AD 2011-15-09
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 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 using the revised inspection procedure. 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 100 flight hours after the effective date of the AD.
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Bombardier, Inc. Model DHC-8-400 Series airplanes with the main landing gear alternate extension system (AES) cam mechanism installed.
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 that would supersede an existing AD. 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 137 (Monday, July 18, 2011)]
[Rules and Regulations]
[Pages 42033-42036]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-17813]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-0718; Directorate Identifier 2011-NM-117-AD;
Amendment 39-16756; AD 2011-15-09]
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 that would
[[Page 42034]]
supersede an existing AD. 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 August 2, 2011.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in the AD as of August 2,
2011.
The Director of the Federal Register approved the incorporation by
reference of a certain other publication listed in the AD as of March
25, 2011 (76 FR 13080, March 10, 2011).
We must receive comments on this AD by September 1, 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: Cesar Gomez, 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) 228-7318; fax (516) 794-5531.
SUPPLEMENTARY INFORMATION:
Discussion
On February 22, 2011, we issued AD 2011-05-14, Amendment 39-16624
(76 FR 13080, March 10, 2011). That AD required actions intended to
address an unsafe condition on the products listed above.
Since we issued AD 2011-05-14, we have received a report that the
service information referenced in that AD as a source of accomplishment
information was found to have inadequate inspection procedures.
Transport Canada Civil Aviation (TCCA), which is the aviation authority
for Canada, has issued Canadian Airworthiness Directive CF-2011-01R1,
dated May 20, 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.
Since the original issue of this [Canadian] directive,
Bombardier Inc. has determined that the existing inspection
procedure is insufficient for verification of proper MLG AES cam
mechanism operation, and has superseded this inspection procedure.
This revision of the [Canadian] directive mandates the use of the
latest inspection [and rectification] procedure.
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 3, dated
February 15, 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 AD. The FAA has found that the risk to the flying public justifies
waiving notice and comment prior to adoption of this rule because since
we issued AD 2011-05-14, Bombardier has determined that the existing
inspection procedure referenced in AD 2011-05-14 is insufficient for
verification of proper MLG AES cam mechanism operation, and has
provided a revised inspection procedure. 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. An asymmetrical landing configuration could result in
possible loss of control during landing. This AD mandates the use of
the revised inspection procedures. Therefore, we determined that notice
and opportunity
[[Page 42035]]
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-2011-0718; Directorate
Identifier 2011-NM-117-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 removing Amendment 39-16624 (76 FR
13080, March 10, 2011) and adding the following new AD:
2011-15-09 Bombardier, Inc.: Amendment 39-16756. Docket No. FAA-
2011-0718; Directorate Identifier 2011-NM-117-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective August
2, 2011.
Affected ADs
(b) This AD supersedes AD 2011-05-14, Amendment 39-16624.
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.
Restatement of Requirements of AD 2011-05-14, With New Service
Information
(g) Within 50 flight hours or 10 days after March 25, 2011 (the
effective date of AD 2011-05-14), 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; or Issue 3,
dated February 15, 2011. Repeat the inspection thereafter at
intervals not to exceed 50 flight hours or 10 days, whichever occurs
first, until the inspection required by paragraph (i) of this AD is
accomplished.
(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; or Issue 3, dated February 15, 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; or Issue 3, dated February 15, 2011), in accordance with
paragraph B) of Bombardier Repair Drawing 8/4-32-0160, Issue 2,
dated January 18, 2011; or Issue 3, dated February 15, 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; or Issue 3, dated February 15, 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; or Issue 3, dated February 15, 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; or Issue 3, dated February 15,
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 York Aircraft Certification Office
(ACO), FAA, or Transport Canada Civil Aviation (TCCA) (or its
delegated agent); or install a new or serviceable cam assembly, in
[[Page 42036]]
accordance with paragraph C) of Bombardier Repair Drawing 8/4-32-
0160, Issue 2, dated January 18, 2011; or Issue 3, dated February
15, 2011.
Credit for Actions Accomplished in Accordance With Previous Service
Information
(h) Actions done before March 25, 2011, 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.
New Requirements of This AD
(i) 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 3,
dated February 15, 2011. Repeat the inspection thereafter at
intervals not to exceed 50 flight hours or 10 days, whichever occurs
first. Accomplishing this inspection terminates the requirements of
paragraph (g) of this AD.
(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 3, dated February 15,
2011, and do the actions in paragraph (i)(2)(i) or (i)(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 3, dated February
15, 2011), in accordance with paragraph B) of Bombardier Repair
Drawing 8/4-32-0160, Issue 3, dated February 15, 2011; and install
the repaired cam assembly in accordance with paragraph C) of
Bombardier Repair Drawing 8/4-32-0160, Issue 3, dated February 15,
2011.
(ii) Install a new or serviceable cam assembly, in accordance
with paragraph C) of Bombardier Repair Drawing 8/4-32-0160, Issue 3,
dated February 15, 2011.
(3) If the cam mechanism is found damaged or inoperative during
the repair specified in paragraph (i)(2)(i) of this AD, or if any
discrepancies are found and Bombardier Repair Drawing 8/4-32-0160,
Issue 3, dated February 15, 2011, does not specify repairs for those
discrepancies, or repairs specified in paragraph (i)(2)(i) of this
AD cannot be accomplished: Before further flight, repair and
reinstall using a method approved by the Manager, ANE-170, New York
Aircraft Certification Office (ACO), FAA, or Transport Canada Civil
Aviation (TCCA) (or its delegated agent); or install a new or
serviceable cam assembly, in accordance with paragraph C) of
Bombardier Repair Drawing 8/4-32-0160, Issue 3, dated February 15,
2011.
FAA AD Differences
Note 1: This AD differs from the MCAI and/or service
information as follows: No differences.
Other FAA AD Provisions
(j) 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 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
(k) Refer to MCAI Canadian Airworthiness Directive CF-2011-01R1,
dated May 20, 2011; Bombardier Repair Drawing 8/4-32-0160, Issue 2,
dated January 18, 2011; and Bombardier Repair Drawing 8/4-32-0160,
Issue 3, dated February 15, 2011; for related information.
Material Incorporated by Reference
(l) You must use Bombardier Repair Drawing 8/4-32-0160, Issue 2,
dated January 18, 2011; or Bombardier Repair Drawing 8/4-32-0160,
Issue 3, dated February 15, 2011; as applicable; to do the actions
required by this AD, unless the AD specifies otherwise. The issue
dates for Bombardier Repair Drawing 8/4-32-0160, Issue 3, dated
February 15, 2011, are identified on only the first page of that
document.
(1) The Director of the Federal Register approved the
incorporation by reference of Bombardier Repair Drawing 8/4-32-0160,
Issue 3, dated February 15, 2011, under 5 U.S.C. 552(a) and 1 CFR
part 51.
(2) The Director of the Federal Register previously approved the
incorporation by reference of Bombardier Repair Drawing 8/4-32-0160,
Issue 2, dated January 18, 2011, on March 25, 2011 (76 FR 13080,
March 10, 2011).
(3) 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#64100c004a151701160d0117240501160b4a060b09060516000d01164a070b09"><span class="__cf_email__" data-cfemail="1f6b777b316e6c7a6d767a6c5f7e7a6d70317d70727d7e6d7b767a6d317c7072">[email protected]</span></a>; Internet
<a href="http://www.bombardier.com">http://www.bombardier.com</a>.
(4) 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.
(5) 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 July 6, 2011.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2011-17813 Filed 7-15-11; 8:45 am]
BILLING CODE 4910-13-P
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