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

ACTION: Final rule.

SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Bombardier, Inc. Model DHC-8-102, -103, -106, -201, -202, -301, -311,
and -315 airplanes. This AD was prompted by reports of a fractured
wing-to-fuselage strut attachment joint bolt. This AD requires a torque
check of all wing-to-fuselage strut attachment joint bolts, and repair
or replacement if necessary. For certain airplanes, this AD also
requires a detailed inspection for corrosion, damage, and wear of each
wing-to-fuselage strut attachment joint bolt and associated hardware,
and replacement if necessary; and a borescope inspection for corrosion
and damage of the bore hole and barrel nut threads, and repair or
replacement if necessary. We are issuing this AD to detect and correct
fractured strut attachment joint bolts, which could result in reduced
structural integrity of the wing-to-fuselage strut attachment joint and
subsequent loss of the wing.

DATES: This AD becomes effective September 2, 2014.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of September 2,
2014.

ADDRESSES: You may examine the AD docket on the Internet at http://www.regulations.gov/#!documentDetail;D=FAA-2013-1024-
0002 or in person at the 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.
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 referenced service information at
the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton,
WA. For information on the availability of this material at the FAA,
call 425-227-1221.

FOR FURTHER INFORMATION CONTACT: Jeffrey Zimmer, Aerospace Engineer,
Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, NY
11590; telephone (516) 228-7306; fax (516) 794-5531.

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 DHC-8-102, -103, -106, -201, -202, -301, -311, and -315
airplanes. The NPRM published in the Federal Register on December 6,
2013 (78 FR 73462).
Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued Canadian Airworthiness Directive CF-
2013-17R1, dated June 27, 2013 (referred to after this as the Mandatory
Continuing Airworthiness Information, or ``the MCAI''), to correct an
unsafe condition for certain Bombardier, Inc. Model DHC-8-102, -103, -
106, -201, -202, -301, -311, and -315 airplanes. The MCAI states:

There have been two in-service reports of a wing-to-fuselage
strut attachment joint bolt found fractured during routine
maintenance. Laboratory examination of one fractured bolt revealed
that the fracture was attributed to stress corrosion cracking.
Failure of the bolts could compromise the structural integrity
of the wing-to-fuselage strut attachment joint and could lead to a
subsequent loss of the wing.
This [Canadian] AD mandates the inspection and rectification, as
required, of the wing-to-fuselage strut attachment joint bolts and
associated hardware.
* * * * *
Required actions include a torque check of wing-to-fuselage strut
attachment joint bolts, and repair or replacement if necessary. For
certain airplanes, required actions include a detailed inspection for
corrosion, damage (including but not limited to scratching, cracking,
pitting, cross threads), and wear of each wing-to-fuselage strut
attachment joint bolt and associated hardware, and replacement if
necessary; and a borescope inspection for corrosion and damage of the
bore hole and barrel nut threads, and repair or replacement if
necessary. You may examine the MCAI in the AD docket on the Internet at
http://www.regulations.gov/#!documentDetail;D=FAA-2013-1024-0002.

Comments

We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the NPRM (78
FR 73462, December 6, 2013) and the FAA's response to each comment.

Request To Extend Compliance Time

An anonymous commenter requested that we extend the compliance
times from 2,000 flight cycles or 12 months, to 4,000 flight cycles or
24 months, after the effective date of the AD, in order to coincide
with their scheduled ``C'' checks.
We do not agree with the commenter's request to extend the
compliance time. We have determined that the compliance time, as
proposed, represents the maximum interval of time allowable for the
affected airplanes to continue to safely operate before the
modification is done. We have not changed this AD in this regard.

Request To Give Credit for Previous Compliance

An anonymous commenter requested that we allow credit for actions
accomplished using deHavilland Dash 8 Series 100 Task Card Number 5730/
04B, dated February 6, 2012, if the actions were done before the date
the final rule becomes effective.
We agree with the request. We have redesignated paragraph (j) of
the proposed AD (78 FR 73462, December 6, 2013) as paragraph (j)(1) of
this AD, and have added new paragraph (j)(2) to this AD to allow credit
for actions accomplished prior to the effective date of this AD using
deHavilland Dash 8 Series 100 Task Card Number 5730/04B, dated February
6, 2012.

