[Federal Register: December 13, 2005 (Volume 70, Number 238)]
[Proposed Rules]
[Page 73671-73674]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr13de05-25]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2005-20220; Directorate Identifier 2004-NM-152-AD]
RIN 2120-AA64
Airworthiness Directives; Aerospatiale Model ATR42-200, -300, and
-320 Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).
ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of
comment period.
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SUMMARY: The FAA is revising an earlier NPRM for an airworthiness
directive (AD) that applies to certain Aerospatiale Model ATR42-200, -
300, and -320 airplanes. The original NPRM would have required doing
repetitive inspections of the upper arms of the main landing gear (MLG)
side braces for missing or inadequately bonded identification plates;
replacing the upper arm if necessary; and replacing the side brace
assembly with a modified part. The original NPRM resulted from an
operator who reported experiencing an unlock warning for the MLG on the
right side of the airplane. This action revises the original NPRM by
proposing to require doing an ultrasonic inspection of the upper arm of
the MLG side brace for any defects and related investigative/corrective
actions if necessary, instead of replacing the upper arm if necessary.
This action also adds airplanes to the applicability. We are proposing
this supplemental NPRM to prevent cracking of the upper arms of the
side braces of the MLG, which could result in failure of the MLG during
landing and possible damage to the airplane and injury to the
flightcrew and passengers.
DATES: We must receive comments on this supplemental NPRM by January 9,
2006.
ADDRESSES: Use one of the following addresses to submit comments on
this supplemental NPRM.
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.
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.
Contact Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex
03, France, for service information identified in this proposed AD.
FOR FURTHER INFORMATION CONTACT: Tom Rodriguez, Aerospace Engineer,
International Branch, ANM-116, Transport Airplane Directorate, FAA,
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 supplemental NPRM. Include the docket number
``Docket No. FAA-2005-20220; Directorate Identifier 2004-NM-152-AD'' at
the beginning of your comments. We specifically invite comments on the
overall regulatory, economic, environmental, and energy aspects of this
supplemental NPRM. We will consider all comments received by the
closing date and may amend this supplemental NPRM in light of those
comments.
We will post all comments submitted, 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 supplemental NPRM. Using the search function
of that 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 may review the DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
may visit http://dms.dot.gov.
Examining the Docket
You may 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 in the Nassif Building at the DOT
street address stated in ADDRESSES. Comments will be available in the
AD docket shortly after the Docket Management System receives them.
Discussion
We proposed to amend 14 CFR part 39 with a notice of proposed
rulemaking (NPRM) for an airworthiness directive (AD) (the ``original
NPRM''). The original NPRM applies to certain Aerospatiale Model ATR42-
200, -300, and -320 airplanes. The original NPRM was published in the
Federal Register on February 1, 2005 (70 FR 5081). The original NPRM
proposed to require doing repetitive inspections of the upper arms of
the main landing gear (MLG) side braces for missing or inadequately
bonded identification plates; replacing the upper arm if necessary; and
replacing the side brace assembly with a modified part.
Relevant Service Information
Since the original NPRM was issued, Messier-Dowty has issued
Special Inspection Service Bulletin 631-32-181, Revision 2, dated June
3, 2005. (Messier-Dowty Special Inspection Service Bulletin 631-32-175,
dated January 7, 2004, was referenced in the original NPRM as the
appropriate source of service information for doing the repetitive
inspections and replacements of the upper arms if necessary.) Revision
2 of the service bulletin describes procedures for doing repetitive
visual inspections of the upper arms of the MLG side brace assemblies
for missing or partially unstuck identification plates and beads of
glue. If any identification plate or bead of glue is missing or
partially unstuck, the service bulletin also describes procedures for
doing an ultrasonic inspection of the upper arm of the MLG side brace
for any defects and doing related investigative and corrective actions
if necessary. The related investigative action is a visual inspection
of the MLG side brace surface for any paint tears, scratches, or
corrosion prior to accomplishing the ultrasonic inspection. The
corrective actions include the following:
[[Page 73672]]
If any paint tear, scratch, or corrosion is found on the
surface of the upper arm, removing the contamination prior to doing the
ultrasonic inspection.
If the echo is less than 20%, restoring the plate areas
and reidentifying the identification plate.
If the echo is 20% or greater, replacing the MLG side
brace with an MLG side brace equipped with an airworthy upper arm.
Accomplishing the actions specified in Messier-Dowty Special
Inspection Service Bulletin 631-32-181, Revision 2, and the
replacements in Messier-Dowty Service Bulletin 631-32-176, Revision 1,
dated June 2, 2004, is intended to adequately address the unsafe
condition. (Messier-Dowty Service Bulletin 631-32-176, Revision 1, was
referenced in the original NPRM as the appropriate source of service
information for replacing a side brace assembly with a modified part.)
The Direction Generale de l'Aviation Civile (DGAC), which is the
airworthiness authority for France, mandated the service information
and issued French airworthiness directive F-2005-106, dated July 6,
2005, to ensure the continued airworthiness of these airplanes in
France. French airworthiness directive F-2005-106 supersedes French
airworthiness directive F-2004-006, dated January 7, 2004, which was
referenced as related information in paragraph (l) of the original
NPRM. French airworthiness directive F-2005-106 also adds new airplanes
to the applicability. We have revised the applicability of the
supplemental NPRM to match French airworthiness directive F-2005-106.
