[Federal Register: July 21, 2005 (Volume 70, Number 139)]
[Proposed Rules]
[Page 42003-42005]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr21jy05-20]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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[[Page 42003]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2005-21909; Directorate Identifier 2005-NM-059-AD]
RIN 2120-AA64
Airworthiness Directives; Aerospatiale Model ATR72 Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for certain Aerospatiale Model ATR72 airplanes. This proposed AD would
require a one-time general visual inspection for contamination of the
surface of the upper arms of the main landing gear (MLG) secondary side
brace assemblies; and repetitive eddy current inspections for cracking
of the upper arms, and related specified and corrective actions if
necessary. This proposed AD also would mandate eventual replacement of
aluminum upper arms with steel upper arms, which would end the
repetitive inspections. This proposed AD is prompted by two reports of
rupture of the upper arm of the MLG secondary side brace due to fatigue
cracking. We are proposing this AD to prevent 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.
DATES: We must receive comments on this proposed AD by August 22, 2005.
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD.
DOT Docket Web site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide rulemaking Web site: Go to http://www.regulations.gov
and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility, U.S. Department of
Transportation, 400 Seventh Street SW., Nassif Building, room PL-401,
Washington, DC 20590.
By fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m.
and 5 p.m., Monday through Friday, except Federal holidays.
For service information identified in this proposed AD, contact
Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France.
You can examine the contents of this 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., room PL-401,
on the plaza level of the Nassif Building, Washington, DC. This docket
number is FAA-2005-21909; the directorate identifier for this docket is
2005-NM-059-AD.
FOR FURTHER INFORMATION CONTACT: Tom Rodriguez, Aerospace Engineer,
International Branch, ANM-116, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
227-1137; fax (425) 227-1149.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any relevant written data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2005-21909;
Directorate Identifier 2005-NM-059-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the proposed AD. We will
consider all comments submitted by the closing date and may amend the
proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of our
docket Web site, anyone can find and read the comments in any of our
dockets, including the name of the individual who sent the comment (or
signed the comment on behalf of an association, business, labor union,
etc.). You can review the DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
can visit http://dms.dot.gov.
Examining the Docket
You can examine the 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 DOT
street address stated in the ADDRESSES section. Comments will be
available in the AD docket shortly after the Docket Management System
(DMS) receives them.
Discussion
The Direction G[eacute]n[eacute]rale de l'Aviation Civile (DGAC),
which is the airworthiness authority for France, notified us that an
unsafe condition may exist on certain Aerospatiale Model ATR72
airplanes. The DGAC advises that there were two reports of rupture of
the upper arm of the main landing gear (MLG) secondary side brace
assembly. Fatigue cracking has been determined to be the cause of the
ruptures. This cracking, if not corrected, could result in collapse of
the MLG during takeoff or landing, damage to the airplane, and possible
injury to the flightcrew and passengers.
Relevant Service Information
Messier-Dowty has issued Special Inspection Service Bulletin 631-
32-178, Revision 1, dated September 30, 2004. The service bulletin
describes procedures for, among other things, a one-time general visual
inspection for contamination of the surface of the upper arms of the
MLG secondary side brace assemblies, and an eddy current inspection for
cracking of the upper arms. The service bulletin also recommends
sending an inspection report to Messier-Dowty.
Aerospatiale has issued Avions de Transport Regional Service
Bulletin ATR72-32-1046, Revision 1, dated October 7, 2004. The service
bulletin
[[Page 42004]]
contains no Accomplishment Instructions, but describes procedures for
replacing the upper arms of the MLG secondary side brace assemblies.
The service bulletin refers to Messier-Dowty Service Bulletin 631-32-
183, dated October 6, 2004, as the source of service information for
accomplishing the replacement. Service Bulletin 631-32-183 describes
procedures for replacing aluminum upper arms of the MLG secondary side
brace assemblies with steel upper arms, and engraving a new suffix on
the identification plate on the assembly.
Accomplishing the actions specified in the service information is
intended to adequately address the unsafe condition. The DGAC mandated
the service information and issued French airworthiness directive F-
2004-164, dated October 13, 2004, to ensure the continued airworthiness
of these airplanes in France.
The French airworthiness directive refers to Messier-Bugatti
Service Bulletin 631-32-085, dated August 21, 1992, as the source of
service information for replacing the press-fitted ball cages of the
lower and upper arms of the MLG secondary side brace assemblies with
ball cages that are shrink-fitted and bonded with adhesive. For
airplanes on which this replacement has been accomplished, the
compliance time for the replacement of the aluminum upper arms is
extended.
