[Federal Register: June 10, 2008 (Volume 73, Number 112)]
[Proposed Rules]
[Page 32659-32662]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr10jn08-7]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2008-0636; Directorate Identifier 2007-NM-324-AD]
RIN 2120-AA64
Airworthiness Directives; ATR Model ATR42-200, -300, and -320
Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the
products listed above. This proposed AD results from mandatory
continuing airworthiness information (MCAI) originated by an aviation
authority of another country to identify and correct an unsafe
condition on an aviation product. The MCAI describes the unsafe
condition as:
One ATR 42-300 experienced a collapse of the Right (RH) Main
Landing Gear (MLG) when taxiing, caused by failure of the side brace
assembly. Investigations revealed a crack propagation that occurred
from a corrosion pit, in a very high stressed area of the upper arm.
* * *
* * * * *
The unsafe condition is cracking of the upper arms of the secondary
side brace assemblies of the MLG, which could result in collapse of the
MLG during takeoff or landing, damage to the airplane, and possible
injury to the flightcrew and passengers. The proposed AD would require
actions that are intended to address the unsafe condition described in
the MCAI.
DATES: We must receive comments on this proposed AD by July 10, 2008.
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
Fax: (202) 493-2251.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
Hand Delivery: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-40, 1200 New
Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday
through Friday, except Federal holidays.
Examining the AD Docket
You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Operations office
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this proposed AD, the regulatory
evaluation, any comments received, and other information. The street
address for the Docket Operations office (telephone (800) 647-5527) is
in the ADDRESSES section. Comments will be available in the AD docket
shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Tom Rodriguez, Aerospace Engineer,
International Branch, ANM-116, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425)
227-1137; fax (425) 227-1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0636;
Directorate Identifier 2007-NM-324-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD based on those comments.
We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this proposed AD.
Discussion
The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Community, has issued EASA
Airworthiness Directive 2007-0263, dated October 3, 2007 (referred to
after this as ``the MCAI''), to correct an unsafe condition for the
specified products. The MCAI states:
ONE ATR 42-300 experienced a collapse of the Right (RH) Main
Landing Gear (MLG) when taxiing, caused by failure of the side brace
assembly. Investigations revealed a crack propagation that occurred
from a corrosion pit, in a very high stressed area of the upper arm.
Dimensions of the corrosion pit were lower than the minimum defect
size that can be detected by usual inspection means used during
landing gear overhaul. The superseded EASA (European Aviation Safety
Agency) Airworthiness Directive (AD) 2007-0112 was issued to require
repetitive inspections on affected high stressed areas on MLG side
brace assemblies for crack detection and to replace the affected
side brace assembly if any defect was found.
Since the issuance of [EASA] AD 2007-0112, a modification of
[the] side brace upper arm has been developed as terminating action.
However, production non-conformity of the inspection tool was
discovered.
In order to correct the discrepancy of the initial tool, new
inspection tool components have been manufactured and the Service
Bulletin (SB) Messier Dowty 631-32-191 has been updated to revision
2 accordingly. This directive mandates re-inspection of MLG side
brace assemblies previously inspected in accordance with revision 1
of the Messier Dowty SB 631-32-191 and reduces the inspection
interval initially proposed in [EASA] AD 2007-0112 in order to
maintain the same level of confidence.
* * * * *
The unsafe condition is cracking of the upper arms of the secondary
side brace assemblies of the MLG, which could result in collapse of the
MLG during takeoff or landing, damage to the airplane, and possible
injury to the flightcrew and passengers. You may obtain further
information by examining the MCAI in the AD docket.
Relevant Service Information
Messier-Dowty has issued Special Inspection Service Bulletin 631-
32-191, Revision 2, dated August 30, 2007, and Service Bulletin 631-32-
194, dated June 6, 2007. ATR has issued Service Bulletin ATR42-32-0092,
dated June 25, 2007. ATR has also issued Technical Instruction ATR42-
07-01, dated February 5, 2007. The actions described in this service
information are intended to correct the unsafe condition identified in
the MCAI.
FAA's Determination and Requirements of This Proposed AD
This product has been approved by the aviation authority of another
country, and is approved for operation in the United States. Pursuant
to our bilateral agreement with the State of Design Authority, we have
been notified of the unsafe condition described in the MCAI and service
information referenced above. We are proposing this AD because we
evaluated all pertinent information and determined an unsafe condition
exists and is likely to exist or develop on other products of the same
type design.
[[Page 32660]]
Differences Between This AD and the MCAI or Service Information
We have reviewed the MCAI and related service information and, in
general, agree with their substance. But we might have found it
necessary to use different words from those in the MCAI to ensure the
AD is clear for U.S. operators and is enforceable. In making these
changes, we do not intend to differ substantively from the information
provided in the MCAI and related service information.
