Document ID: FAA-2011-0471-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Bombardier, Inc. Model DHC-8-400 Series Airplanes
Posted Date: 2011-05-12T04:00Z

[Federal Register Volume 76, Number 92 (Thursday, May 12, 2011)]
[Proposed Rules]
[Pages 27617-27619]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-11605]

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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]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc. Model DHC-8-400 Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
products listed above. This proposed 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.

The proposed AD would require actions that are intended to address the 
unsafe condition described in the MCAI.

DATES: We must receive comments on this proposed AD by June 27, 2011.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     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.
     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.
    For service information identified in this proposed 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. You may review copies of the referenced 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.

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 this proposed 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: Cathy Nguyen-Quoc, 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) 228-7323; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2011-0471; 
Directorate Identifier 2010-NM-219-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD based on those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued Canadian Airworthiness Directive CF-
2010-27, dated August 20, 2010 (referred to after this as ``the 
MCAI''), 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 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.

Relevant Service Information

    Bombardier Inc., has issued Service Bulletin 84-27-50, Revision C, 
dated July 26, 2010. The actions described in this service information 
are intended to

[[Page 27618]]

correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This Proposed 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 proposing this AD because we 
evaluated all pertinent information and determined an unsafe condition 
exists and is likely to exist or develop on other products of the same 
type design.

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 proposed 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 proposed AD.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 66 products of U.S. registry. We estimate the 
following costs to comply with this proposed AD:

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

    We estimate the following costs to do any necessary replacements 
that would be required based on the results of the proposed 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 proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 proposed 
regulation:
    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 proposed 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.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    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]

    2. The FAA amends Sec.  39.13 by adding the following new AD:

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

Comments Due Date

    (a) We must receive comments by June 27, 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

[[Page 27619]]

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 C, dated July 26, 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 C, 
dated July 26, 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 C, dated July 26, 
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 C, 
dated July 26, 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 C, dated July 26, 
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 84-27-50  Original............................  March 3, 2010.
Bombardier Service Bulletin 84-27-50  A...................................  April 28, 2010.
Bombardier Service Bulletin 84-27-50  B...................................  May 19, 2010.
----------------------------------------------------------------------------------------------------------------

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 C, dated July 26, 2010; for related information.

    Issued in Renton, Washington, on May 5, 2011.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-11605 Filed 5-11-11; 8:45 am]
BILLING CODE 4910-13-P