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 Department of Transportation Federal Aviation Administration 14 CFR Part 39
[Docket No. FAA-2018-0634; Product Identifier 2018-NM-050-AD]
RIN 2120-AA64
 AGENCY: Federal Aviation Administration (FAA), DOT.
 ACTION: Notice of proposed rulemaking (NPRM).
 SUMMARY: We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc., Model CL-600-2C10 (Regional Jet Series 700, 701 & 702) airplanes, Model CL-600-2D15 (Regional Jet Series 705) airplanes, Model CL-600-2D24 (Regional Jet Series 900) airplanes, and Model CL-600-2E25 (Regional Jet Series 1000) airplanes. This proposed AD was prompted by reports of a fractured main landing gear (MLG) orifice support tube (OST). This proposed AD would require replacing the MLG OST, and revising the maintenance or inspection program, as applicable, to incorporate new or more restrictive maintenance requirements and airworthiness limitations. We are proposing this AD to address the unsafe condition on these products.
 DATES: We must receive comments on this proposed AD by August 27, 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 
                        ( print page 32216)
                        p.m., Monday through Friday, except Federal holidays. For service information identified in this NPRM, contact Bombardier, Inc., 400 Côte-Vertu Road West, Dorval, Québec H4S 1Y9, Canada; Widebody Customer Response Center North America toll-free telephone 866-538-1247 or direct-dial telephone 514-855-2999; fax 514-855-7401; email 
                        *ac.yul@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. 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-2018-0634; 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 regulatory evaluation, any comments received, and other information. The street address for Docket Operations (phone: 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; email 
                        *9-avs-nyaco-cos@faa.gov*.


