DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0028; Product Identifier 2017-NM-143-AD; Amendment
39-19356; AD 2018-17-02]
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-600-1A11 (600), CL-600-2A12 (601), and CL-
600-2B16 (601-3A, 601-3R, and 604 Variants) airplanes. This AD was
prompted by a determination that the safe life limits of the horizontal
stabilizer trim actuator (HSTA) attachment pins and trunnions were not
listed in certain airworthiness limitations (AWLs) and that the HSTA
attachment pins and trunnions were not serialized. This AD requires
revision of the maintenance or inspection program, as applicable, to
include the latest revision of the AWLs, serialization of the HSTA
attachment pins and trunnions, and repair or replacement of damaged
HSTA attachment pins and
trunnions. We are issuing this AD to address the unsafe condition on
these products.

DATES: This AD is effective September 19, 2018.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of September 19,
2018.

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 1-866-538-1247 or direct-dial telephone 1-
514-855-2999; fax 514-855-7401; email ac.yul@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. It is also available on the
internet at http://www.regulations.gov by searching for and locating
Docket No. FAA-2018-0028.

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-
0028; 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 AD, the regulatory evaluation, any comments received, and
other information. The street address for the Docket Office (telephone
800-647-5527) is Docket Management Facility, 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 516-228-7239;
fax 516-794-5531; email 9-avs-nyaco-cos@faa.gov.

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-600-1A11 (600), CL-600-2A12 (601), and CL-600-2B16 (601-3A,
601-3R, and 604 Variants) airplanes. The NPRM published in the Federal
Register on February 8, 2018 (83 FR 5587) (``the NPRM''). The NPRM was
prompted by a determination that the safe life limits of the HSTA
attachment pins and trunnions were not listed in certain AWLs and that
the HSTA attachment pins and trunnions were not serialized. The NPRM
proposed to require revision of the maintenance or inspection program,
as applicable, to include the latest revision of the AWLs,
serialization of the HSTA attachment pins and trunnions, and repair or
replacement of damaged HSTA attachment pins and trunnions. We are
issuing this AD to address failure of the HSTA attachment pins and
trunnions, which could lead to a disconnect of the horizontal
stabilizer and subsequent loss of the airplane.
Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian AD CF-2017-24, dated July 12,
2017 (referred to after this as the Mandatory Continuing Airworthiness
Information, or ``the MCAI''), to correct an unsafe condition for
certain Bombardier, Inc., Model CL-600-1A11 (600), CL-600-2A12 (601),
and CL-600-2B16 (601-3A, 601-3R, and 604 Variants) airplanes. The MCAI
states:

During a review of the Horizontal Stabilizer Trim Actuator
(HSTA) system, it was discovered that the safe life limits of the
HSTA attachment pins and trunnions were not listed in the
Airworthiness Limitation (AWL) Section of the Instructions for
Continued Airworthiness. Also, the HSTA attachment pins and
trunnions were not serialized making it impossible to keep accurate
records of the life of these parts. Failure of these pins and
trunnions could lead to a disconnect of the horizontal stabilizer
and subsequent loss of the aeroplane.
This [Canadian] AD mandates the incorporation of AWL tasks into
the maintenance schedule and serialization of HSTA attachment pins
and trunnions. Some aircraft require AWL tasks and serialization of
the attachment pins only, while others require AWL tasks and
serialization of the trunnions and attachment pins [and repair or
replacement if damaged (including linear scratches, pits, spalling,
dents, or surface texture variations)].

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-
0028.

