[Federal Register Volume 72, Number 30 (Wednesday, February 14, 2007)]
[Rules and Regulations]
[Pages 6927-6928]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-2411]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2006-26241; Directorate Identifier 2006-NM-155-AD; 
Amendment 39-14938; AD 2007-04-07]
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 
inspecting to determine the manufacturer's date of certain V-band 
clamps on the engine exhaust shroud assembly, and doing related 
investigative/corrective actions if necessary. This AD results from a 
report of a discrepancy found during a maintenance inspection on a V-
band clamp located on the engine exhaust duct shroud. The clamp ends 
were touching (although the correct fastener torque had been applied), 
resulting in reduced clamp force on the flanges. We are issuing this AD 
to prevent vibration in the duct shroud and fretting of the V-band 
clamp and flanges, which could result in cracking of the flanges and 
consequent release of hot exhaust gases from the engine tailpipe and 
damage to adjacent structure. This situation could trigger the fire 
warning system and result in an in-flight emergency, such as the 
flightcrew shutting down the engine and activating the fire suppression 
system.

DATES: This AD becomes effective March 21, 2007.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in the AD as of March 21, 
2007.

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: Richard Fiesel, 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) 228-7304; 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 November 3, 2006 (71 FR 64651). That NPRM proposed 
to require inspecting to determine the manufacturer's date of certain 
V-band clamps on the engine exhaust shroud assembly, and doing related 
investigative/corrective actions if necessary.

Comments

    We provided the public the opportunity to participate in the 
development of this AD. We received no comments on the NPRM or on the 
determination of the cost to the public.

Conclusion

    We have carefully reviewed the available data and determined that 
air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

    This AD affects about 21 airplanes of U.S. registry. The required 
actions take about 3 work hours per airplane, at an average labor rate 
of $80 per work hour. Required parts cost is minimal. Based on these 
figures, the estimated cost of this AD for U.S. operators is $5,040, or 
$240 per airplane.

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.

[[Page 6928]]

    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):

2007-04-07 Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 
39-14938. FAA-2006-26241; Directorate Identifier 2006-NM-155-AD.

Effective Date

    (a) This AD becomes effective March 21, 2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Bombardier Model DHC-8-400 series 
airplanes, certificated in any category; as identified in Bombardier 
Service Bulletin 84-78-01, Revision `A,' dated September 15, 2005.

Unsafe Condition

    (d) This AD results from a report of a discrepancy found during 
a maintenance inspection on a V-band clamp located on the engine 
exhaust duct shroud. The clamp ends were touching (although the 
correct fastener torque had been applied), resulting in reduced 
clamp force on the flanges. We are issuing this AD to prevent 
vibration in the duct shroud and fretting of the V-band clamp and 
flanges, which could result in cracking of the flanges and 
consequent release of hot exhaust gases from the engine tailpipe and 
damage to adjacent structure. This situation could trigger the fire 
warning system and result in an in-flight emergency, such as the 
flightcrew shutting down the engine and activating the fire 
suppression system.

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.

Inspection/Investigative and Corrective Actions

    (f) Within 5,000 flight hours after the effective date of this 
AD: Inspect to determine the part number (P/N) of the V-band clamps 
on the engine exhaust duct shroud in accordance with the 
Accomplishment Instructions of Bombardier Service Bulletin 84-78-01, 
Revision `A,' dated September 15, 2005. For any V-band clamp having 
P/N VC1642A-2030-A or VC1642A-1875-A, before further flight, 
determine the manufacturer's date and do all applicable related 
investigative and corrective actions (including inspecting the 
flange of the shroud assemblies for discrepancies), by accomplishing 
all the actions specified in the Accomplishment Instructions of the 
service bulletin; except as provided by paragraph (g) of this AD. Do 
all applicable related investigative and corrective actions before 
further flight.
    (g) If, during the accomplishment of the corrective actions 
required by paragraph (f) of this AD, the service bulletin specifies 
contacting the manufacturer for repair instructions, before further 
flight, repair in accordance with a method approved by either the 
Manager, New York Aircraft Certification Office (ACO), FAA; or 
Transport Canada Civil Aviation (TCCA) (or its delegated agent).

Actions Accomplished According to Previous Issue of Service Bulletin

    (h) Actions accomplished before the effective date of this AD 
according to Bombardier Service Bulletin 84-78-01, dated March 22, 
2005, are considered acceptable for compliance with the 
corresponding actions specified in paragraph (f) of this AD.

Parts Installation

    (i) As of the effective date of this AD, no person may install a 
V-band clamp, P/N VC1642A-2030-A or VC1642A-1875-A, with a 
manufacturer batch stamp dated before ``08-02,'' on any airplane.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, New York ACO, 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

    (k) Canadian airworthiness directive CF-2006-06, dated April 4, 
2006, also addresses the subject of this AD.

Material Incorporated by Reference

    (l) You must use Bombardier Service Bulletin 84-78-01, Revision 
`A,' dated September 15, 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 February 2, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E7-2411 Filed 2-13-07; 8:45 am]
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