We might also have proposed different actions in this AD from those
in the MCAI in order to follow FAA policies. Any such differences are
highlighted in a NOTE within the proposed AD.
Costs of Compliance
Based on the service information, we estimate that this proposed AD
would affect about 31 products of U.S. registry. We also estimate that
it would take about 35 work-hours per product to comply with the basic
requirements of this proposed AD. The average labor rate is $80 per
work-hour. Required parts would cost about $0 per product. Based on
these figures, we estimate the cost of the proposed AD on U.S.
operators to be $86,800, or $2,800 per product.
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 determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD 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.
For the reasons discussed above, I certify 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. 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 proposed AD and placed it in the AD docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 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. The FAA amends Sec. 39.13 by adding the following new AD:
ATR--GIE Avions de Transport Regional (Formerly Aerospatiale):
Docket No. FAA-2008-0636; Directorate Identifier 2007-NM-324-AD.
Comments Due Date
(a) We must receive comments by July 10, 2008.
Affected ADs
(b) None.
Applicability
(c) This AD applies to ATR Model ATR42-200, -300, and -320
airplanes, certificated in any category; excluding airplanes on
which ATR Modification 8463 has been done.
Subject
(d) Air Transport Association (ATA) of America Code 32: Landing
gear.
Reason
(e) The mandatory continuing airworthiness information (MCAI)
states:
One ATR 42-300 experienced a collapse of the Right (RH) Main
Landing Gear (MLG) when taxiing, caused by failure of the side brace
assembly. Investigations revealed a crack propagation that occurred
from a corrosion pit, in a very high stressed area of the upper arm.
Dimensions of the corrosion pit were lower than the minimum defect
size that can be detected by usual inspection means used during
landing gear overhaul. The superseded EASA (European Aviation Safety
Agency) Airworthiness Directive (AD) 2007-0112 was issued to require
repetitive inspections on affected high stressed areas on MLG side
brace assemblies for crack detection and to replace the affected
side brace assembly if any defect was found.
Since the issuance of [EASA] AD 2007-0112, a modification of
[the] side brace upper arm has been developed as terminating action.
However, production non-conformity of the inspection tool was
discovered.
In order to correct the discrepancy of the initial tool, new
inspection tool components have been manufactured and the Service
Bulletin (SB) Messier Dowty 631-32-191 has been updated to revision
2 accordingly. This directive mandates re-inspection of MLG side
brace assemblies previously inspected in accordance with revision 1
of the Messier Dowty SB 631-32-191 and reduces the inspection
interval initially proposed in [EASA] AD 2007-0112 in order to
maintain the same level of confidence.
* * * * *
The unsafe condition is cracking of the upper arms of the
secondary side brace assemblies of the MLG, which could result in
collapse of the MLG during takeoff or landing, damage to the
airplane, and possible injury to the flightcrew and passengers.
Actions and Compliance
(f) For MLG side brace assemblies with part number (P/N)
D22710000, without suffix ``-9'': Unless already done, do the
following actions.
(1) For airplanes on which the MLG side brace assemblies have
not been inspected as of the effective date of this AD, in
accordance with the Accomplishment Instructions of Messier-Dowty
Service Bulletin 631-32-191, Revision 1, dated February 26, 2007:
Perform the initial eddy current inspection for cracking of the MLG
side brace, in accordance with the Accomplishment Instructions of
Messier-Dowty Special Inspection Service Bulletin 631-32-191,
Revision 2, dated August 30, 2007, at the applicable time specified
in Table 1 of this AD. Unless otherwise specified, the flight cycles
and times indicated in Table 1 of this AD must be interpreted as
total flight cycles since overhaul, or time since overhaul, and as
total flight cycles since new or time since manufacture for side
brace assemblies that have not undergone any overhaul yet.
[[Page 32661]]
Table 1.--Compliance Times
------------------------------------------------------------------------
For a MLG side brace assembly with the
total flight cycles since new or total
flight cycles since overhaul specified Do the initial inspection at
below as of the effective date of this the time specified below--
AD--
------------------------------------------------------------------------
More than 8,000 flight cycles.......... Within 500 flight cycles after
the effective date of this AD.
5,000 or more total flight cycles, but Within 1,000 flight cycles
not more than 8,000 total flight after the effective date of
cycles. this AD or before accumulating
8,500 flight cycles, whichever
occurs first.
Less than 5,000 flight cycles.......... Within 2,000 flight cycles
after the effective date of
this AD or before accumulating
6,000 flight cycles, whichever
occurs first.