Comments

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

Request To Allow Using Later Revisions of the Service Information

NetJets requested that paragraph (h) of the proposed AD be revised
to specify the latest time limits/maintenance checks (TLMC) revisions.
NetJets noted that some of the TLMC documents referenced in the
proposed AD have been revised. NetJets also requested that we revise
the proposed AD so that operators can use later approved revisions of
the TLMC documents to show compliance without requesting an alternative
method of compliance (AMOC).
We partially agree with the commenter's request. In this
circumstance, the specific tasks required by this AD have not changed
in the latest available service information from the earlier revisions
of the service information specified in the NPRM. We have therefore
revised this AD to refer to the latest available service information
and revised paragraph (k) of this AD to provide credit for actions done
using earlier revisions of certain service information. However, we may
not refer to any document that does not yet exist. In general terms, we
are required by Office of the Federal Register (OFR) regulations to
either publish the service document contents as part of the actual AD
language; or submit the service document to the OFR for approval as
``referenced'' material, in which case we may only refer to such
material in the text of an AD. The AD may refer to the service document
only if the OFR approved it for ``incorporation by reference.'' See 1
CFR part 51.
To allow operators to use later revisions of the referenced
document (issued after publication of the AD), either we must revise
the AD to reference specific later revisions, or operators must request
approval to use later revisions as an AMOC with this AD under the
provisions of paragraph (m)(1) of this AD. We cannot reference a
specific revision not yet in existence so the only option is to request
an AMOC.

Request To Use a Service Bulletin Instead of a TLMC

Disney Aviation Group requested that the proposed AD be revised to
use actions in a service bulletin instead of the TLMC for any required
inspections. The commenter noted that most operators have an electronic
subscription that automatically gives them the newest revision of the
TLMC documents. The commenter stated that since the TLMCs have been
updated since the draft AD was issued, operators
will not be able to comply with the AD, and will have to request an
AMOC. The commenter noted that service bulletins are not revised as
often as TLMC documents, and when they are updated they are not
superseded by future revisions. The commenter pointed out that other
manufacturers issue service bulletins with similar requirements and the
related ADs require those service bulletins.
We disagree with the commenter's request. As noted previously, we
have revised this AD to refer to the latest available TLMC documents.
We cannot, however, mandate how a given manufacturer makes their
service information available. Since Bombardier, Inc. has chosen to
provide the TLMCs in a separate document, rather than a service
bulletin, that is what operators must use to show compliance with this
AD. We have therefore not changed this AD in this regard.

Conclusion

We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this AD 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 correcting 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 AD.

