Document ID: FAA-2011-0260-0005
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Bombardier, Inc. Model DHC-8-400 Series Airplanes
Posted Date: 2011-06-27T04:00Z

[Federal Register Volume 76, Number 123 (Monday, June 27, 2011)]
[Rules and Regulations]
[Pages 37253-37255]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-15367]

-----------------------------------------------------------------------

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.

-----------------------------------------------------------------------

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 http://www.regulations.gov 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 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 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 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 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