"Contacting the Manufacturer" Paragraph in This AD

Since late 2006, we have included a standard paragraph titled
``Airworthy Product'' in all MCAI ADs in which the FAA develops an AD
based on a foreign authority's AD.
The MCAI or referenced service information in an FAA AD often
directs the owner/operator to contact the manufacturer for corrective
actions, such as a repair. Briefly, the Airworthy Product paragraph
allowed owners/operators to use corrective actions provided by the
manufacturer if those actions were FAA-approved. In addition, the
paragraph stated that any actions approved by the State of Design
Authority (or its delegated agent) are considered to be FAA-approved.
In the NPRM (78 FR 73462, December 6, 2013), we proposed to prevent
the use of repairs that were not specifically developed to correct the
unsafe condition, by requiring that the repair approval provided by the
State of Design Authority or its delegated agent specifically refer to
this FAA AD. This change was intended to clarify the method of
compliance and to provide operators with better visibility of repairs
that are specifically developed and approved to correct the unsafe
condition. In addition, proposed to change the phrase ``its delegated
agent'' to include a design approval holder (DAH) with State of Design
Authority design organization approval (DOA), as applicable, to refer
to a DAH authorized to approve required repairs for the NPRM.
No comments were provided to the NPRM (78 FR 73462, December 6,
2013) about these proposed changes. However, a comment was provided for
an NPRM having Directorate Identifier 2012-NM-101-AD (78 FR 78285,
December 26, 2013). The commenter stated the following: ``The proposed
wording, being specific to repairs, eliminates the interpretation that
Airbus messages are acceptable for approving minor deviations
(corrective actions) needed during accomplishment of an AD mandated
Airbus service bulletin.''
This comment has made the FAA aware that some operators have
misunderstood or misinterpreted the Airworthy Product paragraph to
allow the owner/operator to use messages provided by the manufacturer
as approval of deviations during the accomplishment of an AD-mandated
action. The Airworthy Product paragraph does not approve messages or
other information provided by the manufacturer for deviations to the
requirements of the AD-mandated actions. The Airworthy Product
paragraph only addresses the requirement to contact the manufacturer
for corrective actions for the identified unsafe condition and does not
cover deviations from other AD requirements.

However, deviations to AD-required actions are addressed in 14 CFR
39.17, and anyone may request the approval for an alternative method of
compliance to the AD-required actions using the procedures found in 14
CFR 39.19.
To address this misunderstanding and misinterpretation of the
Airworthy Product paragraph, we have changed the paragraph and retitled
it ``Contacting the Manufacturer.'' This paragraph now clarifies that
for any requirement in this AD to obtain corrective actions from a
manufacturer, the action must be accomplished using a method approved
by the FAA, TCCA, or Bombardier's TCCA Design Approval Organization
(DAO).
The Contacting the Manufacturer paragraph also clarifies that, if
approved by the DAO, the approval must include the DAO-authorized
signature. The DAO signature indicates that the data and information
contained in the document are TCCA-approved, which is also FAA-
approved. Messages and other information provided by the manufacturer
that do not contain the DAO-authorized signature approval are not TCCA-
approved, unless TCCA directly approves the manufacturer's message or
other information.
This clarification does not remove flexibility previously afforded
by the Airworthy Product paragraph. Consistent with long-standing FAA
policy, such flexibility was never intended for required actions. This
is also consistent with the recommendation of the Airworthiness
Directive Implementation Aviation Rulemaking Committee to increase
flexibility in complying with ADs by identifying those actions in
manufacturers' service instructions that are ``Required for
Compliance'' with ADs. We continue to work with manufacturers to
implement this recommendation. But once we determine that an action is
required, any deviation from the requirement must be approved as an
alternative method of compliance.
Other commenters to the NPRM having Directorate Identifier 2012-NM-
101-AD (78 FR 78285, December 26, 2013) pointed out that in many cases
the foreign manufacturer's service bulletin and the foreign authority's
MCAI might have been issued some time before the FAA AD. Therefore, the
DOA might have provided U.S. operators with an approved repair,
developed with full awareness of the unsafe condition, before the FAA
AD is issued. Under these circumstances, to comply with the FAA AD, the
operator would be required to go back to the manufacturer's DOA and
obtain a new approval document, adding time and expense to the
compliance process with no safety benefit.
Based on these comments, we removed the requirement that the DAH-
provided repair specifically refer to this AD. Before adopting such a
requirement, the FAA will coordinate with affected DAHs and verify they
are prepared to implement means to ensure that their repair approvals
consider the unsafe condition addressed in this AD. Any such
requirements will be adopted through the normal AD rulemaking process,
including notice-and-comment procedures, when appropriate. We also have
decided not to include a generic reference to either the ``delegated
agent'' or ``DAH with State of Design Authority design organization
approval,'' but instead we have provided the specific delegation
approval granted by the State of Design Authority for the DAH
throughout this AD.

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 (78 FR 73462, December 6, 2013) for correcting the unsafe
condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM (78 FR 73462, December 6, 2013).
We also determined that these changes will not increase the
economic burden on any operator or increase the scope of this AD.

Costs of Compliance

We estimate that this AD affects 94 airplanes of U.S. registry. We
estimate the following costs to comply with this AD.
We also estimate that it would take about 107 work-hours per
product to comply with the basic requirements of this AD. The average
labor rate is $85 per work-hour. Required parts would cost about $5,476
per product. Based on these figures, we estimate the cost of this AD on
U.S. operators to be $1,369,674, or $14,571 per product.
We have received no definitive data that would enable us to provide
a cost estimate for the repairs or replacements 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.

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.

Examining the AD Docket

You may examine the AD docket on the Internet at http://www.regulations.gov/#!docketDetail;D=FAA-2013-1024; 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 Operations office (telephone 800-647-
5527) is in the ADDRESSES section.

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):