
[Federal Register Volume 78, Number 247 (Tuesday, December 24, 2013)]
[Proposed Rules]
[Pages 77615-77618]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-30468]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-1029; Directorate Identifier 2013-NM-177-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) 2010-13-
04, which applies to certain Bombardier, Inc. Model DHC-8-400 series 
airplanes. AD 2010-13-04 requires modifying the nose landing gear (NLG) 
trailing arm. Since we issued AD 2010-13-04, we received a report of 
several missing or damaged pivot pin retention bolts. This proposed AD 
would require installing a new pivot pin retention mechanism. This 
proposed AD would also add airplanes to the applicability. We are 
proposing this AD to prevent failure of the pivot pin retention bolt, 
which could result in a

[[Page 77616]]

loss of directional control or loss of a NLG tire during take-off or 
landing.

DATES: We must receive comments on this proposed AD by February 7, 
2014.

ADDRESSES: You may send comments 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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
    For service information identified in this proposed 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 review copies of the 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.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the MCAI, 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: Ricardo Garcia, Aerospace Engineer, 
Airframe and Mechanical Systems Branch, ANE-171, FAA, New York Aircraft 
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New 
York 11590; telephone (516) 228-7331; 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-2013-1029; 
Directorate Identifier 2013-NM-177-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

    On June 10, 2010, we issued AD 2010-13-04, Amendment 39-16335 (75 
FR 35622, June 23, 2010). AD 2010-13-04 requires actions intended to 
address an unsafe condition on the products listed above.
    Since we issued AD 2010-13-04, Amendment 39-16335 (75 FR 35622, 
June 23, 2010), Transport Canada Civil Aviation (TCCA), which is the 
aviation authority for Canada, has issued Canadian Airworthiness 
Directive CF-2009-29R1, dated August 14, 2013 (referred to after this 
as the Mandatory Continuing Airworthiness Information, or ``the 
MCAI''), to correct an unsafe condition for the specified products. The 
MCAI states:

    Two in-service incidents have been reported on DHC-8 Series 400 
aircraft in which the nose landing gear (NLG) trailing arm pivot pin 
retention bolt (part number NAS6204-13D) was damaged. One incident 
involved the left hand NLG tire which ruptured on take-off. 
Investigation determined that the retention bolt failure was due to 
repeated contact of the castellated nut with the towing device 
including both the towbar and the towbarless rigs. The loss of the 
retention bolt allowed the pivot pin to migrate from its normal 
position and resulted in contact with and rupture of the tire. The 
loss of the pivot pin could compromise retention of the trailing arm 
and could result in a loss of directional control due to loss of 
nose wheel steering. The loss of an NLG tire or the loss of 
directional control could adversely affect the aircraft during take 
off or landing.
    To prevent the potential failure of the pivot pin retention 
bolt, Bombardier Aerospace has developed a modification which 
includes a new retention bolt, a reverse orientation of the 
retention bolt and a rework of the weight on wheel (WOW) proximity 
sensor cover to provide clearance for the re-oriented retention 
bolt.
    Since the original issue of this [Canadian] AD [which 
corresponds to AD 2010-13-04, Amendment 39-16335 (75 FR 35622, June 
23, 2010)], there have been several reports of pivot pin retention 
bolts found missing or damaged. Additional investigation determined 
that the failures were caused by high contact stresses on the 
retention bolt due to excessive frictional torque on the pivot pin 
and an adverse tolerance condition at the retention bolt.
    Revision 1 of this [Canadian] AD mandates the installation of a 
new pivot pin retention mechanism.

    This proposed AD would also add airplanes to the applicability. AD 
2010-13-04, Amendment 39-16335 (75 FR 35622, June 23, 2010), affected 
Model DHC-8-400 series airplanes, serial numbers 4001, 4003, 4004, 
4006, and 4008 through 4238 inclusive. This proposed AD would affect 
serial numbers 4001 through 4435 inclusive. You may examine the MCAI in 
the AD docket on the Internet at http://www.regulations.gov by 
searching for and locating it in Docket No. FAA-2013-1029.

Relevant Service Information

    Bombardier, Inc. has issued Service Bulletin 84-32-110, Revision A, 
dated April 8, 2013. The actions described in this service information 
are intended to correct the unsafe condition identified in the MCAI.

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.