SUPPLEMENTARY INFORMATION: Comments Invited We invite you to send any written relevant data, views, or arguments about this proposal. Send your comments to an address listed under the 
                    **ADDRESSES**
                     section. Include “Docket No. FAA-2018-0634; Product Identifier 2018-NM-050-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this NPRM. We will consider all comments received by the closing date and may amend this NPRM because of 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 NPRM. Discussion Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued Canadian AD CF-2018-02, dated January 16, 2018 (referred to after this as the Mandatory Continuing Airworthiness Information, or “the MCAI”), to correct an unsafe condition for certain Bombardier, Inc., Model CL-600-2C10 (Regional Jet Series 700, 701 & 702) airplanes, Model CL-600-2D15 (Regional Jet Series 705) airplanes, Model CL-600-2D24 (Regional Jet Series 900) airplanes, and Model CL-600-2E25 (Regional Jet Series 1000) airplanes. The MCAI states: Five cases of fractured Main Landing Gear (MLG) Orifice Support Tube (OST) have been reported. Subsequent analysis determined that the MLG OST is unable to withstand the loads generated during a hard landing event. A MLG OST fracture cannot be detected during routine maintenance and if not corrected, a fractured MLG OST can lead to aeroplane structural damage and/or collapse of the MLG. This [Canadian] AD mandates the replacement of the existing MLG OSTs with a re-designed part, and the implementation of a new airworthiness limitation task. 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-2018-0634. Related Service Information Under 1 CFR Part 51 Bombardier has issued Service Bulletin SB 670BA-32-058, dated September 26, 2016. The service information describes procedures for replacing each MLG OST. Bombardier has also issued Temporary Revision ALI-0593, dated December 18, 2017. The service information describes new life limits for the MLG OSTs. These service information are 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 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 the relevant information and determined the unsafe condition described previously is likely to exist or develop on other products of the same type design. This AD requires revisions to certain operator maintenance documents to include new actions (
                    *e.g.,*
                     inspections). Compliance with these actions is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by this proposed AD, the operator may not be able to accomplish the actions described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request approval for an alternative method of compliance according to paragraph (i) of this proposed AD. The request should include a description of changes to the required actions that will ensure the continued damage tolerance of the affected structure. Proposed AD Requirements This proposed AD would require replacing the MLG OST and revising the maintenance or inspection program, as applicable, to incorporate new or more restrictive maintenance requirements and airworthiness limitations. Costs of Compliance We estimate that this proposed AD affects 542 airplanes of U.S. registry. We estimate the following costs to comply with this proposed AD: Estimated Costs
Action
Labor cost
Parts cost
Cost per 
                             product
Cost on U.S. 
                             operatorsReplacement (left- and right-hand sides)
24 work-hours × $85 per hour = $2,040
* $0
$2,040
$1,105,680* We have received no definitive data that would enable us to provide cost estimates for the parts cost in this AD.
 We have determined that revising the maintenance or inspection program takes an average of 90 work-hours per operator, although we recognize that this number may vary from operator to operator. In the past, we have estimated 
                    ( print page 32217)
                    that this action takes 1 work-hour per airplane. Since operators incorporate maintenance or inspection program changes for their affected fleet(s), we have determined that a per-operator estimate is more accurate than a per-airplane estimate. Therefore, we estimate the total cost per operator to be $7,650 (90 work-hours × $85 per work-hour). 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 proposed 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 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
 2.The FAA amends § 39.13 by adding the following new airworthiness directive (AD): **Bombardier, Inc.:**
                         Docket No. FAA-2018-0634; Product Identifier 2018-NM-050-AD. (a) Comments Due Date We must receive comments by August 27, 2018. (b) Affected ADs None. (c) Applicability This AD applies to the Bombardier, Inc., airplanes specified in paragraphs (c)(1), (c)(2), and (c)(3) of this AD, certificated in any category. (1) Model CL-600-2C10 (Regional Jet Series 700, 701 & 702) airplanes, serial numbers 10003 through 10345 inclusive. (2) Model CL-600-2D15 (Regional Jet Series 705) airplanes and Model CL-600-2D24 (Regional Jet Series 900) airplanes, serial numbers 15001 through 15429 inclusive. (3) Model CL-600-2E25 (Regional Jet Series 1000) airplanes, serial numbers 19001 through 19052 inclusive. (d) Subject Air Transport Association (ATA) of America Code 32, Main landing gear. (e) Reason This AD was prompted by reports of a fractured main landing gear (MLG) orifice support tube (OST). We are issuing this AD to address a fractured MLG OST, which can lead to structural damage to the airplane and collapse of the MLG. (f) Compliance Comply with this AD within the compliance times specified, unless already done. (g) Replacement Within the compliance times specified in figure 1 to paragraph (g) of this AD: Replace each MLG OST, in accordance with the Accomplishment Instructions of Bombardier Service Bulletin SB 670BA-32-058, dated September 26, 2016. 
 
  (h) Maintenance or Inspection Program Revision Within 90 days after the effective date of this AD, revise the maintenance or inspection program, as applicable, to incorporate Bombardier Temporary Revision ALI-0593, dated December 18, 2017. The initial compliance time for accomplishing the actions is at the applicable time specified in Bombardier Temporary Revision ALI-0593, dated December 18, 2017; or within 90 days after the effective date of this AD; whichever occurs later. (i) No Alternative Actions or Intervals After the maintenance or inspection program has been revised as required by paragraph (h) of this AD, no alternative actions (
                        *e.g.,*
                         inspections) or intervals may be used unless the actions or intervals are approved as an alternative method of compliance (AMOC) in accordance with the procedures specified in paragraph (j)(1) of this AD. (j) 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 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. 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. (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. (k) Related Information (1) Refer to Mandatory Continuing Airworthiness Information (MCAI) Canadian AD CF-2018-02, dated January 16, 2018, 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-2018-0634. (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; email 
                        *9-avs-nyaco-cos@faa.gov.* (3) For service information identified in this AD, contact Bombardier, Inc., 400 Côte-Vertu Road West, Dorval, Québec H4S 1Y9, Canada; Widebody Customer Response Center North America toll-free telephone 866-538-1247 or direct-dial telephone 514-855-2999; fax 514-855-7401; email 
                        *ac.yul@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 Des Moines, Washington, on July 3, 2018. Michael Kaszycki, Acting Director, System Oversight Division, Aircraft Certification Service.


[FR Doc. 2018-14804 Filed 7-11-18; 8:45 am] BILLING CODE 4910-13-P