[Federal Register Volume 76, Number 175 (Friday, September 9, 2011)]
[Rules and Regulations]
[Pages 55785-55788]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-22277]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0471; Directorate Identifier 2010-NM-219-AD; 
Amendment 39-16800; AD 2011-18-18]
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 operators have reported pitch oscillations and/or 
elevator asymmetry caution lights illumination when flying with the 
autopilot engaged. Investigations revealed that loose rivets in the 
torque tube assemblies caused relative motion between the crank arms 
and torque tubes.
    Loose rivets could result in excessive wear and subsequent 
significant backlash in the driving crank arms. This condition, if 
left uncorrected, will progressively get worse and degrade the 
controllability of the aeroplane.

We are issuing this AD to require actions to correct the unsafe 
condition on these products.

DATES: This AD becomes effective October 14, 2011.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of October 14, 
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: Stephen Kowalski, 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) 228-7327; 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 May 12, 2011 (76 FR 
27617). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    Several operators have reported pitch oscillations and/or 
elevator asymmetry caution lights illumination when flying with the 
autopilot engaged. Investigations revealed that loose rivets in the 
torque tube assemblies caused relative motion between the crank arms 
and torque tubes.
    Loose rivets could result in excessive wear and subsequent 
significant backlash in the driving crank arms. This condition, if 
left

[[Page 55786]]

uncorrected, will progressively get worse and degrade the 
controllability of the aeroplane.

Required actions include doing an inspection for the part number of the 
left and right elevator torque tube assemblies and, if necessary, 
replacing the elevator torque tube assembly or replacing the elevator 
torque tube rivets, and re-identifying the assemblies. 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 (76 FR 27617, May 12, 
2011) or on the determination of the cost to the public.

Revised Service Information

    Bombardier Service Bulletin 84-27-50, Revision `D,' dated September 
22, 2010, has been issued for clarification, but adds no new actions. 
We have updated the references in paragraphs (g), (h), (i), and (m) of 
this AD to include Bombardier Service Bulletin 84-27-50, Revision `D,' 
dated September 22, 2010. We have also updated Table 1 of this AD to 
allow credit for Bombardier Service Bulletin 84-27-50, Revision `C,' 
dated July 26, 2010.

Conclusion

    We reviewed the relevant data, and determined that air safety and 
the public interest require adopting the AD with the changes described 
previously. We also determined that these changes will not increase the 
economic burden on any operator or increase the scope of the AD.

Differences Between This 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 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 the following costs to comply with this AD.

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
             Action                     Labor cost              Parts cost            product        operators
----------------------------------------------------------------------------------------------------------------
Inspection.....................  2 x $85 per hour = $170  None..................            $170         $11,220
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary replacements 
that would be required based on the results of the required inspection. 
We have no way of determining the number of aircraft that might need 
these replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace left torque tube......................  15 work-hours x $85 per hour =            $4,354          $5,629
                                                 $1,275.
Replace right torque tube.....................  15 work-hours x $85 per hour =             5,913           7,188
                                                 $1,275.
----------------------------------------------------------------------------------------------------------------

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:

[[Page 55787]]

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:

2011-18-18 Bombardier, Inc.: Amendment 39-16800. Docket No. FAA-
2011-0471; Directorate Identifier 2010-NM-219-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective October 
14, 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 through 4305 inclusive.

Subject

    (d) Air Transport Association (ATA) of America Code 27: Flight 
controls.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:
    Several operators have reported pitch oscillations and/or 
elevator asymmetry caution lights illumination when flying with the 
autopilot engaged. Investigations revealed that loose rivets in the 
torque tube assemblies caused relative motion between the crank arms 
and torque tubes.
    Loose rivets could result in excessive wear and subsequent 
significant backlash in the driving crank arms. This condition, if 
left uncorrected, will progressively get worse and degrade the 
controllability of the aeroplane.

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.

