
[Federal Register Volume 76, Number 47 (Thursday, March 10, 2011)]
[Rules and Regulations]
[Pages 13080-13082]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-5085]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0154; Directorate Identifier 2011-NM-016-AD; 
Amendment 39-16624; AD 2011-05-14]
RIN 2120-AA64


Airworthiness Directives; Bombardier, Inc. Model DHC-8-400 Series 
Airplanes

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

ACTION: Final rule; request for comments.

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SUMMARY: We are adopting a new airworthiness directive (AD) for the 
products listed above. This AD results from mandatory continuing 
airworthiness information (MCAI) originated by an aviation authority of 
another country to identify and correct an unsafe condition on an 
aviation product. The MCAI describes the unsafe condition as:

    Two cases of the main landing gear (MLG) alternate extension 
system (AES) cam mechanism failure were found during line checks. 
The cam mechanism operates the cable to open the MLG door and 
releases the MLG uplock in sequence. In the case where it is 
necessary to deploy the MLG using the AES, the failure of the MLG 
AES cam mechanism on one side will lead to an unsafe asymmetrical 
landing configuration.
* * * * *
The unsafe condition is possible loss of control during landing. This 
AD requires actions that are intended to address the unsafe condition 
described in the MCAI.

DATES: This AD becomes effective March 25, 2011.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of March 25, 
2011.
    We must receive comments on this AD by April 25, 2011.

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 W12-40, 1200 New 
Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.

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 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. Comments will be available in the AD docket shortly 
after receipt.

FOR FURTHER INFORMATION CONTACT: Fabio Buttitta, 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) 228-7303; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Discussion

    The Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued Canadian Emergency Airworthiness 
Directive CF-2011-01, dated January 17, 2011 (referred to after this as 
``the MCAI''), to correct an unsafe condition for the specified 
products. The MCAI states:

    Two cases of the main landing gear (MLG) alternate extension 
system (AES) cam mechanism failure were found during line checks. 
The cam mechanism operates the cable to open the MLG door and 
releases the MLG uplock in sequence. In the case where it is 
necessary to deploy the MLG using the AES, the failure of the MLG 
AES cam mechanism on one side will lead to an unsafe asymmetrical 
landing configuration.
    Preliminary investigation indicates that the cam mechanism 
failure may have occurred and remained dormant after a previous AES 
operation. The cam mechanism may not have fully returned to the 
normal rested position. With the cam mechanism out of normal rested 
position, normal powered landing gear door operation could introduce 
sufficient loads to fracture the cam mechanism or rupture the door 
release cable.
    This directive mandates the initial and subsequent [detailed] 
inspections for proper operation of the MLG AES cam mechanism, and 
rectify [repair or replace cam assembly with new or serviceable cam 
assembly] as necessary.

The unsafe condition is possible loss of control during landing. You 
may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

    Bombardier has issued Repair Drawing 8/4-32-0160, Issue 2, dated 
January 18, 2011. 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 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 issuing this AD because we 
evaluated all pertinent information and determined the unsafe condition 
exists and is likely to exist or develop on other products of the same 
type design.

Differences Between the AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might also have required different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
highlighted in a Note within the AD.

FAA's Determination of the Effective Date

    An unsafe condition exists that requires the immediate adoption of 
this

[[Page 13081]]

AD. The FAA has found that the risk to the flying public justifies 
waiving notice and comment prior to adoption of this rule because two 
cases of the main landing gear (MLG) alternate extension system (AES) 
cam mechanism failure were found during line checks. The cam mechanism 
operates the cable to open the MLG door and releases the MLG uplock in 
sequence. In the case where it is necessary to deploy the MLG using the 
AES, the failure of the MLG AES cam mechanism on one side will lead to 
an unsafe asymmetrical landing configuration. Therefore, we determined 
that notice and opportunity for public comment before issuing this AD 
are impracticable and that good cause exists for making this amendment 
effective in fewer than 30 days.

Comments Invited

    This AD is a final rule that involves requirements affecting flight 
safety, and we did not precede it by notice and opportunity for public 
comment. We invite you to send any written relevant data, views, or 
arguments about this AD. Send your comments to an address listed under 
the ADDRESSES section. Include ``Docket No. FAA-2011-0154; Directorate 
Identifier 2011-NM-016-AD'' at the beginning of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this AD. We will consider all 
comments received by the closing date and may amend this AD 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 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 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); and
    3. 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 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.

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 AD:

2011-05-14 Bombardier, Inc.: Amendment 39-16624. Docket No. FAA-
2011-0154; Directorate Identifier 2011-NM-016-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective March 
25, 2011.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Bombardier, Inc. Model DHC-8-400, -401, 
and -402 airplanes, certificated in any category, serial numbers 
4001 and subsequent.

Subject

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

Reason

    (e) The mandatory continued airworthiness information (MCAI) 
states:
    Two cases of the main landing gear (MLG) alternate extension 
system (AES) cam mechanism failure were found during line checks. 
The cam mechanism operates the cable to open the MLG door and 
releases the MLG uplock in sequence. In the case where it is 
necessary to deploy the MLG using the AES, the failure of the MLG 
AES cam mechanism on one side will lead to an unsafe asymmetrical 
landing configuration.
* * * * *
    The unsafe condition is possible loss of control during landing.

