Airworthiness Directives; Bombardier, Inc., Airplanes, 10408-10411 [2018-04720]

Download as PDF 10408 Federal Register / Vol. 83, No. 47 / Friday, March 9, 2018 / Proposed Rules DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2018–0160; Product Identifier 2017–NM–139–AD] RIN 2120–AA64 Airworthiness Directives; Bombardier, Inc., Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: We propose to supersede Airworthiness Directive (AD) 2016–24– 03, which applies to certain Bombardier, Inc., Model DHC–8–400 series airplanes. AD 2016–24–03 requires repetitive detailed inspections of barrel nuts and cradles, a check of the bolt torque of the preload indicating (PLI) washers, and corrective actions if necessary. Since we issued AD 2016– 24–03, the manufacturer has developed a modification that, when incorporated, terminates the repetitive inspections. This proposed AD would require modifying the airplane by installing a sealing disk to a certain location and replacing certain barrel nuts. We are proposing this AD to address the unsafe condition on these products. DATES: We must receive comments on this proposed AD by April 23, 2018. 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 http://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 service information identified in this NPRM, contact Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416–375– 4000; fax 416–375–4539; email thd.qseries@aero.bombardier.com; internet http://www.bombardier.com. You may view this referenced service information at the FAA, Transport Standards Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. amozie on DSK30RV082PROD with PROPOSALS SUMMARY: VerDate Sep<11>2014 15:54 Mar 08, 2018 Jkt 244001 Examining the AD Docket You may examine the AD docket on the internet at http:// www.regulations.gov by searching for and locating Docket No. FAA–2018– 0160; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this proposed AD, the regulatory evaluation, any comments received, and other information. The street address for the Docket Operations office (telephone 800–647–5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt. FOR FURTHER INFORMATION CONTACT: Aziz Ahmed, Aerospace Engineer, Airframe and Mechanical Systems Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7329; fax 516–794–5531. SUPPLEMENTARY INFORMATION: stabilizer attachment joints and lead to loss of control of the airplane. Comments Invited We invite you to send any written relevant data, views, or arguments about this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include ‘‘Docket No. FAA–2018–0160; Product Identifier 2017–NM–139–AD’’ at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this proposed AD. We will consider all comments received by the closing date and may amend this proposed AD based on those comments. We will post all comments we receive, without change, to http:// www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this proposed AD. There has been one in-service report of a cracked and corroded barrel nut, part number (P/N) DSC228–12, found at the mid-spar location of the horizontal stabilizer to vertical stabilizer attachment joint. There have also been two other reports of corroded barrel nuts found at mid-spar locations. Preliminary investigation determined that the cracking is initiated by corrosion. Further investigation confirmed that the corrosion was caused by inadequate cadmium plating on the barrel nuts. Failure of the barrel nuts could compromise the structural integrity of the joint and could lead to loss of control of the aeroplane. The original version of this [Canadian] AD was issued to mandate the initial and repetitive inspections of the barrel nuts [and cradles for cracks and corrosion] at each of the horizontal stabilizer to vertical stabilizer attachment joints. Revision 1 of this [Canadian] AD is issued to terminate the repetitive inspection requirement by requiring the incorporation of a modification to install a sealing disc at the middle spar location of the horizontal stabilizer to vertical stabilizer attachment joint, and the replacement of the DSC228 series barrel nuts with B0203073 series barrel nuts that are more resistant to corrosion. The applicability has been changed to account for the introduction of the modifications in production. Discussion We issued AD 2016–24–03, Amendment 39–18720 (81 FR 88623, December 8, 2016) (‘‘AD 2016–24–03’’), for certain Bombardier, Inc., Model DHC–8–400 series airplanes. AD 2016– 24–03 requires repetitive detailed inspections of barrel nuts and cradles, a check of the bolt torque of the PLI washers, and corrective action if necessary. AD 2016–24–03 resulted from reports of cracked and corroded barrel nuts found at the mid-spar location of the horizontal-stabilizer-tovertical-stabilizer attachment joint. We issued AD 2016–24–03 to detect and correct cracked and corroded barrel nuts, which could compromise the structural integrity of the vertical- PO 00000 Frm 00002 Fmt 4702 Sfmt 4702 Actions Since AD 2016–24–03 Was Issued Since we issued AD 2016–24–03, Bombardier, Inc. has issued new service information that describes a modification. We have determined that accomplishment of this modification will address the unsafe condition and terminate the repetitive inspections required by AD 2016–24–03. This modification was applied to certain airplanes in production. Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian Airworthiness Directive CF–2015–13R1, dated June 26, 2017 (referred to after this as the Mandatory Continuing Airworthiness Information, or ‘‘the MCAI’’), to correct an unsafe condition for certain Bombardier, Inc., Model DHC–8–400 series airplanes. The MCAI states: Required actions include a bolt preload check of the PLI washers and applicable corrective actions (retorque of the bolts and replacement of the barrel nut), a detailed inspection of cracked or broken barrel nuts for damaged bores of the fittings, replacement of discrepant barrel nuts (those with signs of structural damaged, corrosion, or cracking, or having a part number other than B0203073 series), adding an aluminum sealing disk to the E:\FR\FM\09MRP1.SGM 09MRP1 10409 Federal Register / Vol. 83, No. 47 / Friday, March 9, 2018 / Proposed Rules mid-spar barrel nut bore, and repair of damage and corrosion. You may examine the MCAI in the AD docket on the internet at http:// www.regulations.gov by searching for and locating Docket No. FAA–2018– 0160. Explanation of Changes From AD 2016– 24–03 In paragraph (h)(2) of AD 2016–24–03, we stated ‘‘. . . replace the barrel nut accomplish corrective actions in accordance with [methods approved by the FAA, TCCA, or Bombardier’s TCCA Design Approval Organization].’’ We intended to match the language in the MCAI and allow operators to either replace the discrepant barrel nut in accordance with the applicable service information or to request an alternative method of compliance (AMOC). In addition, we left ‘‘paragraph (h)(2)’’ out of the credit paragraph in AD 2016–24– 03. We have updated the retained requirements in this proposed AD to correct those errors. Related Service Information Under 1 CFR Part 51 Bombardier, Inc. has issued the following service information. • Bombardier Service Bulletin 84–55– 06, dated January 31, 2017. The service information describes procedures for installing an aluminum sealing disk at the mid-spar location of the vertical stabilizer. • Bombardier Service Bulletin 84–55– 08, Revision A, dated August 2, 2017. The service information describes procedures for an inspection for part number and damage of the barrel nuts at the horizontal-to-vertical-stabilizer attachment joints, and replacement of discrepant parts. 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 and Requirements of This Proposed AD This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are proposing this AD because we evaluated all pertinent information and determined an unsafe condition exists and 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 The applicability of Canadian AD CF– 2015–13R1, dated June 26, 2017, is limited to Bombardier, Inc., Model DHC–8–400, –401 and –402 airplanes, serial numbers 4001 through 4547. However, the applicability of this proposed AD includes Bombardier, Inc., Model DHC–8–400, –401 and –402 airplanes, serial numbers 4001 and subsequent. Because the affected barrel nuts are rotable parts, we have determined that discrepant parts could later be installed on airplanes that were initially delivered with B0203073 series barrel nuts, thereby subjecting those airplanes to the unsafe condition. Costs of Compliance We estimate that this proposed AD affects 54 airplanes of U.S. registry. We estimate the following costs to comply with this proposed AD: ESTIMATED COSTS Cost per product Parts cost Cost on U.S. operators Action Labor cost Inspections (retained actions from AD 2016– 24–03). Sealing disk installation (new proposed action). Replacement of DSC228 series barrel nuts (new proposed action). 8 work-hours × $85 per hour = $680 ............. $0 $680 $36,720 4 work-hours × $85 per hour = $340 ............. 781 1,121 60,534 2 work-hours × $85 per hour = $170 ............. 2,236 2,406 129,924 We estimate the following costs to do any necessary replacements that would be required based on the results of the inspection. We have no way of determining the number of aircraft that might need these replacements: ON-CONDITION COSTS Action Labor cost Replacement (retained action from AD 2016–24–03) amozie on DSK30RV082PROD with PROPOSALS We have received no definitive data that would enable us to provide cost estimates for the on-condition actions specified in this proposed AD. 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 VerDate Sep<11>2014 15:54 Mar 08, 2018 Jkt 244001 2 work-hours × $85 per hour = $170 ........................... detail the scope of the Agency’s authority. We are 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 PO 00000 Parts cost Frm 00003 Fmt 4702 Sfmt 4702 $8,881 Cost per product $9,051 because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action. This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has E:\FR\FM\09MRP1.SGM 09MRP1 10410 Federal Register / Vol. 83, No. 47 / Friday, March 9, 2018 / Proposed Rules delegated the authority to issue ADs applicable to transport category airplanes to the Director of the System Oversight Division. Regulatory Findings We 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. Is not a ‘‘significant rule’’ under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 3. Will not affect intrastate aviation in Alaska; and 4. 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 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 removing Airworthiness Directive (AD) 2016–24–03, Amendment 39–18720 (81 FR 88623, December 8, 2016), and adding the following new AD: ■ amozie on DSK30RV082PROD with PROPOSALS Bombardier, Inc.: Docket No. FAA–2018– 0160; Product Identifier 2017–NM–139– AD. (a) Comments Due Date We must receive comments by April 23, 2018. (b) Affected ADs This AD replaces AD 2016–24–03, Amendment 39–18720 (81 FR 88623, December 8, 2016) (‘‘AD 2016–24–03’’). (c) Applicability This AD applies to Bombardier, Inc., Model DHC–8–400, –401 and –402 airplanes, VerDate Sep<11>2014 15:54 Mar 08, 2018 Jkt 244001 certificated in any category, serial numbers 4001 and subsequent. (d) Subject Air Transport Association (ATA) of America Code 55, Stabilizers. (e) Reason This AD was prompted by reports of cracked and corroded barrel nuts found at the mid-spar location of the horizontal-stabilizerto-vertical-stabilizer attachment joint, and the issuance of new service information that includes a terminal modification. We are issuing this AD to detect and correct cracked and corroded barrel nuts, which could compromise the structural integrity of the vertical-stabilizer attachment joints and lead to loss of control of the airplane. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Retained Detailed Inspection of Barrel Nuts for Cracks and Corrosion, With No Changes This paragraph restates the requirements of paragraphs (g)(1) and (g)(2) of AD 2016–24– 03, with no changes. (1) For airplanes that have accumulated 5,400 flight hours or more, or have been in service 32 months or more since the date of issuance of the original certificate of airworthiness or the date of issuance of the original export certificate of airworthiness, as of January 12, 2017 (the effective date of AD 2016–24–03): Within 600 flight hours or 4 months, whichever occurs first after January 12, 2017, do a detailed visual inspection for signs of cracks and corrosion of the barrel nut and cradle, in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Alert Service Bulletin A84–55–04, Revision C, dated May 3, 2016. (2) For airplanes that have less than 5,400 flight hours, and have been in-service for less than 32 months since the date of issuance of the original certificate of airworthiness or the date of issuance of the original export certificate of airworthiness, as of January 12, 2017: Before the accumulation of 6,000 total flight hours or 36 months since the date of issuance of the original certificate of airworthiness or the date of issuance of the original export certificate of airworthiness, whichever occurs first, do a detailed visual inspection of the barrel nut for signs of cracks and corrosion of the barrel nut and cradle, in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Alert Service Bulletin A84–55–04, Revision C, dated May 3, 2016. (h) Retained Corrective Actions, Detailed Inspection, and Repetitive Inspections, With New Service Information, Reference to Terminating Action, and Reference to Corrective Actions This paragraph restates the requirements of paragraph (h) of AD 2016–24–03, with new service information and terminating action. Depending on the findings of any inspection required by paragraphs (g) and (j) of this AD, PO 00000 Frm 00004 Fmt 4702 Sfmt 4702 do the applicable actions in paragraphs (h)(1), (h)(2), (h)(3), and (h)(4) of this AD. Accomplishment of the actions required by paragraphs (l) and (m) of this AD, as applicable, terminates the requirements of this paragraph. (1) If any barrel nut or cradle is found cracked or broken, before further flight, replace the barrel nut and associated hardware, in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Service Bulletin 84–55–08, Revision A, dated August 2, 2017. (i) Concurrently with the replacement of any barrel nut, do a detailed inspection for corrosion and damage of the bore of the fitting, in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Service Bulletin 84–55–08, Revision A, dated August 2, 2017, and, before further flight, repair all corrosion and damage, in accordance with Bombardier Repair Drawing (RD) 8/4–55–1143, Issue 1, dated May 21, 2015. If the bore of the fitting cannot be repaired in accordance with Bombardier RD 8/4–55–1143, Issue 1, dated May 21, 2015, accomplish corrective actions in accordance with the procedures specified in paragraph (q)(2) of this AD. (ii) Within 600 flight hours or 4 months, whichever occurs first, after the replacement of a cracked barrel nut, replace the remaining barrel nuts and their associated hardware at the horizontal-stabilizer-to-vertical-stabilizer attachment joints, in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Service Bulletin 84–55–08, Revision A, dated August 2, 2017. (2) If any corrosion is found on any barrel nut on the front or rear-spar joints, before further flight, replace the barrel nut in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Service Bulletin 84–55–08, Revision A, dated August 2, 2017, or accomplish corrective actions in accordance with the procedures specified in paragraph (q)(2) of this AD. (3) If any corrosion above level 1, as defined in Bombardier Alert Service Bulletin A84–55–04, Revision C, dated May 3, 2016, is found on a barrel nut at the mid-spar joint, before further flight, replace the barrel nut and accomplish corrective actions in accordance with the procedures specified in paragraph (q)(2) of this AD. (4) If all corrosion found is at level 1 or below, as defined in Bombardier Alert Service Bulletin A84–55–04, Revision C, dated May 3, 2016, on a barrel nut at the midspar joint, repeat the inspection specified in paragraph (g) of this AD at intervals not to exceed 600 flight hours or 4 months, whichever occurs first, until completion of the actions required by paragraph (k) of this AD. (i) Retained Preload Indicating (PLI) Washer Check, With New Terminating Action This paragraph restates the requirements of paragraph (i) of AD 2016–24–03, with new terminating action. For airplanes with PLI washers installed at the front and rear-spar joints, before further flight after accomplishing any inspection required by E:\FR\FM\09MRP1.SGM 09MRP1 Federal Register / Vol. 83, No. 47 / Friday, March 9, 2018 / Proposed Rules paragraph (g) of this AD and all applicable corrective actions required by paragraph (h) of this AD, check the bolt preload, and do all applicable corrective actions, in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Alert Service Bulletin A84–55–04, Revision C, dated May 3, 2016. Do all applicable corrective actions before further flight. Accomplishment of the actions required by paragraphs (l) and (m) of this AD, as applicable, terminates the requirements of this paragraph. (j) Retained Repetitive Inspection Interval, With New Terminating Action This paragraph restates the requirements of paragraph (j) of AD 2016–24–03, with new terminating action. Repeat the inspection and preload check required by paragraphs (g) and (i) of this AD at intervals not to exceed 3,600 flight hours or 18 months, whichever occurs first, except as provided by paragraph (k) of this AD. Accomplishment of the actions required by paragraphs (l) and (m) of this AD, as applicable, terminates the requirements of this paragraph. (k) Retained Optional Barrel Nut Replacement, With New Service Information This paragraph