AD 2011-13-08
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
Excessive wear of the shaft (tailstock) swaged bearing liners in elevator power control units (PCUs) due to paint contamination between the bearing roller and bearing liner, which could seize the bearing and lead to loss of controllability.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Perform a free-play check for shaft swaged bearings in elevator PCUs. Replace the elevator PCU with a serviceable one if excessive free-play is found, before further flight.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 2,000 flight hours after the effective date for airplanes with 8,000 or more total flight hours, or within 6,000 flight hours or before 10,000 total flight hours, whichever occurs first, for airplanes with less than 8,000 total flight hours.
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 with serial numbers 4001 through 4304 inclusive, certificated in any category.
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
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[Federal Register Volume 76, Number 123 (Monday, June 27, 2011)]
[Rules and Regulations]
[Pages 37253-37255]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-15367]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-0260; Directorate Identifier 2010-NM-242-AD;
Amendment 39-16731; AD 2011-13-08]
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.
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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:
Several reports have been received on the elevator power control
units (PCUs) where the shaft (tailstock) swaged bearing liners had
shown a higher than normal rate of wear. Investigation revealed that
the excessive wear was due to the paint contamination between the
bearing roller and bearing liner. The bearing paint contamination is
known to be abrasive and could seize the bearing.
This condition, if not corrected, could lead to excessive
airframe vibrations and difficulties in aircraft pitch control.
* * * * *
The unsafe condition is loss of controllability. We are issuing this AD
to require actions to correct the unsafe condition on these products.
DATES: This AD becomes effective August 1, 2011.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of August 1,
2011.
ADDRESSES: 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 U.S. Department of
Transportation, Docket Operations, M-30, West Building Ground Floor,
Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC.
FOR FURTHER INFORMATION CONTACT: Cesar Gomez, Aerospace Engineer,
Airframe and Mechanical Systems Branch, ANE-171, FAA, New York Aircraft
Certification Office (ACO), 1600 Stewart Avenue, Suite 410, Westbury,
New York 11590; telephone (516) 228-7318; fax (516) 794-5531.
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
That NPRM was published in the Federal Register on March 29, 2011 (76
FR 17362). That NPRM proposed to correct an unsafe condition for the
specified products. The MCAI states:
Several reports have been received on the elevator power control
units (PCUs) where the shaft (tailstock) swaged bearing liners had
shown a higher than normal rate of wear. Investigation revealed that
the excessive wear was due to the paint contamination between the
bearing roller and bearing liner. The bearing paint contamination is
known to be abrasive and could seize the bearing.
This condition, if not corrected, could lead to excessive
airframe vibrations and difficulties in aircraft pitch control.
This directive mandates a free-play check of the shaft swaged
bearing installed in the elevator PCU tailstock end and replacement
of the shaft swaged bearings if excessive free-play is found.
The unsafe condition is loss of controllability. You may obtain further
information by examining the MCAI in the AD docket.
Comments
We gave the public the opportunity to participate in developing
this AD. We received no comments on the NPRM or on the determination of
the cost to the public.
Conclusion
We reviewed the available data and determined that air safety and
the public interest require adopting the AD as proposed.
Differences Between This AD and the MCAI or Service Information
We have reviewed the MCAI and related service information and, in
[[Page 37254]]
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 our FAA policies. Any such differences
are highlighted in a NOTE within the AD.
Costs of Compliance
We estimate that this AD will affect 66 products of U.S. registry.
We also estimate that it will take about 2 work-hours per product to
comply with the basic requirements of this AD. The average labor rate
is $85 per work-hour. Based on these figures, we estimate the cost of
this AD to the U.S. operators to be $11,220, or $170 per product.
In addition, we estimate that any necessary follow-on actions would
take about 3 work-hours and require parts costing $33, for a cost of
$288 per product. We have no way of determining the number of products
that may need these actions.
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.
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 the NPRM, 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.
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:
2011-13-08 Bombardier, Inc.: Amendment 39-16731. Docket No. FAA-
2011-0260; Directorate Identifier 2010-NM-242-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective August
1, 2011.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Bombardier, Inc. Model DHC-8-400, -401,
and -402 airplanes having serial numbers (S/Ns) 4001 through 4304
inclusive; certificated in any category.
Subject
(d) Air Transport Association (ATA) of America Code 27: Flight
controls.
Reason
(e) The mandatory continuing airworthiness information (MCAI)
states:
Several reports have been received on the elevator power control
units (PCUs) where the shaft (tailstock) swaged bearing liners had
shown a higher than normal rate of wear. Investigation revealed that
the excessive wear was due to the paint contamination between the
bearing roller and bearing liner. The bearing paint contamination is
known to be abrasive and could seize the bearing.
This condition, if not corrected, could lead to excessive
airframe vibrations and difficulties in aircraft pitch control.
* * * * *
The unsafe condition is loss of controllability.
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.
Free-Play Check and Corrective Actions
(g) At the applicable time specified in paragraph (g)(1) or
(g)(2) of this AD: Perform a free-play check for any shaft swaged
bearing having part number (P/N) MS14103-7 that is installed in the
tailstock end of each elevator PCU (three PCUs per elevator
surface), having P/Ns 390600-1007 and 390600-1009, in accordance
with paragraph 3.B., Part A, of Bombardier Service Bulletin 84-27-
52, dated May 25, 2010.
(1) For airplanes that have accumulated 8,000 or more total
flight hours as of the effective date of this AD: Within 2,000
flight hours after the effective date of this AD.
(2) For airplanes that have accumulated less than 8,000 total
flight hours as of the effective date of this AD: Within 6,000
flight hours after the effective date of this AD or before the
accumulation of 10,000 total flight hours, whichever occurs first.
(h) If, during the check required by paragraph (g) of this AD,
the bearing free-play is within the limits specified in Bombardier
Service Bulletin 84-27-52, dated May 25, 2010, no further action is
required by this AD.
(i) If, during the check required by paragraph (g) of this AD,
the bearing free-play exceeds the limits specified in Bombardier
Service Bulletin 84-27-52, dated May 25, 2010: Before further
flight, replace the elevator PCU with a serviceable one, in
accordance with paragraph 3.B., Part B, of Bombardier Service
Bulletin 84-27-52, dated May 25, 2010.
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, New
York ACO,
[[Page 37255]]
ANE-170, 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-2010-28,
dated August 20, 2010; and Bombardier Service Bulletin 84-27-52,
dated May 25, 2010; for related information.
Material Incorporated by Reference
(l) You must use Bombardier Service Bulletin 84-27-52, dated May
25, 2010, to do the actions required by this AD, unless the AD
specifies otherwise.
(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#295d414d07585a4c5b404c5a69484c5b46074b46444b485b4d404c5b074a4644"><span class="__cf_email__" data-cfemail="1f6b777b316e6c7a6d767a6c5f7e7a6d70317d70727d7e6d7b767a6d317c7072">[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 June 14, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2011-15367 Filed 6-24-11; 8:45 am]
BILLING CODE 4910-13-P
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