------------------------------------------------------------------------
(2) For airplanes on which the MLG side brace assemblies have
been inspected as of the effective date of this AD, in accordance
with the Accomplishment Instructions of Messier-Dowty Service
Bulletin 631-32-191, Revision 1, dated February 26, 2007: Within
1,000 flight cycles after the last inspection or within 200 flight
cycles after the effective date of this AD, whichever occurs later,
perform an eddy current inspection for cracking of the MLG side
brace, in accordance with the Accomplishment Instructions of
Messier-Dowty Special Inspection Service Bulletin 631-32-191,
Revision 2, dated August 30, 2007.
(3) After accomplishment of the inspection required by paragraph
(f)(1) or (f)(2) of this AD, repeat the inspection at intervals not
to exceed 2,600 flight cycles in accordance with the Accomplishment
Instructions of Messier-Dowty Special Inspection Service Bulletin
631-32-191, Revision 2, dated August 30, 2007.
(4) If any crack is found during any inspection required by
paragraphs (f)(1), (f)(2) and (f)(3) of this AD, before further
flight, replace the affected side brace in accordance with the
Accomplishment Instructions of Messier-Dowty Special Inspection
Service Bulletin 631-32-191, Revision 2, dated August 30, 2007.
(5) At the applicable time specified in paragraph (f)(5)(i) or
(f)(5)(ii) of this AD: Inspect for cracking, corrosion, and defects
of the MLG side brace assemblies with P/N D22710000, without suffix
``-9'', in accordance with the Accomplishment Instructions of
Messier Dowty Service Bulletin 631-32-194, dated June 6, 2007.
(i) For airplanes having side brace assemblies on which Messier-
Bugatti Service Bulletin 631-32-072 has not been incorporated:
Before accumulating 16,000 total flight cycles or within 8 years
after the effective date of this AD, whichever occurs first.
(ii) For airplanes having side brace assemblies on which
Messier-Bugatti Service Bulletin 631-32-072 has been incorporated:
Before accumulating 19,000 total flight cycles or within 8 years
after the effective date of this AD, whichever occurs first.
(6) If no cracking, corrosion, or defect is found during any
inspection required by paragraph (f)(5) of this AD, before further
flight, modify and re-identify (by adding a suffix ``-9'' to P/N
D22710000) the MLG side brace assemblies in accordance with the
Accomplishment Instructions of ATR Service Bulletin ATR42-32-0092,
dated June 25, 2007.
(7) If any cracking, corrosion, or defect is found during any
inspection required by paragraph (f)(5) of this AD, before further
flight, replace the discrepant MLG side brace assembly with a
modified and re-identified MLG side brace assembly in accordance
with the Accomplishment Instructions of ATR Service Bulletin ATR42-
32-0092, dated June 25, 2007.
FAA AD Differences
Note: This AD differs from the MCAI and/or service information
as follows: Although the MCAI or service information allows further
flight if a crack is found during compliance with the required
inspections, this AD requires that you repair the crack before
further flight.
Other FAA AD Provisions
(g) The following provisions also apply to this AD:
(1) Alternative Methods of Compliance (AMOCs): The Manager,
International Branch, ANM-116, has the authority to approve AMOCs
for this AD, if requested using the procedures found in 14 CFR
39.19. Send information to ATTN: Tom Rodriguez, Aerospace Engineer,
International Branch, ANM-116, Transport Airplane Directorate, FAA,
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone
(425) 227-1137; fax (425) 227-1149. Before using any approved AMOC
on any airplane to which the AMOC applies, notify your appropriate
principal inspector (PI) in the FAA Flight Standards District Office
(FSDO), or lacking a PI, your local FSDO.
(2) Airworthy Product: For any requirement in this AD to obtain
corrective actions from a manufacturer or other source, use these
actions if they are FAA-approved. Corrective actions are considered
FAA-approved if they are approved by the State of Design Authority
(or their delegated agent). You are required to assure the product
is airworthy before it is returned to service.
(3) Reporting Requirements: For any reporting requirement in
this AD, under the provisions of the Paperwork Reduction Act, the
Office of Management and Budget (OMB) has approved the information
collection requirements and has assigned OMB Control Number 2120-
0056.
Related Information
(h) Refer to MCAI EASA Airworthiness Directive 2007-0263, dated
October 3, 2007, and the service information specified in Table 2 of
this AD, for related information.
Table 2.--Service Information
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Service Bulletin Revision Date
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ATR Service Bulletin ATR 42-32-0092...... Original.................... June 25, 2007.
ATR Technical Instruction ATR 42 ATR 42- Original.................... February 5, 2007.
07-01.
Messier-Dowty Service Bulletin 631-32-194 Original.................... June 6, 2007.
Messier-Dowty Special Inspection Service 2........................... August 30, 2007.
Bulletin 631-32-191.
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[[Page 32662]]
Issued in Renton, Washington, on June 3, 2008.
Michael J. Kaszycki,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. E8-12934 Filed 6-9-08; 8:45 am]
BILLING CODE 4910-13-P