FAA's Determination and Requirements of the Proposed AD
This airplane model is manufactured in France and is 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 DGAC has kept the FAA informed
of the situation described above. We have examined the DGAC's findings,
evaluated all pertinent information, and determined that we need to
issue an AD for products of this type design that are certificated for
operation in the United States.
Therefore, we are proposing this AD, which would require
accomplishing the actions specified in Avions de Transport Regional
Service Bulletin ATR72-32-1046, Revision 1; Messier-Dowty Special
Inspection Service Bulletin 631-32-178, Revision 1; and Messier-Dowty
Service Bulletin 631-32-183; described previously; except as discussed
under ``Differences Between the Proposed AD and Messier-Dowty Special
Inspection Service Bulletin 631-32-178.'' In addition, this proposed AD
would require, for replacement of aluminum upper arms, an eddy current
inspection and investigative or corrective actions. Replacement with
steel arms would end the repetitive inspections, and replacement with
aluminum arms would require repeating the eddy current inspections.
Differences Among Proposed AD, French Airworthiness Directive, and
Messier-Dowty Service Information
Although the French airworthiness directive requires replacing any
defective upper arm of the MLG secondary side brace assemblies with a
new or serviceable aluminum arm, or a new steel arm, there are no
procedures specified in Service Bulletin 631-32-183 for replacing the
defective arm with an aluminum arm. The service bulletin does reference
the ATR Component Maintenance Manual (CMM), Chapter 32-18-41, Revision
3, dated September 30, 2002, for procedures for replacing the affected
arm with a new steel arm. Therefore, this proposed AD will reference
the CMM for procedures for replacement of any defective aluminum upper
arm with a new or serviceable aluminum upper arm. Chapter 32-18-41
provides procedures for replacement of affected upper arms with either
steel or aluminum upper arms. This difference has been coordinated with
the DGAC.
Special Inspection Service Bulletin 631-32-178, Revision 1,
recommends sending an inspection report to Messier-Dowty, but this
proposed AD does not contain that requirement.
Special Inspection Service Bulletin 631-32-178, Revision 1, refers
only to a ``visual inspection'' for contamination of the surface. We
have determined that the procedures in the service bulletin should be
described as a ``general visual inspection.'' A note has been included
in this AD to define this type of inspection.
Costs of Compliance
This proposed AD would affect about 18 airplanes of U.S. registry.
The proposed initial and repetitive inspections would take about 1
work hour per airplane, at an average labor rate of $65 per work hour.
Based on these figures, the estimated cost of the proposed inspections
for U.S. operators is $1,170, or $65 per airplane, per inspection
cycle.
The proposed replacement would take about 4 work hours per airplane
(2 work hours per upper arm), at an average labor rate of $65 per work
hour. Required parts would cost about $4,948 per airplane ($2,474 per
upper arm). Based on these figures, the estimated cost of the proposed
replacement for U.S. operators is $93,744, or $5,208 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 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 that the 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. 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, 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:
[[Page 42005]]
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
airworthiness directive (AD):
Aerospatiale: Docket No. FAA-2005-21909; Directorate Identifier
2005-NM-059-AD.
Comments Due Date
(a) The Federal Aviation Administration must receive comments on
this AD action by August 22, 2005.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Aerospatiale Model ATR72-101, -102, -201,
-202, -211, -212, and -212A airplanes, certificated in any category;
except airplanes that have received ATR Modification 5522 in
production.
Unsafe Condition
(d) This AD was prompted by two reports of rupture of the upper
arm of the main landing gear (MLG) secondary side brace assembly due
to fatigue cracking. We are issuing this AD to prevent 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.
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.
Inspections
(f) At the latest of the times specified in paragraphs (f)(1),
(f)(2), and (f)(3) of this AD: Accomplish a general visual
inspection for contamination of the surface of the upper arms of the
MLG secondary side brace assemblies, and an eddy current inspection
for cracking of the upper arms by doing all the actions specified in
Parts A and B of the Accomplishment Instructions of Messier-Dowty
Special Inspection Service Bulletin 631-32-178, Revision 1, dated
September 30, 2004. Repeat the eddy current inspection at intervals
not to exceed 800 flight cycles until accomplishment of paragraph
(h) of this AD.
(1) Before the accumulation of 4,000 total flight cycles on the
secondary side brace.
