AD 2011-05-14
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bombardier | Various | Airworthiness Directives; Bombardier, Inc. Model DHC-8-400 Series Airplanes |
| aircraft | Aviat | Various | Airworthiness Directives; Bombardier, Inc. Model DHC-8-400 Series Airplanes |
Unsafe Condition
Failure of the main landing gear (MLG) alternate extension system (AES) cam mechanism on one side can lead to an unsafe asymmetrical landing configuration, potentially resulting in possible loss of control during landing.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect the MLG AES cam mechanism for proper operation. Rectify (repair or replace) the cam assembly as necessary.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the compliance times specified in the AD, unless the actions have already been performed.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Bombardier, Inc. Model DHC-8-400, -401, and -402 airplanes, certificated in any category, serial numbers 4001 and subsequent.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
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:
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 76, Number 47 (Thursday, March 10, 2011)]
[Rules and Regulations]
[Pages 13080-13082]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[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.
-----------------------------------------------------------------------
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:
<bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
<bullet> Fax: (202) 493-2251.
<bullet> 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.
<bullet> 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 <a href="http://www.regulations.gov">http://www.regulations.gov</a>; 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 <a href="http://www.regulations.gov">http://www.regulations.gov</a>, 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 <a href="/cdn-cgi/l/email-protection#cfbba7abe1bebcaabda6aabc8faeaabda0e1ada0a2adaebdaba6aabde1aca0a2"><span class="__cf_email__" data-cfemail="6c180408421d1f091e05091f2c0d091e03420e03010e0d1e0805091e420f0301">[email protected]</span></a>; Internet
<a href="http://www.bombardier.com">http://www.bombardier.com</a>.
(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: <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
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
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