Costs of Compliance

    We estimate that this proposed AD affects 383 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

[[Page 77617]]



                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Modification of the NLG trailing arm    3 work-hours x $85 per              $100            $355         $22,365
 [retained actions from AD               hour = $255.
 2010[dash]13[dash]04, Amendment
 39[dash]16335 (75 FR 35622, June 23,
 2010)].
Installation of new pivot pin           2 work-hours x $85 per              None             170          65,110
 retention mechanism [new proposed       hour = $170.
 action].
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this proposed 
AD may be covered under warranty, thereby reducing the cost impact on 
affected individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate

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 proposed 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 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket.

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) 
2010-13-04, Amendment 39-16335 (75 FR 35622, June 23, 2010), and adding 
the following new AD:

Bombardier, Inc.: Docket No. FAA-2013-1029; Directorate Identifier 
2013-NM-177-AD.

(a) Comments Due Date

    We must receive comments by February 7, 2014.

(b) Affected ADs

    This AD supersedes AD 2010-13-04, Amendment 39-16335 (75 FR 
35622, June 23, 2010).

(c) Applicability

    This AD applies to Bombardier, Inc. Model DHC-8-400, -401, and -
402 airplanes, certificated in any category, serial numbers 4001 
through 4435 inclusive.

(d) Subject

    Air Transport Association (ATA) of America Code 32, Landing 
Gear.

(e) Reason

    This AD was prompted by a report of several missing or damaged 
pivot pin retention bolts. We are issuing this AD to prevent failure 
of the pivot pin retention bolt, which could result in a loss of 
directional control or a NLG tire during take-off or landing.

(f) Compliance

    You are responsible for having the actions required by this AD 
performed within the compliance times specified, unless the actions 
have already been done.

(g) Retained Actions and Compliance

    This paragraph restates the requirements of paragraph (f)(1) of 
AD 2010-13-04, Amendment 39-16335 (75 FR 35622, June 23, 2010), with 
no changes. For airplanes having serial numbers 4001, 4003, 4004, 
4006, and 4008 through 4238 inclusive: Within 2,000 flight hours 
after July 28, 2010 (the effective date of AD 2010-13-04), modify 
the NLG trailing arm by incorporating Bombardier Modification 
Summary 4-113599, in accordance with the Accomplishment Instructions 
of Bombardier Service Bulletin 84-32-65, Revision A, dated March 2, 
2009.

(h) New Requirement of This AD: Installing a New Pivot Pin Retention 
Mechanism

    For airplanes having serial numbers 4001 through 4435 inclusive: 
Within 6,000 flight hours or 36 months after the effective date of 
this AD, whichever occurs first, install a new pivot pin retention 
mechanism by incorporating Bombardier Modification Summary 4-113749, 
in accordance with the Accomplishment Instructions of Bombardier 
Service Bulletin 84-32-110, Revision A, dated April 8, 2013.

(i) Credit for Actions Accomplished in Accordance With Previous Service 
Information

    (1) This paragraph provides credit for actions required by 
paragraph (g) of this AD, if those actions were performed before 
July 28, 2010 (the effective date of AD 2010-13-04, Amendment 39-
16335 (75 FR 35622, June 23, 2010)), using the Accomplishment 
Instructions of Bombardier Service Bulletin 84-32-65, dated December 
17, 2008, which is not incorporated by reference in this AD.
    (2) This paragraph provides credit for actions required by 
paragraph (h) of this AD, if those actions were performed before the 
effective date of this AD using Bombardier Service Bulletin 84-32-
110, dated December 21, 2012, which is not incorporated by reference 
in this AD.

(j) Other FAA AD Provisions

    The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, ANE-
170, New York Aircraft Certification Office (ACO), FAA, has

[[Page 77618]]

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 ACO, send it to ATTN: Program Manager, Continuing 
Operational Safety, FAA, New York ACO, 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. The AMOC approval letter must specifically reference this 
AD.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer, use these actions if they 
are FAA-approved. Corrective actions are considered FAA-approved if 
they were approved by the State of Design Authority (or its 
delegated agent, or by the DAH with a State of Design Authority's 
design organization approval). For a repair method to be approved, 
the repair approval must specifically refer to this AD. You are 
required to ensure the product is airworthy before it is returned to 
service.

(k) Related Information

    (1) Refer to Mandatory Continuing Airworthiness Information 
(MCAI) Canadian Airworthiness Directive CF-2009-29R1, dated August 
14, 2013, 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 it in Docket No. FAA-2013-1029.
    (2) 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 review copies of this 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.

    Issued in Renton, Washington, on December 11, 2013.
John P. Piccola,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-30468 Filed 12-23-13; 8:45 am]
BILLING CODE 4910-13-P


