[Federal Register: May 19, 2004 (Volume 69, Number 97)]
[Proposed Rules]
[Page 28863-28865]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19my04-16]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2003-NM-285-AD]
RIN 2120-AA64
Airworthiness Directives; Bombardier Model DHC-8-101, -102, -103,
-106, -201, -202, -301, -311, and -315 Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes the adoption of a new airworthiness
directive (AD) that is applicable to certain Bombardier Model DHC-8-
101, -102, -103, -106, -201, -202, -301, -311, and -315 airplanes. This
proposal would require an inspection of the fuel tube assembly of the
auxiliary power unit (APU) for clearance from adjacent components; and
inspecting the fuel tube assembly and the bleed air duct shroud for
discrepancies (insufficient clearance, nicks, dents, chafing, or other
damage); and related investigative and corrective actions if necessary.
This proposal also would require relocating certain support clamps on
the APU fuel tube assembly. This action is necessary to prevent a fuel
leak caused by chafing of the APU fuel tube assembly, which could
result in fire in the center wing area. This action is intended to
address the identified unsafe condition.
DATES: Comments must be received by June 18, 2004.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 2003-NM-285-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9 a.m. and 3 p.m., Monday through Friday, except
Federal holidays. Comments may be submitted via fax to (425) 227-1232.
Comments may also be sent via the Internet using the following address:
9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must
contain ``Docket No. 2003-NM-285-AD'' in the subject line and need not
be submitted in triplicate. Comments sent via the Internet as attached
electronic files must be formatted in Microsoft Word 97 or 2000 or
ASCII text.
The service information referenced in the proposed rule may be
obtained from Bombardier, Inc., Bombardier Regional Aircraft Division,
123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. This
information may be examined at the FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington; or at the FAA, New York
Aircraft Certification Office, 1600 Stewart Avenue, suite 410,
Westbury, New York.
FOR FURTHER INFORMATION CONTACT: Sarbhpreet Singh Sawhney, 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) 228-7340; fax (516) 794-5531.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the
proposed rule by submitting such written data, views, or arguments as
they may desire. Communications shall identify the Rules Docket number
and be submitted in triplicate to the address specified above. All
communications received on or before the closing date for comments,
specified above, will be considered before taking action on the
proposed rule. The proposals contained in this action may be changed in
light of the comments received.
Submit comments using the following format:
Organize comments issue-by-issue. For example, discuss a
request to change the compliance time and a request to change the
service bulletin reference as two separate issues.
For each issue, state what specific change to the proposed
AD is being requested.
Include justification (e.g., reasons or data) for each
request.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed rule. All
comments submitted will be available, both before and after the closing
date for comments, in the Rules Docket for examination by interested
persons. A report summarizing each FAA-public contact concerned with
the substance of this proposal will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this action must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 2003-NM-285-AD.'' The postcard will be date stamped
and returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules
Docket No. 2003-NM-285-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
Transport Canada Civil Aviation (TCCA), which is the airworthiness
authority for Canada, notified the FAA that an unsafe condition may
exist on certain Bombardier Model DHC-8-101, -102, -103, -106, -201, -
202, -301, -311, and -315 airplanes. TCCA advises that an investigation
of a fuel leak revealed chafing of the fuel tube assembly for the
auxiliary power unit (APU). This fuel tube assembly is on the bleed air
duct shroud, which is located in the center wing area where it is
attached to a fairlead by two support clamps. It is possible that
incorrect location of these support clamps may result in insufficient
clearance between the fuel line and the bleed air duct, and/or between
the fuel line and the gust lock cable. If there is insufficient
clearance, the APU feed tube assembly can chafe, which could result in
a fuel leak and possible fire in the center wing area.
Explanation of Relevant Service Information
Bombardier has issued Service Bulletin 8-49-19, Revision A, dated
July 7, 2003, which describes procedures for doing a visual inspection
of the APU fuel tube assembly. This inspection includes examining the
routing of the fuel tube assembly to ensure that the tube has
sufficient clearance between the shroud of the bleed air duct and the
gust lock cable; and inspecting the fuel tube assembly and the bleed
air duct shroud for other discrepancies such as nicks, dents, chafing,
or other damage. If the visual inspection shows no discrepancies, the
service bulletin specifies to relocate the clamps on the APU fuel tube
assembly. If the visual inspection shows discrepancies, the service
bulletin describes procedures for related investigative and corrective
actions before relocating the support clamps for the fuel tube
assembly. These related investigative and corrective actions include:
[[Page 28864]]
Blending out the damaged area and measuring the depth of
the reworked area.
For fuel tubes on which damage (nicks, chafing, or dents)
is within acceptable limits: Doing an eddy current or fluorescent
penetrant inspection for cracks. If cracks are found, or if the damage
is outside the acceptable limits specified in the service bulletin:
Reworking/repairing the tube assembly or replacing it with a new or
serviceable tube assembly.
