Document ID: FAA-2018-0634-0008
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Bombardier, Inc., Airplanes
Posted Date: 2019-03-29T04:00Z

[Federal Register Volume 84, Number 61 (Friday, March 29, 2019)]
[Rules and Regulations]
[Pages 11880-11884]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-06029]

[[Page 11880]]

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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; Amendment 
39-19594; AD 2019-05-12]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

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

ACTION: Final rule.

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SUMMARY: We are adopting 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 AD was prompted by 
reports of a fractured main landing gear (MLG) orifice support tube 
(OST). This AD requires replacing the MLG OST, and revising the 
existing maintenance or inspection program, as applicable, to 
incorporate new or more restrictive maintenance requirements and 
airworthiness limitations. We are issuing this AD to address the unsafe 
condition on these products.

DATES: This AD is effective May 3, 2019.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of May 3, 2019.

ADDRESSES: For service information identified in this final rule, 
contact Bombardier, Inc., 400 C[ocirc]te Vertu Road West, Dorval, 
Qu[eacute]bec 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 [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. It is also available on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
0634.

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 final rule, the regulatory evaluation, any comments received, and 
other information. The address for Docket Operations (phone: 800-647-
5527) 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: 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 [email protected].

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 by adding an AD that would apply to 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 NPRM published in the Federal Register 
on July 12, 2018 (83 FR 32215). The NPRM was prompted by reports of a 
fractured MLG OST. The NPRM proposed to require replacing the MLG OST, 
and revising the existing maintenance or inspection program, as 
applicable, to incorporate new or more restrictive maintenance 
requirements and airworthiness limitations.
    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.
    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.

Comments

    We gave the public the opportunity to participate in developing 
this final rule. The following presents the comments received on the 
NPRM and the FAA's response to each comment.

Support for the NPRM

    The Air Line Pilots Association, International (ALPA), and Endeavor 
Air stated their support for the NPRM.

Request To Refer to Revised Service Information

    Bombardier stated that Bombardier Service Bulletin 670BA-32-058, 
dated September 26, 2016, was being revised to include procedures for 
on-wing replacement of the MLG OSTs. This service bulletin was referred 
to as the required source of service information for accomplishing the 
replacement of the MLG OSTs in the proposed AD. The commenter stated 
that it estimated that Bombardier Service Bulletin 670BA-32-058, 
Revision A, would be released in October of 2018.
    We infer that the commenter is requesting that this AD refer to 
Bombardier Service Bulletin 670BA-32-058, Revision A, as the required 
source of service information for replacing the MLG OSTs. We agree with 
the commenter's request. We have included Bombardier Service Bulletin 
670BA-32-058, Revision A, dated November 7, 2018, in this AD. 
Bombardier Service Bulletin 670BA-32-058, Revision A, dated November 7, 
2018, adds an optional procedure for OST installation. We have 
determined that no additional work is required for airplanes that have 
accomplished the actions specified in Bombardier Service Bulletin 
670BA-32-058, dated September 26, 2016. We have added paragraph (j) to 
this AD to provide credit for actions done before the effective date of 
this AD using Bombardier Service Bulletin 670BA-32-058, dated September 
26, 2016. We have also redesignated the subsequent paragraphs 
accordingly.

[[Page 11881]]

