued Transport Canada AD CF-2023-77, dated December 7, 2023 (Transport Canada AD CF-2023-77) (also referred to after this as the MCAI), to correct an unsafe condition on certain Bombardier, Inc., Model BD-100-1A10 airplanes. The MCAI states that during several in-service events, following a STAB TRIM FAULT advisory message and an auto-pilot disconnect, both pilot and co-pilot commands to trim the horizontal stabilizer nose-up resulted in a nose-down movement of the horizontal stabilizer. In some events, the horizontal stabilizer reached the full travel nose-down position before the crew recognized the nature of the problem, and quickly recovered control of the airplane for safe landing. Transport Canada issued AD CF-2022-03, dated February 1, 2022 (Transport Canada AD CF-2022-03) (which corresponds to FAA AD 2022-12-02 (87 FR 34125, June 6, 2022)), as a mitigating action to require the use of an Expanded Pitch Trim Pre-Flight Check, the use of Trim Malfunction procedures, the revision of the AP STAB TRIM FAIL caution and STAB TRIM FAULT advisory procedures to address this unsafe condition. During the ongoing investigation by Bombardier and the supplier of the horizontal stabilizer pitch/roll trim switch (trim switch), Bombardier determined that one of the springs within the trim switch had failed. The supplier of the spring was changed in 2019. The majority of observed trim switch failures occurred in trim switches that were manufactured after 2019. Consequently, Transport Canada issued AD CF-2022-24, dated May 2, 2022 (Transport Canada AD CF-2022-24) (which corresponds to FAA AD 2023-02-01 (88 FR 7856, February 7, 2023)), to remove and replace the defective springs in the affected fleet. At that time, Bombardier also found an existing issue with the trim switch wiring installation. The problem with the trim switch wiring was identified as the main cause of the in-service unintended horizontal stabilizer motion events. On this airplane model, manual trim is accomplished by enabling the trim function by both pressing down on the trim switch and simultaneously moving the switch up, down, left, or right, as required to command trim in pitch or roll. The current wiring of the system is such that an enable signal originating from either the pilot-side or the copilot-side trim switch will enable both sides. By design, the pilot-side trim commands have priority over the copilot-side trim commands. Thus, if trim is enabled via the copilot-side trim switch, and the pilot-side trim switch malfunctions, it is possible for trim to move uncommanded or opposite to the intended direction. Transport Canada AD CF-2023-77 requires changes to the trim switch wiring installation to ensure the pilot and co-pilot trim Enable/Arm switch signals remain segregated in both roll and pitch axes.
The FAA is proposing this AD to address the problem with the trim switch wiring, which is the main cause of the uncommanded horizontal stabilizer motion. The unsafe condition, if not addressed, could result in increased crew workload and reduced safety margins, and if the flightcrew is unable to regain control of the horizontal stabilizer, would result in loss of control of the airplane and high control forces.
You may examine the MCAI in the AD docket at regulations.gov under Docket No. FAA-2024-2023.
Material Incorporated by Reference Under 1 CFR Part 51
[top] The FAA reviewed Bombardier Service Bulletin 100-27-22 and Bombardier Service Bulletin 350-27-012, both dated December 29, 2022. The material specifies procedures to install the pitch/roll trim switch relays. The
This material 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 this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI and material referenced above. The FAA is issuing this NPRM after determining that the unsafe condition described previously is likely to exist or develop on other products of the same type design.
Proposed AD Requirements in This NPRM
This proposed AD would require accomplishing the actions specified in the material already described.
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would affect 359 airplanes of U.S. registry. The FAA estimates the following costs to comply with this proposed AD:
| Labor cost | Parts cost | Cost per product | Cost on U.S. operators |
|---|---|---|---|
| Up to 45 work-hours × $85 per hour = Up to $3,825 | $3,582 | Up to $7,407 | Up to $2,659,113. |
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
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:
Bombardier, Inc.: Docket No. FAA-2024-2023; Project Identifier MCAI-2023-01246-T.
(a) Comments Due Date
The FAA must receive comments on this airworthiness directive (AD) by October 7, 2024.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Bombardier, Inc., Model BD-100-1A10 airplanes, certificated in any category, serial numbers 20003 through 20500 inclusive and 20501 through 20936 inclusive.
(d) Subject
Air Transport Association (ATA) of America Code 27, Flight controls.
(e) Unsafe Condition
This AD was prompted by uncommanded horizontal stabilizer motion during several in-service events caused by a problem with the trim switch wiring. The FAA is issuing this AD to address the problem with the trim switch wiring. The unsafe condition, if not addressed, could result in increased crew workload and reduced safety margins, and if the flightcrew is unable to regain control of the horizontal stabilizer, would result in loss of control of the airplane and high control forces.
(f) Compliance
Comply with this AD within the compliance times specified, unless already done.
(g) Installation of Pitch/Roll Trim Switch Relays and Tests
Within 3,000 flight hours or 5 years, whichever occurs first, from the effective date of this AD, install the pitch/roll trim switch relays, in accordance with sections 2.B. and 2.C. of the Accomplishment Instructions of the applicable material specified in paragraph (g)(1) or (2) of this AD.
(1) Bombardier Service Bulletin 100-27-22, dated December 29, 2022 (for airplane serial numbers 20003 through 20500 inclusive).
(2) Bombardier Service Bulletin 350-27-012, dated December 29, 2022 (for airplane serial numbers 20501 through 20936 inclusive).
(h) Additional AD Provisions
The following provisions also apply to this AD:
[top] (1) Alternative Methods of Compliance (AMOCs): 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 responsible Flight Standards Office, as appropriate. If sending information directly to the manager of the International Validation
(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, International Validation Branch, FAA; or Transport Canada; or Bombardier, Inc.'s Transport Canada Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature.
(i) Additional Information
For more information about this AD, contact Steven Dzierzynski, Aviation Safety Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7300; email 9-avs-nyaco-cos@faa.gov.
(j) Material Incorporated by Reference
(1) The Director of the Federal Register approved the incorporation by reference of the material listed in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this material as applicable to do the actions required by this AD, unless this AD specifies otherwise.
(i) Bombardier Service Bulletin 100-27-22, dated December 29, 2022.
(ii) Bombardier Service Bulletin 350-27-012, dated December 29, 2022.
(3) For Bombardier material identified in this AD, contact Bombardier Business Aircraft Customer Response Center, 400 Côte-Vertu Road West, Dorval, Québec H4S 1Y9, Canada; phone 514-855-2999; email ac.yul@aero.bombardier.com; website bombardier.com.
(4) You may view this material 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.
(5) You may view this material at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email fr.inspection@nara.gov.
Issued on August 12, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft Certification Service.
[FR Doc. 2024-18478 Filed 8-20-24; 8:45 am]
BILLING CODE 4910-13-P