Related Service Information Under 1 CFR Part 51

Bombardier has issued the following service information.
The following service information describes procedures for
serializing the HSTA attachment pins and trunnions. These documents are
distinct since they apply to different airplane models in different
configurations.
Bombardier Service Bulletin 600-0760, Revision 01, dated
April 21, 2017.
Bombardier Service Bulletin 601-0626, Revision 01, dated
April 21, 2017.
Bombardier Service Bulletin 604-27-034, Revision 01, dated
April 21, 2017.
Bombardier Service Bulletin 605-27-005, Revision 01, dated
April 21, 2017.
The following service information identifies airworthiness
limitation tasks for revising the life limits for HSTA attachment pins
and trunnions. These documents are distinct since they apply to
different airplane models in different configurations.
Section 5-10-10, ``Time Limits (Structural),'' of Section
5-10-00, ``Airworthiness Limitations,'' of Bombardier Challenger 600
Time Limits/Maintenance Checks, Publication No. PSP 605, Revision 39,
dated January 8, 2018.
Section 5-10-10, ``Time Limits (Structural)--Pre SB 601-
0280,'' of Section 5-10-00, ``Airworthiness Limitations,'' of
Bombardier Challenger 601 Time Limits/Maintenance Checks, Publication
No. PSP 601-5, Revision 46, dated January 8, 2018.
Section 5-10-11, ``Time Limits (Structural)--Post SB 601-
0280,'' of Section 5-10-00, ``Airworthiness Limitations,'' of
Bombardier Challenger 601 Time Limits/Maintenance Checks, Publication
No. PSP 601-5, Revision 46, dated January 8, 2018.
Section 5-10-12, ``Time Limits (Structural)--Post SB 601-
0360,'' of Section 5-10-00, ``Airworthiness Limitations,'' of
Bombardier Challenger 601 Time Limits/Maintenance Checks, Publication
No. PSP 601-5, Revision 46, dated January 8, 2018.
Section 5-10-10, ``Time Limits (Structural),'' of Section
5-10-00, ``Airworthiness Limitations,'' of Bombardier Challenger 601
Time Limits/Maintenance Checks, Publication No. PSP 601A-5, Revision
42, dated January 8, 2018.
Section 5-10-11, ``Time Limits (Structural),'' of Section
5-10-00, ``Airworthiness Limitations,'' of Bombardier Challenger 601
Time Limits/Maintenance Checks, Publication No. PSP 601A-5, Revision
42, dated January 8, 2018.
Section 5-10-12, ``Time Limits (Structural),'' of Section
5-10-00, ``Airworthiness Limitations,'' of Bombardier Challenger 601
Time Limits/Maintenance Checks, Publication No. PSP 601A-5, Revision
42, dated January 8, 2018.
The following service information describes life limits for certain
HSTA attachment pins and trunnion supports. These documents are
distinct since they apply to different airplane models in different
configurations.
Section 5-10-10, ``Life Limits (Structures),'' of
Bombardier Challenger 604 CL-604 Time Limits/Maintenance Checks, Part 2
Airworthiness Limitations, Revision 30, dated December 4, 2017. This
service information describes, among other tasks: Task 27-42-01-108,
``Discard of the Horizontal-Stabilizer Trim-Actuator (HSTA) Trunnion
Support; Part No. 601R92386-1/-3;'' and Task 27-42-01-112, ``Discard of
the Horizontal-Stabilizer Trim-Actuator (HSTA) Upper and Lower
Attachment Pins; Upper Pin Part No. 600-92384-5/-7 or 601R92310-1/-3
and Lower Pin Part No. 600-92383-5/-7 or 601R92309-1/-3.''
Section 5-10-10, ``Life Limits (Structures),'' of
Bombardier Challenger 605 CL-605 Time Limits/Maintenance Checks, Part 2
Airworthiness Limitations, Revision 18, dated December 4, 2017. This
service information describes, among other tasks: Task 27-42-01-108,
``Discard of the Horizontal-Stabilizer Trim-Actuator (HSTA) Trunnion
Support; Part No. 601R92386-1/-3;'' and Task 27-42-01-112, ``Discard of
the Horizontal-Stabilizer Trim-Actuator (HSTA) Upper and Lower
Attachment Pins; Upper Pin Part No. 600-92384-5/-7 or 601R92310-1/-3
and Lower Pin Part No. 600-92383-5/-7 or 601R92309-1/ -3.''
Section 5-10-10, ``Life Limits (Structures),'' of
Bombardier Challenger 650 CL-650 Time Limits/Maintenance Checks, Part 2
Airworthiness Limitations, Revision 5, dated December 4, 2017. This
service information describes, among other tasks: Task 27-42-01-108,
``Discard of the Horizontal-Stabilizer Trim-Actuator (HSTA) Trunnion
Support; Part No. 601R92386-1/-3;'' and Task 27-42-01-112, ``Discard of
the Horizontal-Stabilizer Trim-Actuator (HSTA) Upper and Lower
Attachment Pins; Upper Pin Part No. 600-92384-5/-7 or 601R92310-1/-3
and Lower Pin Part No. 600-92383-5/-7 or 601R92309-1/-3.''
The following service information describes procedures for
identifying damage to HSTA attachment pins and trunnions, and repair or
replacement instructions. These documents are distinct since they apply
to different airplane models in different configurations.
Bombardier Repair Engineering Order (REO) 600-27-42-002,
``General Repair--HSTA Upper and Lower Pins,'' dated December 15, 2016.
Bombardier Repair Engineering Order (REO) 604-27-42-011,
``General Repair--HSTA Trunnion P/N 601R92386-1/-3,'' dated December
15, 2016.
Bombardier Repair Engineering Order (REO) 604-27-42-012,
``General Repair--HSTA Upper and Lower Pins,'' dated December 15, 2016.
This service information is reasonably available because the
interested parties have access to it through their normal course of
business or by the means identified in the ADDRESSES section.

Costs of Compliance

We estimate that this AD affects 137 airplanes of U.S. registry. We
estimate the following costs to comply with this AD:

Estimated Costs for Required Actions

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

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]

2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):