[Federal Register Volume 64, Number 171 (Friday, September 3, 1999)]
[Proposed Rules]
[Pages 48333-48335]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-23064]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 98-NM-335-AD]
RIN 2120-AA64
Airworthiness Directives; Bombardier Model DHC-8-101, -102, -103,
-106, -201, -202, -301, -311, and -315 Series 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 all Bombardier Model DHC-8-101, -
102, -103, -106, -201, -202, -301, -311, and -315 series airplanes.
This proposal would require repetitive detailed visual inspections and
high frequency eddy current inspections to detect cracking of the wing
upper skin and ladder plates at over wing access panels between certain
stations; and repair, if necessary. This proposal is prompted by
issuance of mandatory continuing airworthiness information by a foreign
civil airworthiness authority. The actions specified by the proposed AD
are intended to detect and correct fatigue cracking of the wing ladder
plates, which, if not corrected, could reduce the structural integrity
of the wing.
DATES: Comments must be received by October 4, 1999.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-114,
Attention: Rules Docket No. 98-NM-335-AD, 1601 Lind Avenue, SW.,
Renton, Washington 98055-4056. Comments may be inspected at this
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except
Federal holidays.
The service information referenced in the proposed rule may be
obtained from Bombardier, Inc., Bombardier Regional Aircraft Division,
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, Engine and Propeller
Directorate, New
[[Page 48334]]
York Aircraft Certification Office, 10 Fifth Street, Third Floor,
Valley Stream, New York.
FOR FURTHER INFORMATION CONTACT: Franco Pieri, Aerospace Engineer,
Airframe and Propulsion Branch, ANE-171, FAA, Engine and Propeller
Directorate, New York Aircraft Certification Office, 10 Fifth Street,
Third Floor, Valley Stream, New York 11581; telephone (516) 256-7526;
fax (516) 568-2716.
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 notice may be changed in
light of the comments received.
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 notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 98-NM-335-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. 98-NM-335-AD, 1601 Lind Avenue, SW., Renton, Washington
98055-4056.
Discussion
The Transport Canada Civil Aviation (TCCA), which is the
airworthiness authority for Canada, notified the FAA that an unsafe
condition may exist on all Bombardier Model DHC-8-101, -102, -103, -
106, -201, -202, -301, -311, and -315 series airplanes. The TCCA
advises that fatigue cracking of the wing ladder plate has been found
on DHC-8 series airplanes. This cracking has been attributed to
repeated fatigue load cycles. This condition, if not corrected, could
result in reduced structural integrity of the wing.
Explanation of Relevant Service Information
Bombardier has issued de Havilland Temporary Revision TR MTC-15,
dated September 18, 1998, of the de Havilland Maintenance Program
Manual PSM 1-8-7 (for Model DHC-8-100 series airplanes); de Havilland
Temporary Revision TR MTC 2-14, dated September 18, 1998, of the de
Havilland Maintenance Program Manual PSM 1-82-7 TC (for Model DHC-8-200
series airplanes); and de Havilland Temporary Revision TR MTC 3-14,
dated September 18, 1998, of the de Havilland Maintenance Program
Manual PSM 1-83-7 TC (for Model DHC-8-300 series airplanes). These
temporary revisions describe procedures for repetitive detailed visual
inspections and high frequency eddy current (HFEC) inspections to
detect cracking of the wing upper skin and ladder plates at over wing
access panels between station YW42.00 and YW171.20.
Bombardier also has issued de Havilland Airworthiness Limitations
List Temporary Revision TR AWL-59, dated September 10, 1998, of the de
Havilland Maintenance Program Manual PSM 1-8-7 (for Model DHC-8-100
series airplanes); de Havilland Airworthiness Limitations List
Temporary Revision TR AWL2-11, dated September 10, 1998, of de
Havilland Maintenance Program Manual PSM 1-82-7 (for Model DHC-8-200
series airplanes); and de Havilland Airworthiness Limitations List
Temporary Revision TR AWL3-64, dated September 10, 1998, of de
Havilland Maintenance Program Manual PSM 1-83-7 (for Model DHC-8-300
series airplanes). These temporary revisions describe the compliance
times associated with the repetitive detailed visual inspections and
HFEC inspections described previously.
Accomplishment of the actions specified in the temporary revisions
is intended to adequately address the identified unsafe condition. The
TCCA classified these temporary revisions as mandatory and issued
Canadian airworthiness directive CF-98-30, dated August 31, 1998, in
order to assure 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, the TCCA has kept the FAA informed
of the situation described above. The FAA has examined the findings of
the 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 temporary revisions described previously,
except as discussed below.
Differences Between Proposed Rule and Service Information
Operators should note that, although the Canadian airworthiness
directive and the temporary revisions specify that the manufacturer may
be contacted for disposition of certain repair conditions, this
proposal would require the repair of those conditions to be
accomplished in accordance with a method approved by the FAA, or the
TCCA (or its delegated agent). In light of the type of repair that
would be required to address the identified unsafe condition, and in
consonance with existing bilateral airworthiness agreements, the FAA
has determined that, for this proposed AD, a repair approved by either
the FAA or the TCCA would be acceptable for compliance with this
proposed AD.
Operators also should note that, although the Canadian
airworthiness directive affects Bombardier Model DHC-8-314 series
airplanes, Bombardier Model DHC-8-314 series airplanes are not type
certificated in the United States. Therefore, the proposed AD does not
affect those airplanes.
Cost Impact
The FAA estimates that 166 airplanes of U.S. registry would be
affected by this proposed AD, that it would take approximately 40 work
hours per airplane to accomplish the proposed inspections, and that the
average labor rate is $60 per work hour. Based on these figures, the
cost impact of the proposed AD on U.S. operators is estimated to be
$398,400, or $2,400 per airplane, per inspection cycle.
