[Federal Register Volume 70, Number 244 (Wednesday, December 21, 2005)]
[Rules and Regulations]
[Pages 75727-75729]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-24245]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-22403; Directorate Identifier 2005-NM-144-AD; 
Amendment 39-14426; AD 2005-26-05]
RIN 2120-AA64


Airworthiness Directives; Bombardier Model DHC-8-400 Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for 
certain Bombardier Model DHC-8-400 series airplanes. This AD requires 
an inspection of the laminated shims for cracks, damage, or extrusion 
between the forward attachment fittings of the horizontal stabilizer 
and the top rib of the vertical stabilizer; a torque check of the 
attachment bolts in the attachment fittings of the front, middle, and 
rear spars; and corrective actions if necessary. This AD results from a 
report indicating that delaminated shims extruded from the interface 
between the forward attaching fittings of the horizontal stabilizer and 
the top rib of the vertical stabilizer, and that inadequate torque 
values of some bolts were found. We are issuing this AD to prevent 
reduced structural integrity of the horizontal stabilizer, and 
consequent loss of controllability of the airplane.

DATES: This AD becomes effective January 25, 2006.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of January 25, 
2006.

ADDRESSES: You may examine the AD docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street SW., Nassif Building, 
Room PL-401, Washington, DC.
    Contact Bombardier, Inc., Bombardier Regional Aircraft Division, 
123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada, for service 
information identified in this AD.

FOR FURTHER INFORMATION CONTACT: George Duckett, Aerospace Engineer, 
Airframe and Propulsion Branch, ANE-171, FAA, New York Aircraft 
Certification Office, 1600 Stewart Avenue, Suite 410, Westbury, New 
York 11590; telephone (516) 228-7325; fax (516) 794-5531.

SUPPLEMENTARY INFORMATION:

Examining the Docket

    You may examine the airworthiness directive (AD) docket on the 
Internet at http://dms.dot.gov or in person at the Docket Management 
Facility office between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Management Facility office 
(telephone (800) 647-5227) is located on the plaza level of the Nassif 
Building at the street address stated in the ADDRESSES section.

Discussion

    The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 
CFR part 39 to include an AD that would apply to certain Bombardier 
Model DHC-8-400 series airplanes. That NPRM was published in the 
Federal Register on September 14, 2005 (70 FR 54316). (An NPRM 
correction was published in the Federal Register on September 30, 2005 
(70 FR 57221).) That NPRM proposed to require an inspection of the 
laminated shims for cracks, damage, or extrusion between the forward 
attachment fittings of the horizontal stabilizer and the top rib of the 
vertical stabilizer; a torque check of the attachment bolts in the 
attachment fittings of the front, middle, and rear spars; and 
corrective actions if necessary.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We have considered the comment received.

Request for Credit for Doing Bombardier All Operator Message (AOM)

    One commenter requests that operators be given credit for doing the 
procedures in accordance with

[[Page 75728]]

Bombardier AOM 096B, dated June 12, 2003, before the effective date of 
the AD, as an alternative method of compliance (AMOC) with the 
requirements of paragraphs (i)(1) and (i)(2) of the NPRM.
    We agree with the commenter that accomplishing the actions 
specified in Bombardier AOM 096B before the effective date of this AD 
is acceptable for compliance with the detailed inspection and torque 
check required by paragraphs (i)(1) and (i)(2) of the AD. We also have 
determined that those actions are also acceptable for the replacement 
requirements of the AD. We have revised paragraph (g) of the final rule 
accordingly and reidentified subsequent paragraphs.

Explanation of Change to Identified Repair Drawings

    We have revised paragraph (h) of the final rule to refer to the 
correct revisions and dates of Bombardier Repair Drawing RD 8/4-55-090 
and RD 8/4-55-094.

Clarification of AMOC Paragraph

    We have revised this action to clarify the appropriate procedure 
for notifying the principal inspector before using any approved AMOC on 
any airplane to which the AMOC applies.

Conclusion

    We have carefully reviewed the available data, including the 
comment received, and determined that air safety and the public 
interest require adopting the AD with the changes described previously. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Costs of Compliance

    The following table provides the estimated costs for U.S. operators 
to comply with this AD.

                                                                     Estimated Costs
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                                                                                                                                 Number of
                                                                Average                                              Cost per      U.S.-
                     Action                       Work hours   labor rate                   Parts                    airplane    registered   Fleet cost
                                                                per hour                                                         airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Detailed inspection and torque check...........            2          $65  None..................................         $130           19       $2,470
Replacement....................................           30          $65  Free of charge........................       $1,950           19       37,050
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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 have 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 that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866;
    (2) Is not a ``significant rule'' under 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. See the ADDRESSES 
section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

2005-26-05 Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 
39-14426. Docket No. FAA-2005-22403; Directorate Identifier 2005-NM-
144-AD.

Effective Date

    (a) This AD becomes effective January 25, 2006.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Bombardier Model DHC-8-400 series 
airplanes, certificated in any category; serial numbers 4001, and 
4003 through 4081 inclusive.