Inspection for Part Number

    (g) At the applicable times identified in paragraphs (g)(1) and 
(g)(2) of this AD, do an inspection to determine the part numbers of 
the left and right elevator torque tubes, in accordance with the 
Accomplishment Instructions of Bombardier Service Bulletin 84-27-50, 
Revision `D,' dated September 22, 2010. A review of airplane 
maintenance records is acceptable in lieu of this inspection if the 
part numbers of the left and right elevator torque tubes can be 
conclusively determined from that review.
    (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, but before the 
accumulation of 10,000 total flight hours.

Corrective Actions

    (h) If, as a result of the inspection required by paragraph (g) 
of this AD, any left elevator torque tube has part number (P/N) 
82760709-009, at the applicable time in paragraph (g)(1) or (g)(2) 
of this AD, do the actions in paragraph (h)(1) or (h)(2) of this AD.
    (1) Replace the elevator torque tube with a new elevator torque 
tube having P/N 82760709-011, in accordance with the Accomplishment 
Instructions of Bombardier Service Bulletin 84-27-50, Revision `D,' 
dated September 22, 2010.
    (2) Replace the rivets in each elevator torque tube assembly 
with Hi Lite pins having P/N B0206001AG8 and collars having P/N 
HST1070CY, and re-identify the elevator torque tube assembly having 
P/N 82760709-009, in accordance with the Accomplishment Instructions 
of Bombardier Service Bulletin 84-27-50, Revision `D,' dated 
September 22, 2010.
    (i) If, as a result of the inspection required by paragraph (g) 
of this AD, any right elevator torque tube has P/N 82760757-009, at 
the applicable time in paragraph (g)(1) or (g)(2) of this AD, do the 
actions in paragraph (i)(1) or (i)(2) of this AD.
    (1) Replace the elevator torque tube with a new elevator torque 
tube having P/N 82760757-011, in accordance with the Accomplishment 
Instructions of Bombardier Service Bulletin 84-27-50, Revision `D,' 
dated September 22, 2010.
    (2) Replace the rivets in each elevator torque tube assembly 
with Hi Lite pins having P/N B0206001AG8 and collars having P/N 
HST1070CY, and re-identify the elevator torque tube assembly having 
P/N 82760757-009, in accordance with the Accomplishment Instructions 
of Bombardier Service Bulletin 84-27-50, Revision `D,' dated 
September 22, 2010.

Credit for Actions Accomplished in Accordance With Previous Service 
Information

    (j) Actions done before the effective date of this AD, in 
accordance with the service bulletins listed in table 1 of this AD, 
are considered acceptable for compliance with the corresponding 
action specified in this AD.

                    Table 1--Credit Service Bulletins
------------------------------------------------------------------------
       Service Bulletin              Revision               Date
------------------------------------------------------------------------
Bombardier Service Bulletin 84- Original.........  March 3, 2010.
 27-50.
Bombardier Service Bulletin 84- A................  April 28, 2010.
 27-50.
Bombardier Service Bulletin 84- B................  May 19, 2010.
 27-50.
Bombardier Service Bulletin 84- C................  July 26, 2010.
 27-50.
------------------------------------------------------------------------

Parts Installation

    (k) As of the effective date of this AD, no person may install 
on any airplane an elevator torque tube assembly having P/N 
82760709-009 or 82760757-009.

FAA AD Differences

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

Other FAA AD Provisions

    (l) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New 
York Aircraft Certification Office (ACO), 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

    (m) Refer to MCAI Canadian Airworthiness Directive CF-2010-27, 
dated August 20, 2010; and Bombardier Service Bulletin 84-27-50, 
Revision `D,' dated September 22, 2010; for related information.

Material Incorporated by Reference

    (n) You must use Bombardier Service Bulletin 84-27-50, Revision 
`D,' dated September 22, 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.

[[Page 55788]]

    (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 [email protected]; 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 August 23, 2011.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-22277 Filed 9-8-11; 8:45 am]
BILLING CODE 4910-13-P