AD 2007-04-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bombardier Inc. | DHC-8-400 | Airworthiness Directives; Bombardier Model DHC-8-400 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-401 | Airworthiness Directives; Bombardier Model DHC-8-400 Series Airplanes |
| aircraft | Bombardier Inc. | DHC-8-402 | Airworthiness Directives; Bombardier Model DHC-8-400 Series Airplanes |
Unsafe Condition
Reduced clamp force on the flanges due to V-band clamp ends touching, leading to vibration, fretting, and potential cracking of the flanges. This could result in the release of hot exhaust gases and damage to adjacent structure, triggering the fire warning system and an in-flight emergency.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Inspect to determine the manufacturer's date of certain V-band clamps on the engine exhaust shroud assembly. Perform investigative/corrective actions if necessary to address discrepancies found during the inspection.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Bombardier Model DHC-8-400 series airplanes with specific V-band clamps on the engine exhaust shroud assembly.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
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.
Document Text
Show stored source text (verify against official source)
[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 [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: E7-2411]
-----------------------------------------------------------------------
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.
-----------------------------------------------------------------------
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 <a href="http://dms.dot.gov">http://dms.dot.gov</a> 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 <a href="http://dms.dot.gov">http://dms.dot.gov</a> 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 <a href="http://dms.dot.gov">http://dms.dot.gov</a>; 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 <a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
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]
BILLING CODE 4910-13-P
Source: Official FAA Source ↗
Retrieved: Apr 6, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.