2022-07083. Airworthiness Directives; De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Final rule.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for all De Havilland Aircraft of Canada Limited Model DHC-8-401 and -402 airplanes. This AD was prompted by reports of bleed air leaks in the wing box area and failure of the leak detection shroud. This AD requires removing and inspecting the affected V-band coupling and check valve seals, doing corrective actions if necessary, and replacing the coupling and seals with a redesigned assembly. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective May 10, 2022.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of May 10, 2022.

ADDRESSES:

For service information identified in this final rule, contact De Havilland Aircraft of Canada Limited, Q-Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone [phone]; fax [phone]; email [e-mail]; internet https://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. It is also available on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-1068.

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-2021-1068; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, any comments received, and other information. The address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

Elizabeth Dowling, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone [phone]; email [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued TCCA AD CF-2021-11, dated March 29, 2021 (TCCA AD CF-2021-11) (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for all De Havilland Aircraft of Canada Limited Model DHC-8-401 and -402 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-2021-1068.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to all De Havilland Aircraft of Canada Limited Model DHC-8-401 and -402 airplanes. The NPRM published in the Federal Register on December 17, 2021 (86 FR 71594). The NPRM was prompted by reports of bleed air leaks in the wing box area and failure of the leak detection shroud. The NPRM proposed to require removing and inspecting the affected V-band coupling and check valve seals, doing corrective actions if necessary, and replacing the coupling and seals with a redesigned assembly. The FAA is issuing this AD to address the possibility of undetected hot engine bleed air being directed onto aircraft structure, the main landing gear (MLG) emergency release cable, and the static air temperature (SAT) sensor, which could cause the main landing gear emergency release cable to malfunction. See the MCAI for additional background information.

Comments

The FAA gave the public the opportunity to participate in developing this final rule. The FAA has considered the comment received. The Air Line Pilots Association, International (ALPA), indicated its support for NPRM.

Conclusion

The FAA reviewed the relevant data, considered the comment received, and determined that air safety and the public interest require adopting this final rule as proposed, except for minor editorial changes. The FAA has determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for addressing the unsafe condition; and
• Do not add any additional burden upon the public than was already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

De Havilland Aircraft of Canada Limited has issued Service Bulletin 84-36-06, dated December 15, 2020. This service information describes procedures for removing the affected V-band coupling and check valve seals, doing a visual inspection of the coupling covers and surrounding area for damage due to bleed air leakage, and replacing the coupling and seals with a redesigned assembly.

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.

Costs of Compliance

The FAA estimates that this AD affects 82 airplanes of U.S. registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

Labor cost	Parts cost	Cost per product	Cost on U.S. operators
4 work-hours × $85 per hour = $340	$75	$415	$34,030

The FAA estimates the following costs to do any necessary coupling cover replacement that would be required based on the results of any required actions. The FAA has no way of determining the number of aircraft that might need this on-condition action:

Estimated Costs of On-Condition Action

Labor cost	Parts cost	Cost per product
1 work-hour × $85 per hour = $85	$5	$90

The FAA has received no definitive data on which to base the cost estimates for correcting damage in the area surrounding the coupling covers.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, section 106, describes the authority of the FAA Administrator. Subtitle VII: Aviation Programs, describes in more detail the scope of the Agency's authority.

The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701: General requirements. Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

This AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

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

(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Amendment

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

PART 39—AIRWORTHINESS DIRECTIVES

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:

2022-06-15 De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.): Amendment 39-21981; Docket No. FAA-2021-1068; Project Identifier MCAI-2021-00383-T.

(a) Effective Date

This airworthiness directive (AD) is effective May 10, 2022.

(b) Affected ADs

None.

(c) Applicability

This AD applies to all De Havilland Aircraft of Canada Limited (Type Certificate Previously Held by Bombardier, Inc.) Model DHC-8-401 and -402 airplanes, certificated in any category.

(d) Subject

Air Transport Association (ATA) of America Code 36, Pneumatic.

(e) Unsafe Condition

This AD was prompted by reports of bleed air leaks in the wing box area and failure of the leak detection shroud. The FAA is issuing this AD to address the possibility of undetected hot engine bleed air being directed onto aircraft structure, the main landing gear (MLG) emergency release cable, and the static air temperature (SAT) sensor, which could cause the main landing gear emergency release cable to malfunction.

(f) Compliance

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

(g) Required Actions

Within 48 months or 8,000 flight hours, whichever occurs first, from the effective date of this AD: Remove the affected V-band coupling and check valve seals, do a visual inspection for damage to the coupling covers and surrounding area, and replace the coupling and seals with a redesigned assembly, in accordance with the Accomplishment Instructions, paragraph 3.B., of de Havilland Service Bulletin 84-36-06, dated December 15, 2020.

(1) If any damage to a coupling cover is found, replace the coupling cover before further flight in accordance with the Accomplishment Instructions of de Havilland Service Bulletin 84-36-06, dated December 15, 2020.

(2) If any damage to the surrounding area is found, before further flight, accomplish corrective actions in accordance with the procedures specified in paragraph (i)(2) of this AD.

(h) Parts Installation Prohibition

As of the effective date of this AD, no person may install a V-band coupling, part number (P/N) DSC361-250, or check valve seal, P/N MS35769-71, in the center wing front spar area of any airplane.

(i) 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 [phone]. 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 DAO-authorized signature.

(j) Related Information

(1) Refer to Mandatory Continuing Airworthiness Information (MCAI) TCCA AD CF-2021-11, dated March 29, 2021, 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-2021-1068.

(2) For more information about this AD, contact Elizabeth Dowling, Aerospace Engineer, Mechanical Systems and Administrative Services Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone [phone]; email [e-mail].

(k) Material Incorporated by Reference

(1) The Director of the Federal Register approved the incorporation by reference (IBR) 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 this AD specifies otherwise.

(i) De Havilland Aircraft of Canada Limited Service Bulletin 84-36-06, dated December 15, 2020.

(ii) [Reserved]

(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 [phone]; fax [phone]; email [e-mail]; internet https://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.

(4) 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.

(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 [e-mail], or go to: https://www.archives.gov/​federal-register/​cfr/​ibr-locations.html.

Issued on March 10, 2022.

Lance T. Gant,

Director, Compliance & Airworthiness Division, Aircraft Certification Service.