Request To Clarify Applicability

    Envoy Air requested that the applicability of the proposed AD be 
clarified by including the MLG shock strut assemblies part numbers (P/
Ns) 49200-9 through 49200-32 with orifice OSTs installed having P/N 
49212-3 or 49212-5. The commenter stated that it perceived the intent 
of the proposed AD was to address the unsafe condition by replacing in-
service OSTs with re-designed OSTs having P/N 49212-7 or 49212-9. The 
commenter observed that OSTs with P/Ns 49212-3 and 49212-5 are not 
tracked, however, the MLG shock strut assemblies on which the OSTs are 
installed, are tracked.
    The commenter explained that the MLG shock strut assemblies on 
which OSTs are installed can be replaced in the field and can be moved 
among airplanes and operators. The commenter suggested that changing 
the applicability to include the part numbers of the MLG shock strut 
assemblies and OSTs would allow operators to track the affected OSTs 
regardless of where they are installed.
    We acknowledge the commenter's request and agree to clarify. 
Section 1.A., ``Effectivity,'' of Bombardier Service Bulletin 670BA-32-
058, Revision A, dated November 7, 2018, provides the part numbers and 
serial numbers of the affected MLG shock strut assemblies on which the 
affected OSTs were installed, and the serial numbers of the airplanes 
on which the MLG shock strut assemblies were installed when the 
airplane was delivered. We recognize that the affected OSTs are not 
easily tracked. Therefore, we have revised figure 1 to paragraph (g) of 
this AD to clarify the compliance times by referring to the MLG shock 
strut assembly instead of the OST. However, we do not agree to revise 
the applicability of this AD, which corresponds with the applicability 
of the corresponding Canadian AD. We have coordinated this issue with 
Bombardier and determined that the applicability is acceptable. There 
is minimal risk for rotation of affected OSTs and expanding the 
applicability would require a Supplemental NPRM for additional public 
comments, which would further delay issuance of this AD. Therefore, we 
have not changed this AD in regard to this issue.

Request To Revise Proposed Compliance Time

    Bombardier and Endeavor Air requested that the compliance times in 
paragraph (g) of the proposed AD be changed to the number of total 
flight cycles accumulated on the MLG shock strut assembly since it was 
new instead of the number of total flight cycles accumulated on the MLG 
OSTs. Both of the commenters noted that OSTs having P/Ns 49212-3 and 
49212-5 are not tracked, however, flight cycles are tracked for the MLG 
shock strut assemblies on which the OSTs are installed. Endeavor Air 
stated that operators cannot comply with the proposed compliance times 
because the OSTs are not tracked and operators would not know when the 
OSTs have reached the flight cycle limits specified in paragraph (g) of 
the proposed AD. Endeavor Air noted that, because the OST is internal 
to the MLG shock strut assembly, MLG shock strut assemblies that have 
not been overhauled will have OSTs with the same flight cycle 
accumulation as the MLG shock strut assembly, and if an OST had been 
replaced it would have been replaced with a new OST having fewer flight 
cycles than the MLG shock strut assembly it is installed on. Therefore, 
it is unlikely the OST would have accumulated more flight cycles than 
the MLG shock strut assembly on which it is installed. Bombardier noted 
that, when an OST is removed during repair or overhaul of the MLG shock 
strut assembly, it will remain with the MLG shock strut assembly when 
it is returned to service.
    We agree with the commenters' requests. Operators can use the total 
flight cycles on the MLG shock strut assembly since new, but not since 
overhaul, to determine the applicable compliance time. If an MLG shock 
strut assembly is overhauled and the OST is removed, if it is a 
serviceable OST, it will typically be re-installed on the overhauled 
MLG shock strut assembly. We have revised figure 1 to paragraph (g) of 
this AD to clarify the compliance times.

Request To Allow Replacement of OSTs Using Alternative Methods

    Endeavor Air requested that the proposed AD allow approval and 
credit for replacement of OSTs using methods other than following the 
procedures in Bombardier Service Bulletin 670BA-32-058, dated September 
26, 2016. The commenter stated that operators might have replaced 
affected OSTs after a non-routine event or after sending an MLG shock 
strut assembly out for repair or overhaul. The commenter noted that 
Bombardier has issued Reference Instruction Letter (RIL) 5096, Revision 
C, dated June 20, 2017, for replacement of OSTs after a suspected hard 
landing. The commenter noted that the Bombardier RIL refers to the same 
vendor service information that is specified in Bombardier Service 
Bulletin 670BA-32-058, dated September 26, 2016, for accomplishing 
replacement of the OSTs. The commenter specifically requested that 
paragraph (g) of the proposed AD be revised, or a new paragraph 
created, to provide credit for MLG shock strut assemblies that have new 
OSTs installed using the Bombardier RIL, the applicable vendor service 
information, or the applicable vendor component maintenance manual. The 
commenter noted that maintenance repair organizations will replace OSTs 
using the applicable vendor service bulletin and not Bombardier Service 
Bulletin 670BA-32-058, dated September 26, 2016.
    We do not agree with the commenter's request. We contacted 
Bombardier and Bombardier stated that the Bombardier RIL provides 
procedures for replacing an OST following a high-load landing, and does 
not specify that the replacement OSTs must have P/N 49212-7 or 49212-9. 
In addition, Bombardier Service Bulletin 670BA-32-058, dated September 
26, 2016, includes certain leak checks that must be done; those leak 
checks are not specified in the Bombardier RIL. We have not changed 
this AD in regard to this issue.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
this final rule with the changes described previously and minor 
editorial changes. We have 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.
    We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of this final 
rule.