(2) Before the accumulation of 800 flight cycles on the
secondary side brace since overhauled.
(3) Within 200 flight cycles after the effective date of this
AD.
Note 1: For the purposes of this AD, a general visual inspection
is: ``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.''
Related Specified and Corrective Actions
(g) If any cracking is found during any inspection required by
paragraph (f) of this AD: Before further flight, replace the
affected upper arm of the MLG secondary side brace assembly as
specified in paragraph (g)(1) or (g)(2) of this AD.
(1) Replace the aluminum upper arm of the MLG secondary side
brace assembly with a steel upper arm by doing the applicable
actions specified in the Accomplishment Instructions of Messier-
Dowty Service Bulletin 631-32-183, dated October 6, 2004. This
replacement ends the repetitive inspections required by paragraph
(f) of this AD for that side brace only.
(2) Replace the aluminum upper arm of the MLG secondary side
brace assembly with a new or serviceable aluminum upper arm in
accordance with a method approved by either the Manager,
International Branch, ANM-116, Transport Airplane Directorate, FAA;
or the Direction G[eacute]n[eacute]rale de l'Aviation Civile (or its
delegated agent). ATR Component Maintenance Manual, Chapter 32-18-
41, Revision 3, dated September 30, 2002, is one approved method.
Accomplish a general visual inspection for contamination of the
surface of the upper arm before the accumulation of 4,000 total
flight cycles on the upper arm, and if cracks are found, before
further flight, replace the upper arm with a steel upper arm as
required by paragraph (g)(1) of this AD. If no cracks are found,
repeat the eddy current inspection thereafter at intervals not to
exceed 800 flight cycles until accomplishment of paragraph (h) of
this AD.
Terminating Action
(h) Replace all aluminum upper arms of the MLG secondary side
brace assembly with steel upper arms by doing all the applicable
actions in accordance with the Accomplishment Instructions of
Messier-Dowty Service Bulletin 631-32-183, dated October 6, 2004; at
the applicable time specified in paragraph (h)(1), (h)(2), (h)(3),
or (h)(4) of this AD. Accomplishing this replacement ends the
repetitive inspections required by paragraph (f) of this AD.
(1) For airplanes on which any upper arm has been overhauled
before the effective date of this AD and on which Messier-Bugatti
Service Bulletin 631-32-085, dated August 21, 1992, has not been
accomplished, as of the effective date of this AD: Within 15,000
flight cycles or 96 months, whichever is first, since overhaul on
the affected upper arm.
(2) For airplanes on which any upper arm has been overhauled
before the effective date of this AD and on which Messier-Bugatti
Service Bulletin 631-32-085, dated August 21, 1992, has been
accomplished, as of the effective date of this AD: Within 18,000
flight cycles or 96 months, whichever is first, since overhaul on
the affected upper arm.
(3) For airplanes on which any upper arm has not been overhauled
and on which Messier-Bugatti Service Bulletin 631-32-085, dated
August 21, 1992, has not been accomplished, as of the effective date
of this AD: Before the accumulation of 15,000 total flight cycles on
an upper arm since new, or within 96 months on an upper arm since
new, whichever is first.
(4) For airplanes on which any upper arm has not been overhauled
and on which Messier-Bugatti Service Bulletin 631-32-085, dated
August 21, 1992, has been accomplished, as of the effective date of
this AD: Before the accumulation of 18,000 total flight cycles on an
upper arm since new, or within 96 months on an upper arm since new,
whichever is first.
No Report Required
(i) Messier-Dowty Special Inspection Service Bulletin 631-32-
178, Revision 1, dated September 30, 2004, recommends sending an
inspection report to Messier-Dowty, but this AD does not contain
that requirement.
Parts Installation
(j) As of the effective date of this AD, no person may install,
on any airplane, an aluminum upper arm of the MLG secondary side
brace assembly, unless the applicable requirements specified in
paragraphs (f) and (g) of this AD have been accomplished.
Alternative Methods of Compliance (AMOCs)
(k) The Manager, ANM-116, Transport Airplane Directorate, FAA,
has the authority to approve AMOCs for this AD, if requested in
accordance with the procedures found in 14 CFR 39.19.
Related Information
(l) French airworthiness directive F-2004-164, dated October 13,
2004, also addresses the subject of this AD.
Issued in Renton, Washington, on July 14, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-14393 Filed 7-20-05; 8:45 am]
BILLING CODE 4910-13-P