Compliance

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

Actions

    (g) Within 50 flight hours or 10 days after the effective date 
of this AD, whichever occurs first, do a detailed inspection for 
proper operation of the MLG AES cam mechanism, in accordance with 
paragraph A) of Bombardier Repair Drawing 8/4-32-0160, Issue 2, 
dated January 18, 2011. Repeat the inspection thereafter at 
intervals not to exceed 50 flight hours or 10 days, whichever occurs 
first.
    (1) If the cam mechanism is found to reset to the normal rested 
position without any sticking or binding, it is operating properly.
    (2) If the cam mechanism has not reset to its normal rested 
position, or if any sticking or binding is observed, before further 
flight, remove the cam assembly, in accordance with paragraph A) of 
Bombardier Repair Drawing 8/4-32-0160, Issue 2, dated January 18, 
2011, and do the actions in paragraph (g)(2)(i) or (g)(2)(ii) of 
this AD.
    (i) Repair the cam mechanism assembly, including doing detailed 
inspections for discrepancies (including an inspection to determine 
proper operation, an inspection for damage, an inspection for 
corrosion and cadmium coating degradation, and inspections to 
determine dimensions are within the limits specified in paragraph B) 
of Bombardier Repair Drawing 8/4-32-0160, Issue 2, dated January 18, 
2011), in accordance with paragraph B) of Bombardier Repair Drawing 
8/4-32-0160, Issue 2, dated January 18, 2011, and install the 
repaired cam assembly in accordance with paragraph C) of Bombardier 
Repair Drawing 8/4-32-0160, Issue 2, dated January 18, 2011.
    (ii) Install a new or serviceable cam assembly, in accordance 
with paragraph C) of Bombardier Repair Drawing 8/4-32-0160, Issue 2, 
dated January 18, 2011.
    (3) If the cam mechanism is found damaged or inoperative during 
the repair specified in paragraph (g)(2)(i) of this AD, or if any 
discrepancies are found and Bombardier Repair Drawing 8/4-32-0160, 
Issue 2, dated January 18, 2011, does not specify repairs for those 
discrepancies, or repairs specified in paragraph (g)(2)(i) of this 
AD cannot be accomplished: Before further flight, repair and 
reinstall using a method approved by the Manager, ANE-170, New

[[Page 13082]]

York Aircraft Certification Office (ACO), FAA, or Transport Canada 
Civil Aviation (TCCA) (or its delegated agent), or install new or 
serviceable cam assembly in accordance with paragraph C) of 
Bombardier Repair Drawing 8/4-32-0160, Issue 2, dated January 18, 
2011.

Credit for Actions Accomplished in Accordance With Previous Service 
Information

    (h) Actions done before the effective date of this AD in 
accordance with Bombardier 8/4-32-0160, Issue 1, dated January 14, 
2011, are acceptable for compliance with the corresponding 
requirements of this AD.

FAA AD Differences

    Note 1:  This AD differs from the MCAI and/or service 
information as follows: No difference.

Other FAA AD Provisions

    (i) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, ANE-
170, New York ACO, 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 ACO, send it 
to Attn: Program Manager, Continuing Operational Safety, FAA, New 
York ACO, 1600 Stewart Avenue, Suite 410, Westbury, New York 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 or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.

Related Information

    (j) Refer to MCAI Canadian Emergency Airworthiness Directive CF-
2011-01, dated January 17, 2011; and Bombardier Repair Drawing 8/4-
32-0160, Issue 2, dated January 18, 2011; for related information.

Material Incorporated by Reference

    (k) You must use Bombardier Repair Drawing 8/4-32-0160, Issue 2, 
dated January 18, 2011, to do the actions required by this AD, 
unless the AD specifies otherwise. Bombardier Repair Drawing 8/4-32-
0160, Issue 2, dated January 18, 2011, contains the following 
effective pages:

----------------------------------------------------------------------------------------------------------------
                                                 Issue level shown
           Sheet number shown on page                 on page                    Date shown on page
----------------------------------------------------------------------------------------------------------------
1..............................................                  2  January 18, 2011
2, 3, 11.......................................                  2  None shown *
4-10...........................................                  1  None shown *
----------------------------------------------------------------------------------------------------------------
(* The issue date of this document is found only on the first page of the document; no other page of this
  document contains this information.)

    (1) The Director of the Federal Register approved the 
incorporation by reference of this service information under 5 
U.S.C. 552(a) and 1 CFR part 51.
    (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; e-mail thd.qseries@aero.bombardier.com; Internet 
http://www.bombardier.com.
    (3) You may review copies of the service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington. For information on the availability of this material at 
the FAA, call 425-227-1221.
    (4) You may also review copies of the 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/code_of_federal_regulations/ibr_locations.html.

    Issued in Renton, Washington, on February 22, 2011.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-5085 Filed 3-9-11; 8:45 am]
BILLING CODE 4910-13-P