restates the provisions of paragraph (k) of AD 2016–24–03, with new service information. Inspection and replacement of all barrel nuts at the horizontal-stabilizer-to-vertical-stabilizer attachment joints, in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Service Bulletin 84–55–08, Revision A, dated August 2, 2017, extends the next inspection required by paragraph (j) of this AD to within 6,000 flight hours or 36 months, whichever occurs first, after accomplishing the replacement. amozie on DSK30RV082PROD with PROPOSALS (l) New Requirement of This AD: Sealing Disk Installation Within 8,000 flight hours or 48 months, whichever occurs first, after the effective date of this AD, install a sealing disk at the midspar location of the vertical stabilizer in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Service Bulletin 84–55–06, dated January 31, 2017. Accomplishment of the actions required by paragraphs (l) and (m) of this AD, as applicable, terminates the requirements of paragraphs (h), (i), and (j) of this AD. (m) New Requirement of This AD: Replacement of DSC228 Series Barrel Nuts For Bombardier, Inc., Model DHC–8–400, –401 and –402 airplanes, serial numbers 4001 through 4524 inclusive: Within 8,000 flight hours or 48 months, whichever occurs first, after the effective date of this AD, replace all DSC228 series barrel nuts at the horizontal-stabilizer-to-vertical-stabilizer attachment joints with B0203073 series barrel nuts in accordance with paragraph 3.B., ‘‘Procedure,’’ of the Accomplishment Instructions of Bombardier Service Bulletin 84–55–08, Revision A, dated August 2, 2017. Accomplishment of the actions required by paragraphs (l) and (m) of this AD, as VerDate Sep<11>2014 15:54 Mar 08, 2018 Jkt 244001 applicable, terminates the requirements of paragraphs (h), (i), and (j) of this AD. (n) Parts Installation Prohibition After modification of an airplane as required by paragraphs (l) and (m) of this AD, no person may install a DSC228 series barrel nut at the horizontal-stabilizer-to-verticalstabilizer attachment joint on the modified airplane. (o) Terminating Actions Accomplishment of the actions required by paragraphs (l) and (m) of this AD, as applicable, terminates the requirements of paragraphs (h), (i), and (j) of this AD. (p) Credit for Previous Actions (1) This paragraph provides credit for actions required by paragraphs (g)(1), (g)(2), (h)(1), (h)(1)(i), (h)(1)(ii), (h)(2), (h)(3), (h)(4), (i), and (k) of this AD, if those actions were performed before the effective date of this AD using the service information identified in paragraphs (p)(1)(i) through (p)(1)(iii) of this AD. (i) Bombardier Alert Service Bulletin A84– 55–04, dated May 21, 2015, which is not incorporated by reference in this AD. (ii) Bombardier Alert Service Bulletin A84– 55–04, Revision A, dated June 2, 2015, which is not incorporated by reference in this AD. (iii) Bombardier Alert Service Bulletin A84–55–04, Revision B, dated July 30, 2015, which is not incorporated by reference in this AD. (2) This paragraph provides credit for actions required by paragraphs (h)(1), (h)(1)(i), (h)(1)(ii), (h)(2), and (k) of this AD, if those actions were performed before the effective date of this AD using the service information identified in paragraphs (p)(2)(i) and (p)(2)(ii) of this AD. (i) Bombardier Service Bulletin 84–55–08, dated January 27, 2017, which is not incorporated by reference in this AD. (ii) Bombardier Alert Service Bulletin A84– 55–04, Revision C, dated May 3, 2016, which was incorporated by reference in AD 2016– 24–03. (q) Other FAA AD Provisions (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. (i) 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. (ii) AMOCs approved previously for AD 2016–24–03 are approved as AMOCs for the corresponding provisions of this AD. (2) Contacting the Manufacturer: For any requirement in this AD to obtain corrective PO 00000 Frm 00005 Fmt 4702 Sfmt 4702 10411 actions from a manufacturer, the action must be accomplished using a method approved by the Manager, New York ACO Branch, FAA; or Transport Canada Civil Aviation (TCCA); or Bombardier, Inc.’s TCCA Design Approval Organization (DAO). If approved by the DAO, the approval must include the DAO-authorized signature. (r) Related Information (1) Refer to Mandatory Continuing Airworthiness Information (MCAI) TCCA Airworthiness Directive CF–2015–13R1, dated June 26, 2017, for related information. This MCAI may be found in the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA–2018–0160. (2) For more information about this AD, contact Aziz Ahmed, Aerospace Engineer, Airframe and Mechanical Systems Section, FAA, New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516–228–7329; fax 516–794–5531. (3) For service information identified in this AD, contact Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416–375–4000; fax 416–375–4539; email thd.qseries@aero.bombardier.com; internet http://www.bombardier.com. You may view this service information at the FAA, Transport Standards Branch, 2200 South 216th St., Des Moines, WA. For information on the availability of this material at the FAA, call 206–231–3195. Issued in Renton, Washington, on March 2, 2018. Michael Kaszycki, Acting Director, System Oversight Division, Aircraft Certification Service. [FR Doc. 2018–04720 Filed 3–8–18; 8:45 am] BILLING CODE 4910–13–P DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. FAA–2018–0165; Product Identifier 2017–NM–122–AD] RIN 2120–AA64 Airworthiness Directives; Airbus Airplanes Federal Aviation Administration (FAA), DOT. ACTION: Notice of proposed rulemaking (NPRM). AGENCY: We propose to adopt a new airworthiness directive (AD) for all Airbus Model A318–111 and –112 airplanes, Model A319–111, –112, –113, –114, and –115 airplanes, Model A320– 211, –212, –214, and –216 airplanes, and Model A321–111, –112, –211, –212, and –213 airplanes. This proposed AD was prompted by a report of a production quality deficiency on the SUMMARY: E:\FR\FM\09MRP1.SGM 09MRP1