Related Service Information Under 1 CFR Part 51

    Bombardier has issued Service Bulletin 670BA-32-058, Revision A, 
dated November 7, 2018. The service information describes procedures 
for replacing each MLG OST.
    Bombardier has also issued CRJ700/900/1000 Airworthiness 
Limitations Temporary Revision ALI-0593, dated December 18, 2017. The 
service information describes new life limits for the MLG OSTs.
    This service information is reasonably available because the 
interested parties

[[Page 11882]]

have access to it through their normal course of business or by the 
means identified in the ADDRESSES section.

Costs of Compliance

    We estimate that this AD affects 542 airplanes of U.S. registry. We 
estimate the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Replacement (left- and right-hand       24 work-hours x $85 per           \*\ $0          $2,040      $1,105,680
 sides).                                 hour = $2,040.
----------------------------------------------------------------------------------------------------------------
* 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 existing 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 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 x $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 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 and 
associated appliances to the Director of the System Oversight Division.

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) 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.

Adoption of 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

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 adding the following new airworthiness 
directive (AD):

2019-05-12 Bombardier, Inc.: Amendment 39-19594; Docket No. FAA-
2018-0634; Product Identifier 2018-NM-050-AD.

(a) Effective Date

    This AD is effective May 3, 2019.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to the Bombardier, Inc., airplanes identified 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, 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 670BA-32-
058, Revision A, dated November 7, 2018.
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[GRAPHIC] [TIFF OMITTED] TR29MR19.000

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(h) Maintenance or Inspection Program Revision

    Within 90 days after the effective date of this AD, revise the 
existing maintenance or inspection program, as applicable, to 
incorporate Bombardier CRJ700/900/1000 Airworthiness Limitations 
Temporary Revision ALI-0593, dated December 18, 2017. The initial 
compliance time for accomplishing the actions is at the applicable 
time specified in Bombardier CRJ700/900/1000 Airworthiness 
Limitations 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 existing 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 (k)(1) of this AD.

(j) Credit for Previous Actions

    This paragraph provides credit for the actions specified in 
paragraph (g) of this AD, if those actions were performed before the 
effective date of this AD using Bombardier Service Bulletin 670BA-
32-058, dated September 26, 2016.

(k) 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.

(l) 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 [email protected].
    (3) Service information identified in this AD that is not 
incorporated by reference is available at the addresses specified in 
paragraphs (m)(3) and (m)(4) of this AD.

(m) 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) Bombardier Service Bulletin 670BA-32-058, Revision A, dated 
November 7, 2018.

[[Page 11884]]

    (ii) Bombardier CRJ700/900/1000 Airworthiness Limitations 
Temporary Revision ALI-0593, dated December 18, 2017.
    (3) For service information identified in this AD, contact 
Bombardier, Inc., 400 C[ocirc]te-Vertu Road West, Dorval, 
Qu[eacute]bec 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 
[email protected]; internet http://www.bombardier.com.
    (4) 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.
    (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, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued in Des Moines, Washington, on March 20, 2019.
Michael Kaszycki,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2019-06029 Filed 3-28-19; 8:45 am]
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