The cost impact figure discussed above is based on assumptions that
no
[[Page 48335]]
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.
Regulatory Impact
The regulations proposed herein would not have substantial direct
effects 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, in
accordance with Executive Order 12612, it is determined that this
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
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 98-NM-335-
AD.
Applicability: All Model DHC-8-101, -102, -103, -106, -201, -
202, -301, -311, and -315 series airplanes, certificated in any
category.
Note 1: This AD applies to each airplane identified in the
preceding applicability provision, regardless of whether it has been
modified, altered, or repaired in the area subject to the
requirements of this AD. For airplanes that have been modified,
altered, or repaired so that the performance of the requirements of
this AD is affected, the owner/operator must request approval for an
alternative method of compliance in accordance with paragraph (d) of
this AD. The request should include an assessment of the effect of
the modification, alteration, or repair on the unsafe condition
addressed by this AD; and, if the unsafe condition has not been
eliminated, the request should include specific proposed actions to
address it.
Compliance: Required as indicated, unless accomplished
previously.
To detect and correct fatigue cracking of the wing ladder plates,
which if not corrected, could reduce the structural integrity of the
wing, accomplish the following:
Inspection for DHC-8-100 and -300 Series Airplanes
(a) At the applicable compliance time listed in paragraph
(a)(1), (a)(2), or (a)(3) of this AD, perform a detailed visual
inspection to detect cracking of the skin and a high frequency eddy
current (HFEC) inspection of the ladder plates at over wing access
panels between station YW42.00 and YW171.20, in accordance with de
Havilland Temporary Revision TR MTC-15, dated September 18, 1998, of
the de Havilland Maintenance Program Manual PSM-1-8-7 TC (for Model
DHC-8-100 series airplanes); or de Havilland Temporary Revision TR
MTC 3-14, dated September 18, 1998, of the de Havilland Maintenance
Program Manual PSM 1-83-7 (for Model DHC-8-300 series airplanes); as
applicable. Repeat the inspections thereafter at intervals not to
exceed 10,000 flight cycles.
(1) For airplanes that have accumulated 5,000 or fewer total
flight cycles as of the effective date of this AD, accomplish the
inspection prior to the accumulation of 10,000 total flight cycles.
(2) For airplanes that have accumulated more than 5,000 total
flight cycles, but fewer than 38,501 total flight cycles as of the
effective date of this AD, accomplish the inspection prior to the
accumulation of [5,522 + (0.8955 x N Accumulated)] total cycles. ``N
Accumulated'' is defined as the total number of flight cycles as of
the effective date of this AD.
(3) For airplanes that have accumulated 38,501 or more total
flight cycles as of the effective date of this AD, accomplish the
inspection within 1,500 flight cycles after the effective date of
this AD.
Note 2: For the purposes of this AD, a detailed visual
inspection is defined as: ``An intensive visual examination of a
specific structural area, system, installation, or assembly to
detect damage, failure, or irregularity. Available lighting is
normally supplemented with a direct source of good lighting at
intensity deemed appropriate by the inspector. Inspection aids such
as mirror, magnifying lenses, etc., may be used. Surface cleaning
and elaborate access procedures may be required.''
Inspection for DHC-8-200 Series Airplanes
(b) At the applicable compliance time listed in paragraph (b)(1)
or (b)(2) of this AD, perform a detailed visual inspection of the
skin and an HFEC inspection to detect cracking of the ladder plates
at over wing access panels between station YW42.00 and YW171.20, in
accordance with de Havilland Temporary Revision TR MTC 2-14, dated
September 18, 1998, of the de Havilland Maintenance Program Manual
PSM 1-82-7. Repeat the inspections thereafter at intervals not to
exceed 10,000 flight cycles.
(1) For airplanes that have accumulated 5,000 or fewer total
flight cycles as of the effective date of this AD, accomplish the
inspection prior to the accumulation of 10,000 total flight cycles.
(2) For airplanes that have accumulated more than 5,000 total
flight cycles, but fewer than 38,501 total flight cycles as of the
effective date of this AD, accomplish the inspection prior to the
accumulation of [5,522 + (0.8955 x N Accumulated)] total cycles,
where ``N Accumulated'' is defined as the total number of flight
cycles as of the effective date of this AD.
Repair
(c) If any crack is detected during any inspection required by
this AD, prior to further flight, repair in accordance with a method
approved by the Manager, New York Aircraft Certification Office
(ACO), FAA, Engine and Propeller Directorate; or the Transport
Canada Civil Aviation (TCCA) (or its delegated agent). For a repair
method to be approved by the Manager, New York ACO, as required by
this paragraph, the Manager's approval letter must specifically
reference this AD.
Alternative Methods of Compliance
(d) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, New York Aircraft Certification
Office (ACO), FAA, Engine and Propeller Directorate. Operators shall
submit their requests through an appropriate FAA Principal
Maintenance Inspector, who may add comments and then send it to the
Manager, New York ACO.
Note 3: Information concerning the existence of approved
alternative methods of compliance with this AD, if any, may be
obtained from the New York ACO.
Special Flight Permits
(e) Special flight permits may be issued in accordance with
sections 21.197 and 21.199 of the Federal Aviation Regulations (14
CFR 21.197 and 21.199) to operate the airplane to a location where
the requirements of this AD can be accomplished.
Note 4: The subject of this AD is addressed in Canadian
airworthiness directive CF-98-30, dated August 31, 1998.
Issued in Renton, Washington, on August 30, 1999.
Vi L. Lipski,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 99-23064 Filed 9-2-99; 8:45 am]
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