Agencies

[Federal Register Volume 83, Number 47 (Friday, March 9, 2018)]
[Proposed Rules]
[Pages 10408-10411]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2018-04720]



[[Page 10408]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0160; Product Identifier 2017-NM-139-AD]
RIN 2120-AA64


Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede Airworthiness Directive (AD) 2016-24-
03, which applies to certain Bombardier, Inc., Model DHC-8-400 series 
airplanes. AD 2016-24-03 requires repetitive detailed inspections of 
barrel nuts and cradles, a check of the bolt torque of the preload 
indicating (PLI) washers, and corrective actions if necessary. Since we 
issued AD 2016-24-03, the manufacturer has developed a modification 
that, when incorporated, terminates the repetitive inspections. This 
proposed AD would require modifying the airplane by installing a 
sealing disk to a certain location and replacing certain barrel nuts. 
We are proposing this AD to address the unsafe condition on these 
products.

DATES: We must receive comments on this proposed AD by April 23, 2018.

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 http://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 service information identified in this NPRM, contact 
Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt Boulevard, 
Toronto, Ontario M3K 1Y5, Canada; telephone 416-375-4000; fax 416-375-
4539; email [email protected]; internet http://www.bombardier.com. You may view this referenced service information at 
the FAA, Transport Standards 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 http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
0160; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Operations office (telephone 800-647-5527) is in the ADDRESSES section. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Aziz Ahmed, Aerospace Engineer, 
Airframe and Mechanical Systems Section, FAA, New York ACO Branch, 1600 
Stewart Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7329; 
fax 516-794-5531.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2018-0160; 
Product Identifier 2017-NM-139-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this proposed AD. We will consider 
all comments received by the closing date and may amend this proposed 
AD based on those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We issued AD 2016-24-03, Amendment 39-18720 (81 FR 88623, December 
8, 2016) (``AD 2016-24-03''), for certain Bombardier, Inc., Model DHC-
8-400 series airplanes. AD 2016-24-03 requires repetitive detailed 
inspections of barrel nuts and cradles, a check of the bolt torque of 
the PLI washers, and corrective action if necessary. AD 2016-24-03 
resulted from reports of cracked and corroded barrel nuts found at the 
mid-spar location of the horizontal-stabilizer-to-vertical-stabilizer 
attachment joint. We issued AD 2016-24-03 to detect and correct cracked 
and corroded barrel nuts, which could compromise the structural 
integrity of the vertical-stabilizer attachment joints and lead to loss 
of control of the airplane.

Actions Since AD 2016-24-03 Was Issued

    Since we issued AD 2016-24-03, Bombardier, Inc. has issued new 
service information that describes a modification. We have determined 
that accomplishment of this modification will address the unsafe 
condition and terminate the repetitive inspections required by AD 2016-
24-03. This modification was applied to certain airplanes in 
production.
    Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued Canadian Airworthiness Directive CF-
2015-13R1, dated June 26, 2017 (referred to after this as the Mandatory 
Continuing Airworthiness Information, or ``the MCAI''), to correct an 
unsafe condition for certain Bombardier, Inc., Model DHC-8-400 series 
airplanes. The MCAI states:

    There has been one in-service report of a cracked and corroded 
barrel nut, part number (P/N) DSC228-12, found at the mid-spar 
location of the horizontal stabilizer to vertical stabilizer 
attachment joint. There have also been two other reports of corroded 
barrel nuts found at mid-spar locations.
    Preliminary investigation determined that the cracking is 
initiated by corrosion. Further investigation confirmed that the 
corrosion was caused by inadequate cadmium plating on the barrel 
nuts. Failure of the barrel nuts could compromise the structural 
integrity of the joint and could lead to loss of control of the 
aeroplane.
    The original version of this [Canadian] AD was issued to mandate 
the initial and repetitive inspections of the barrel nuts [and 
cradles for cracks and corrosion] at each of the horizontal 
stabilizer to vertical stabilizer attachment joints.
    Revision 1 of this [Canadian] AD is issued to terminate the 
repetitive inspection requirement by requiring the incorporation of 
a modification to install a sealing disc at the middle spar location 
of the horizontal stabilizer to vertical stabilizer attachment 
joint, and the replacement of the DSC228 series barrel nuts with 
B0203073 series barrel nuts that are more resistant to corrosion. 
The applicability has been changed to account for the introduction 
of the modifications in production.

    Required actions include a bolt preload check of the PLI washers 
and applicable corrective actions (retorque of the bolts and 
replacement of the barrel nut), a detailed inspection of cracked or 
broken barrel nuts for damaged bores of the fittings, replacement of 
discrepant barrel nuts (those with signs of structural damaged, 
corrosion, or cracking, or having a part number other than B0203073 
series), adding an aluminum sealing disk to the

[[Page 10409]]

mid-spar barrel nut bore, and repair of damage and corrosion.
    You may examine the MCAI in the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
0160.