Visually inspecting the replaced tube assembly for fuel
leakage after rework or repair.
Accomplishment of the actions specified in the service bulletin is
intended to adequately address the identified unsafe condition. TCCA
classified this service bulletin as mandatory and issued Canadian
airworthiness directive CF-2003-22, dated September 3, 2003, to ensure
the continued airworthiness of these airplanes in Canada.
FAA's Conclusions
These airplane models are manufactured in Canada and are type
certificated for operation in the United States under the provisions of
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and
the applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, TCCA has kept the FAA informed of
the situation described above. We have examined the findings of TCCA,
reviewed all available information, and determined that AD action is
necessary for products of this type design that are certificated for
operation in the United States.
Explanation of Requirements of Proposed Rule
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design registered
in the United States, the proposed AD would require accomplishment of
the actions specified in the service bulletin described previously.
Cost Impact
We estimate that up to 125 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 1 work
hour per airplane to accomplish the proposed actions, and that the
average labor rate is $65 per work hour. Based on these figures, the
cost impact of the proposed AD on U.S. operators is estimated to be
$8,125, or $65 per airplane.
The cost impact figure discussed above is based on assumptions that
no operator has yet accomplished any of the proposed requirements of
this AD action, and that no operator would accomplish those actions in
the future if this AD were not adopted. The cost impact figures
discussed in AD rulemaking actions represent only the time necessary to
perform the specific actions actually required by the AD. These figures
typically do not include incidental costs, such as the time required to
gain access and close up, planning time, or time necessitated by other
administrative actions.
Regulatory Impact
The regulations proposed herein 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. Therefore, it
is determined that this proposal would not have federalism implications
under Executive Order 13132.
For the reasons discussed above, I certify that 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) if promulgated, 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. A copy of the draft
regulatory evaluation prepared for this action is contained in the
Rules Docket. A copy of it may be obtained by contacting the Rules
Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new
airworthiness directive:
Bombardier, Inc. (Formerly de Havilland, Inc.): Docket 2003-NM-285-
AD.
Applicability: Model DHC-8-101, -102, -103, -106, -201, -202, -
301, -311, and -315 airplanes, serial number 003 through 585
inclusive; certificated in any category; with auxiliary power unit
(APU) installation per Standard Option Only (S.O.O.) 8155 or Change
Request (CR) 849SO08155.
Compliance: Required as indicated, unless accomplished
previously.
To prevent a fuel leak caused by chafing of the APU fuel tube
assembly, which could result in fire in the center wing area,
accomplish the following:
Inspection, Relocation and Related Investigative and Corrective Actions
(a) Within 6 months after the effective date of this AD: Do a
general visual inspection of the APU fuel tube assembly for
discrepancies. The inspection includes examining the routing of the
fuel tube assembly to ensure that the tube has sufficient clearance
between the shroud of the bleed air duct and the gust lock cable;
and inspecting the fuel tube assembly and the bleed air duct shroud
for other discrepancies such as nicks, dents, chafing, or other
damage. If the inspection shows no discrepancies, before further
flight, relocate the clamps on the fuel tube assembly. If the
inspection shows discrepancies, before further flight, do the
applicable related investigative and corrective actions, and
relocate the clamps on the fuel tube assembly. Accomplish all
actions per the Accomplishment Instructions of Bombardier Service
Bulletin 8-49-19, Revision A, dated July 7, 2003.
Note 1: For the purposes of this AD, a general visual inspection
is defined as: ``A visual examination of an interior or exterior
area, installation, or assembly to detect obvious damage, failure,
or irregularity. This level of inspection is made from within
touching distance unless otherwise specified. A mirror may be
necessary to enhance visual access to all exposed surfaces in the
inspection area. This level of inspection is made under normally
available lighting conditions such as daylight, hangar lighting,
flashlight, or droplight and may require removal or opening of
access panels or doors. Stands, ladders, or platforms may be
required to gain proximity to the area being checked.''
Inspections Accomplished Per Previous Issue of Service Bulletin
(b) Actions accomplished before the effective date of this AD
per Bombardier Service Bulletin 8-49-19, dated May 13, 2003, are
considered acceptable for compliance with the corresponding action
specified in this AD.
Alternative Methods of Compliance
(c) In accordance with 14 CFR 39.19, the Manager, New York
Aircraft Certification Office, FAA, is authorized to approve
alternative methods of compliance for this AD.
Note 2: The subject of this AD is addressed in Canada
airworthiness directive CF-2003-22, dated September 3, 2003.
[[Page 28865]]
Issued in Renton, Washington, on May 11, 2004.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 04-11290 Filed 5-18-04; 8:45 am]
BILLING CODE 4910-13-P