Unsafe Condition

    (d) This AD results from a report indicating that laminated 
shims were delaminated and extruded from the interface between the 
forward attaching fittings of horizontal stabilizer and the top rib 
of the vertical stabilizer, and that inadequate torque values of 
some bolts were found. We are issuing this AD to prevent reduced 
structural integrity of the horizontal stabilizer, and consequent 
loss of controllability of the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Service Information

    (f) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of Bombardier Service Bulletin 84-55-02, 
Revision ``A,'' dated January 12, 2005.
    (g) Accomplishing a detailed inspection, a breakaway torque 
check, and corrective actions if necessary before the effective date 
of this AD in accordance with Bombardier Service Bulletin 84-55-02, 
dated December 11, 2003; or Bombardier All Operator Message 096B, 
dated June 12, 2003; is acceptable for compliance with the 
corresponding requirements of this AD.

[[Page 75729]]

    (h) Accomplishing the repair before the effective date of this 
AD in accordance with the applicable Bombardier repair drawings in 
Table 1 of this AD is acceptable for compliance with the 
requirements of this AD.

                        Table 1.--Repair Drawings
------------------------------------------------------------------------
    Bombardier repair drawing       RD issue             Dated
------------------------------------------------------------------------
RD 8/4-55-083....................          3  April 16, 2003.
RD 8/4-55-084....................          1  May 5, 2003.
RD 8/4-55-089....................          2  June 6, 2003.
RD 8/4-55-090....................          8  October 9, 2003.
RD 8/4-55-093....................          2  June 20, 2003.
RD 8/4-55-094....................          4  October 20, 2003.
RD 8/4-55-106....................          2  July 31, 2003.
RD 8/4-55-110....................          3  October 1, 2003.
RD 8/4-55-138....................          1  October 29, 2003.
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Detailed Inspection and Torque Check

    (i) Within 4,000 flight hours after the effective date of this 
AD, do the actions specified in paragraphs (i)(1) and (i)(2) of this 
AD in accordance with Part A of the service bulletin.
    (1) Do a detailed inspection of the laminated shims for cracks, 
damage, or extrusion between the forward attachment fittings of the 
horizontal stabilizer and the top rib of the vertical stabilizer.

    Note 1: For the purposes of this AD, a detailed inspection is: 
``An intensive examination of a specific item, installation, or 
assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good 
lighting at an intensity deemed appropriate. Inspection aids such as 
mirror, magnifying lenses, etc., may be necessary. Surface cleaning 
and elaborate procedures may be required.''

    (2) Do a breakaway torque check of the six attachment bolts in 
the attachment fittings of the front, middle, and rear spars.

Corrective Actions

    (j) If, during the inspection required by paragraph (i)(1) of 
this AD, any cracked, damaged, or extruded laminated shim is found, 
before further flight, replace the discrepant laminated shim with a 
solid shim, and replace the attachment bolts, barrel nuts, and 
retainers of both front spars with new parts, in accordance with 
Parts A and B of the service bulletin.
    (k) If, during the torque check required by paragraph (i)(2) of 
this AD, any attachment bolt is found with a breakaway torque value 
outside the limits specified in the service bulletin, before further 
flight, replace the attachment bolt and its corresponding barrel nut 
and retainer with new parts, in accordance Part A of the service 
bulletin.

Replacement of Laminated Shims

    (1) Within 8,000 flight hours after the effective date of this 
AD, unless previously accomplished in accordance with paragraph (j) 
of this AD, replace the laminated shims, between the forward 
attachment fittings of the horizontal stabilizer and the top rib of 
the vertical stabilizer, with solid shims and replace the 
corresponding barrel nut and retainer with new parts, in accordance 
with Part B of the service bulletin.

No Reporting

    (m) Although the service bulletin referenced in this AD 
specifies to submit certain information to the manufacturer, this AD 
does not include that requirement.

Alternative Methods of Compliance (AMOCs)

    (n)(1) The Manager, New York Aircraft Certification Office, FAA, 
has the authority to approve AMOCs for this AD, if requested in 
accordance with the procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

Related Information

    (o) Canadian airworthiness directive CF-2005-07, issued March 
21, 2005, also addresses the subject of this AD.

Material Incorporated by Reference

    (p) You must use Bombardier Service Bulletin 84-55-02, Revision 
`A,' dated January 12, 2005, to perform the actions that are 
required by this AD, unless the AD specifies otherwise. The Director 
of the Federal Register approved the incorporation by reference of 
this document in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. 
Contact Bombardier, Inc., Bombardier Regional Aircraft Division, 123 
Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada, for a copy of 
this service information. You may review copies at the Docket 
Management Facility, U.S. Department of Transportation, 400 Seventh 
Street SW., room PL-401, Nassif Building, Washington, DC; on the 
Internet at http://dms.dot.gov; or at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at the 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 December 13, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-24245 Filed 12-20-05; 8:45 am]
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