Explanation of Changes From AD 2016-24-03

    In paragraph (h)(2) of AD 2016-24-03, we stated ``. . . replace the 
barrel nut accomplish corrective actions in accordance with [methods 
approved by the FAA, TCCA, or Bombardier's TCCA Design Approval 
Organization].'' We intended to match the language in the MCAI and 
allow operators to either replace the discrepant barrel nut in 
accordance with the applicable service information or to request an 
alternative method of compliance (AMOC). In addition, we left 
``paragraph (h)(2)'' out of the credit paragraph in AD 2016-24-03. We 
have updated the retained requirements in this proposed AD to correct 
those errors.

Related Service Information Under 1 CFR Part 51

    Bombardier, Inc. has issued the following service information.
     Bombardier Service Bulletin 84-55-06, dated January 31, 
2017. The service information describes procedures for installing an 
aluminum sealing disk at the mid-spar location of the vertical 
stabilizer.
     Bombardier Service Bulletin 84-55-08, Revision A, dated 
August 2, 2017. The service information describes procedures for an 
inspection for part number and damage of the barrel nuts at the 
horizontal-to-vertical-stabilizer attachment joints, and replacement of 
discrepant parts.
    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 and Requirements of This Proposed AD

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to our bilateral agreement with the State of Design Authority, we have 
been notified of the unsafe condition described in the MCAI and service 
information referenced above. We are proposing this AD because we 
evaluated all pertinent information and determined an unsafe condition 
exists and 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

    The applicability of Canadian AD CF-2015-13R1, dated June 26, 2017, 
is limited to Bombardier, Inc., Model DHC-8-400, -401 and -402 
airplanes, serial numbers 4001 through 4547. However, the applicability 
of this proposed AD includes Bombardier, Inc., Model DHC-8-400, -401 
and -402 airplanes, serial numbers 4001 and subsequent. Because the 
affected barrel nuts are rotable parts, we have determined that 
discrepant parts could later be installed on airplanes that were 
initially delivered with B0203073 series barrel nuts, thereby 
subjecting those airplanes to the unsafe condition.

Costs of Compliance

    We estimate that this proposed AD affects 54 airplanes of U.S. 
registry. We estimate the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
               Action                         Labor cost            Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Inspections (retained actions from   8 work-hours x $85 per hour              $0            $680         $36,720
 AD 2016-24-03).                      = $680.
Sealing disk installation (new       4 work-hours x $85 per hour             781           1,121          60,534
 proposed action).                    = $340.
Replacement of DSC228 series barrel  2 work-hours x $85 per hour           2,236           2,406         129,924
 nuts (new proposed action).          = $170.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary replacements 
that would be required based on the results of the inspection. We have 
no way of determining the number of aircraft that might need these 
replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                   Action                                 Labor cost                Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replacement (retained action from AD 2016-   2 work-hours x $85 per hour = $170.          $8,881          $9,051
 24-03).
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
cost estimates for the on-condition actions specified in this proposed 
AD.

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.
    We are 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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has

[[Page 10410]]

delegated the authority to issue ADs applicable to transport category 
airplanes to the Director of the System Oversight Division.

Regulatory Findings

    We 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. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979);
    3. Will not affect intrastate aviation in Alaska; and
    4. 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 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 removing Airworthiness Directive (AD) 
2016-24-03, Amendment 39-18720 (81 FR 88623, December 8, 2016), and 
adding the following new AD:

Bombardier, Inc.: Docket No. FAA-2018-0160; Product Identifier 2017-
NM-139-AD.

(a) Comments Due Date

    We must receive comments by April 23, 2018.

(b) Affected ADs

    This AD replaces AD 2016-24-03, Amendment 39-18720 (81 FR 88623, 
December 8, 2016) (``AD 2016-24-03'').

(c) Applicability

    This AD applies to Bombardier, Inc., Model DHC-8-400, -401 and -
402 airplanes, certificated in any category, serial numbers 4001 and 
subsequent.

(d) Subject

    Air Transport Association (ATA) of America Code 55, Stabilizers.

(e) Reason

    This AD was prompted by reports of cracked and corroded barrel 
nuts found at the mid-spar location of the horizontal-stabilizer-to-
vertical-stabilizer attachment joint, and the issuance of new 
service information that includes a terminal modification. We are 
issuing this AD to detect and correct cracked and corroded barrel 
nuts, which could compromise the structural integrity of the 
vertical-stabilizer attachment joints and lead to loss of control of 
the airplane.

(f) Compliance

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

(g) Retained Detailed Inspection of Barrel Nuts for Cracks and 
Corrosion, With No Changes

    This paragraph restates the requirements of paragraphs (g)(1) 
and (g)(2) of AD 2016-24-03, with no changes.
    (1) For airplanes that have accumulated 5,400 flight hours or 
more, or have been in service 32 months or more since the date of 
issuance of the original certificate of airworthiness or the date of 
issuance of the original export certificate of airworthiness, as of 
January 12, 2017 (the effective date of AD 2016-24-03): Within 600 
flight hours or 4 months, whichever occurs first after January 12, 
2017, do a detailed visual inspection for signs of cracks and 
corrosion of the barrel nut and cradle, in accordance with paragraph 
3.B., ``Procedure,'' of the Accomplishment Instructions of 
Bombardier Alert Service Bulletin A84-55-04, Revision C, dated May 
3, 2016.
    (2) For airplanes that have less than 5,400 flight hours, and 
have been in-service for less than 32 months since the date of 
issuance of the original certificate of airworthiness or the date of 
issuance of the original export certificate of airworthiness, as of 
January 12, 2017: Before the accumulation of 6,000 total flight 
hours or 36 months since the date of issuance of the original 
certificate of airworthiness or the date of issuance of the original 
export certificate of airworthiness, whichever occurs first, do a 
detailed visual inspection of the barrel nut for signs of cracks and 
corrosion of the barrel nut and cradle, in accordance with paragraph 
3.B., ``Procedure,'' of the Accomplishment Instructions of 
Bombardier Alert Service Bulletin A84-55-04, Revision C, dated May 
3, 2016.

(h) Retained Corrective Actions, Detailed Inspection, and Repetitive 
Inspections, With New Service Information, Reference to Terminating 
Action, and Reference to Corrective Actions

    This paragraph restates the requirements of paragraph (h) of AD 
2016-24-03, with new service information and terminating action. 
Depending on the findings of any inspection required by paragraphs 
(g) and (j) of this AD, do the applicable actions in paragraphs 
(h)(1), (h)(2), (h)(3), and (h)(4) of this AD. Accomplishment of the 
actions required by paragraphs (l) and (m) of this AD, as 
applicable, terminates the requirements of this paragraph.
    (1) If any barrel nut or cradle is found cracked or broken, 
before further flight, replace the barrel nut and associated 
hardware, in accordance with paragraph 3.B., ``Procedure,'' of the 
Accomplishment Instructions of Bombardier Service Bulletin 84-55-08, 
Revision A, dated August 2, 2017.
    (i) Concurrently with the replacement of any barrel nut, do a 
detailed inspection for corrosion and damage of the bore of the 
fitting, in accordance with paragraph 3.B., ``Procedure,'' of the 
Accomplishment Instructions of Bombardier Service Bulletin 84-55-08, 
Revision A, dated August 2, 2017, and, before further flight, repair 
all corrosion and damage, in accordance with Bombardier Repair 
Drawing (RD) 8/4-55-1143, Issue 1, dated May 21, 2015. If the bore 
of the fitting cannot be repaired in accordance with Bombardier RD 
8/4-55-1143, Issue 1, dated May 21, 2015, accomplish corrective 
actions in accordance with the procedures specified in paragraph 
(q)(2) of this AD.
    (ii) Within 600 flight hours or 4 months, whichever occurs 
first, after the replacement of a cracked barrel nut, replace the 
remaining barrel nuts and their associated hardware at the 
horizontal-stabilizer-to-vertical-stabilizer attachment joints, in 
accordance with paragraph 3.B., ``Procedure,'' of the Accomplishment 
Instructions of Bombardier Service Bulletin 84-55-08, Revision A, 
dated August 2, 2017.
    (2) If any corrosion is found on any barrel nut on the front or 
rear-spar joints, before further flight, replace the barrel nut in 
accordance with paragraph 3.B., ``Procedure,'' of the Accomplishment 
Instructions of Bombardier Service Bulletin 84-55-08, Revision A, 
dated August 2, 2017, or accomplish corrective actions in accordance 
with the procedures specified in paragraph (q)(2) of this AD.
    (3) If any corrosion above level 1, as defined in Bombardier 
Alert Service Bulletin A84-55-04, Revision C, dated May 3, 2016, is 
found on a barrel nut at the mid-spar joint, before further flight, 
replace the barrel nut and accomplish corrective actions in 
accordance with the procedures specified in paragraph (q)(2) of this 
AD.
    (4) If all corrosion found is at level 1 or below, as defined in 
Bombardier Alert Service Bulletin A84-55-04, Revision C, dated May 
3, 2016, on a barrel nut at the mid-spar joint, repeat the 
inspection specified in paragraph (g) of this AD at intervals not to 
exceed 600 flight hours or 4 months, whichever occurs first, until 
completion of the actions required by paragraph (k) of this AD.

(i) Retained Preload Indicating (PLI) Washer Check, With New 
Terminating Action

    This paragraph restates the requirements of paragraph (i) of AD 
2016-24-03, with new terminating action. For airplanes with PLI 
washers installed at the front and rear-spar joints, before further 
flight after accomplishing any inspection required by

[[Page 10411]]

paragraph (g) of this AD and all applicable corrective actions 
required by paragraph (h) of this AD, check the bolt preload, and do 
all applicable corrective actions, in accordance with paragraph 
3.B., ``Procedure,'' of the Accomplishment Instructions of 
Bombardier Alert Service Bulletin A84-55-04, Revision C, dated May 
3, 2016. Do all applicable corrective actions before further flight. 
Accomplishment of the actions required by paragraphs (l) and (m) of 
this AD, as applicable, terminates the requirements of this 
paragraph.

(j) Retained Repetitive Inspection Interval, With New Terminating 
Action

    This paragraph restates the requirements of paragraph (j) of AD 
2016-24-03, with new terminating action. Repeat the inspection and 
preload check required by paragraphs (g) and (i) of this AD at 
intervals not to exceed 3,600 flight hours or 18 months, whichever 
occurs first, except as provided by paragraph (k) of this AD. 
Accomplishment of the actions required by paragraphs (l) and (m) of 
this AD, as applicable, terminates the requirements of this 
paragraph.

(k) Retained Optional Barrel Nut Replacement, With New Service 
Information

    This paragraph restates the provisions of paragraph (k) of AD 
2016-24-03, with new service information. Inspection and replacement 
of all barrel nuts at the horizontal-stabilizer-to-vertical-
stabilizer attachment joints, in accordance with paragraph 3.B., 
``Procedure,'' of the Accomplishment Instructions of Bombardier 
Service Bulletin 84-55-08, Revision A, dated August 2, 2017, extends 
the next inspection required by paragraph (j) of this AD to within 
6,000 flight hours or 36 months, whichever occurs first, after 
accomplishing the replacement.

(l) New Requirement of This AD: Sealing Disk Installation

    Within 8,000 flight hours or 48 months, whichever occurs first, 
after the effective date of this AD, install a sealing disk at the 
mid-spar location of the vertical stabilizer in accordance with 
paragraph 3.B., ``Procedure,'' of the Accomplishment Instructions of 
Bombardier Service Bulletin 84-55-06, dated January 31, 2017. 
Accomplishment of the actions required by paragraphs (l) and (m) of 
this AD, as applicable, terminates the requirements of paragraphs 
(h), (i), and (j) of this AD.

(m) New Requirement of This AD: Replacement of DSC228 Series Barrel 
Nuts

    For Bombardier, Inc., Model DHC-8-400, -401 and -402 airplanes, 
serial numbers 4001 through 4524 inclusive: Within 8,000 flight 
hours or 48 months, whichever occurs first, after the effective date 
of this AD, replace all DSC228 series barrel nuts at the horizontal-
stabilizer-to-vertical-stabilizer attachment joints with B0203073 
series barrel nuts in accordance with paragraph 3.B., ``Procedure,'' 
of the Accomplishment Instructions of Bombardier Service Bulletin 
84-55-08, Revision A, dated August 2, 2017. Accomplishment of the 
actions required by paragraphs (l) and (m) of this AD, as 
applicable, terminates the requirements of paragraphs (h), (i), and 
(j) of this AD.

(n) Parts Installation Prohibition

    After modification of an airplane as required by paragraphs (l) 
and (m) of this AD, no person may install a DSC228 series barrel nut 
at the horizontal-stabilizer-to-vertical-stabilizer attachment joint 
on the modified airplane.

(o) Terminating Actions

    Accomplishment of the actions required by paragraphs (l) and (m) 
of this AD, as applicable, terminates the requirements of paragraphs 
(h), (i), and (j) of this AD.

(p) Credit for Previous Actions

    (1) This paragraph provides credit for actions required by 
paragraphs (g)(1), (g)(2), (h)(1), (h)(1)(i), (h)(1)(ii), (h)(2), 
(h)(3), (h)(4), (i), and (k) of this AD, if those actions were 
performed before the effective date of this AD using the service 
information identified in paragraphs (p)(1)(i) through (p)(1)(iii) 
of this AD.
    (i) Bombardier Alert Service Bulletin A84-55-04, dated May 21, 
2015, which is not incorporated by reference in this AD.
    (ii) Bombardier Alert Service Bulletin A84-55-04, Revision A, 
dated June 2, 2015, which is not incorporated by reference in this 
AD.
    (iii) Bombardier Alert Service Bulletin A84-55-04, Revision B, 
dated July 30, 2015, which is not incorporated by reference in this 
AD.
    (2) This paragraph provides credit for actions required by 
paragraphs (h)(1), (h)(1)(i), (h)(1)(ii), (h)(2), and (k) of this 
AD, if those actions were performed before the effective date of 
this AD using the service information identified in paragraphs 
(p)(2)(i) and (p)(2)(ii) of this AD.
    (i) Bombardier Service Bulletin 84-55-08, dated January 27, 
2017, which is not incorporated by reference in this AD.
    (ii) Bombardier Alert Service Bulletin A84-55-04, Revision C, 
dated May 3, 2016, which was incorporated by reference in AD 2016-
24-03.

(q) Other FAA AD Provisions

    (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.
    (i) 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.
    (ii) AMOCs approved previously for AD 2016-24-03 are approved as 
AMOCs for the corresponding provisions of this AD.
    (2) Contacting the Manufacturer: For any requirement in this AD 
to obtain corrective actions from a manufacturer, the action must be 
accomplished using a method approved by the Manager, New York ACO 
Branch, FAA; or Transport Canada Civil Aviation (TCCA); or 
Bombardier, Inc.'s TCCA Design Approval Organization (DAO). If 
approved by the DAO, the approval must include the DAO-authorized 
signature.

(r) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) TCCA Airworthiness Directive CF-2015-13R1, dated June 26, 
2017, for related information. This MCAI may be found in the AD 
docket on the internet at http://www.regulations.gov by searching 
for and locating Docket No. FAA-2018-0160.
    (2) For more information about this AD, contact Aziz Ahmed, 
Aerospace Engineer, Airframe and Mechanical Systems Section, FAA, 
New York ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 
11590; telephone 516-228-7329; fax 516-794-5531.
    (3) For service information identified in this AD, contact 
Bombardier, Inc., Q-Series Technical Help Desk, 123 Garratt 
Boulevard, Toronto, Ontario M3K 1Y5, Canada; telephone 416-375-4000; 
fax 416-375-4539; email [email protected]; internet 
http://www.bombardier.com. You may view this service information at 
the FAA, Transport Standards Branch, 2200 South 216th St., Des 
Moines, WA. For information on the availability of this material at 
the FAA, call 206-231-3195.

    Issued in Renton, Washington, on March 2, 2018.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2018-04720 Filed 3-8-18; 8:45 am]
BILLING CODE 4910-13-P