Clarification Between the Supplemental NPRM and Service Bulletin
Where Messier-Dowty Special Inspection Service Bulletin 631-32-181,
Revision 2, specifies replacing a side brace with a side brace equipped
with an airworthy upper arm, this supplemental NPRM proposes to replace
it with a side brace equipped with an upper arm modified in accordance
with Messier-Dowty Service Bulletin 631-32-176, Revision 1.
Clarification of Inspection Terminology
The ``visual inspection'' specified in Revision 2 of Messier-Dowty
Special Inspection Service Bulletin 631-32-181 is referred to as a
``general visual inspection'' in this supplemental NPRM. We have
included the definition for a general visual inspection in a note in
the supplemental NPRM.
Clarification of Alternative Method of Compliance (AMOC) Paragraph
We have revised this supplemental NPRM to clarify the appropriate
procedure for notifying the principal inspector before using any
approved AMOC on any airplane to which the AMOC applies.
Comments
We have considered the following comments on the original NPRM.
Request to Use AMOC
One commenter requests that we revise the original NPRM to allow
operators a means for mitigating any corrosion and reidentifying the
upper arms of the MLG side braces, rather than proposing to require
replacement of the upper arms. The commenter suggests that a
combination of blending, coating, and a part identification method such
as electro-etching would be a more appropriate solution to address the
unsafe condition of the original NPRM. The commenter states that
electro-etching would have minimal structural impact on the upper arms,
while providing a permanent mark that can only be removed by grinding.
We partially agree. As stated previously, if any identification
plate or bead of glue is missing or partially unstuck, this
supplemental NPRM proposes to require doing an ultrasonic inspection of
the upper arm of an MLG side brace for any defects (and doing related
investigative and corrective actions if necessary), rather than
proposing to replace the upper arm. Although, depending on the results
of the ultrasonic inspection, operators may be required to replace the
side brace assembly with a part modified in accordance with Messier-
Dowty Service Bulletin 631-32-176, Revision 1. This supplemental NPRM
also proposes to require modification of the side brace assemblies to
terminate the repetitive visual inspections. However, under the
provisions of paragraph (m) of the proposed final rule, we may consider
requests for approval of an AMOC if sufficient data are submitted to
substantiate that such a design change would provide an acceptable
level of safety.
Request to Withdraw NPRM
The same commenter believes that the original NPRM is an
overreaction to a single event, the cause of which can still be
speculated upon. The commenter also believes that any potential unsafe
condition can be addressed by other means. We infer the commenter
requests that we withdraw the original NPRM.
We do not agree. Although the original NPRM was prompted by one
report, we have identified an unsafe condition that is likely to exist
or develop on other products of the same type design. The affected
identification plates are located in a high stress area where they
could be torn down. When an identification plate is torn down, the
protective treatment on the upper arm of the MLG side brace could be
damaged or stripped. Damaged or stripped protective treatment could
lead to corrosion and consequent cracking of the upper arms of the MLG
side braces. We have also considered the action taken by the authority
of the state of design and the manufacturer's recommendation. Cracking
of the upper arms of the side braces of the MLG, if not corrected,
could result in failure of the MLG during landing and possible damage
to the airplane and injury to the flightcrew and passengers.
FAA's Determination and Proposed Requirements of the Supplemental NPRM
The changes discussed above expand the scope of the original NPRM;
therefore, we have determined that it is necessary to reopen the
comment period to provide additional opportunity for public comment on
this supplemental NPRM.
Costs of Compliance
The following table provides the estimated costs for U.S. operators
to comply with this supplemental NPRM.
Estimated Costs
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Number of U.S.-
Action Work hours Average labor Parts Cost per registered Fleet cost
rate per hour airplane airplanes
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General visual inspection, per 1....................... $65 None $65 54 $3,510, per inspection
inspection cycle. cycle.
[[Page 73673]]
Replacement of side brace assemblies. 2 (1 hour per side 65 $0 130 54 7,020
brace).
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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 supplemental NPRM 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, 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 Federal Aviation Administration (FAA) amends Sec. 39.13 by
adding the following new airworthiness directive (AD):
Aerospatiale: Docket No. FAA-2005-20220; Directorate Identifier
2004-NM-152-AD.
Comments Due Date
(a) The FAA must receive comments on this AD action by January
9, 2006.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Aerospatiale Model ATR42-200, -300, and -
320 airplanes, certificated in any category; with main landing gear
(MLG) side brace assemblies having part number (P/N) D22710000-( )
except -8, equipped with upper arms having P/N D56778-10.
Unsafe Condition
(d) This AD results from an operator who reported experiencing
an unlock warning for the MLG on the right side of the airplane. We
are issuing this AD to prevent cracking of the upper arms of the
side braces of the MLG, which could result in failure of the MLG
during landing and possible damage to the airplane and 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.
Service Bulletin References
(f) The term ``service bulletin,'' as used in this AD, means the
Accomplishment Instructions of the following service bulletins, as
applicable:
(1) For the general visual inspection and ultrasonic inspection
specified in paragraphs (g) and (h) of this AD, respectively:
Messier-Dowty Special Inspection Service Bulletin 631-32-181,
Revision 2, dated June 3, 2005; and
(2) For the replacement specified in paragraph (j) of this AD:
Messier-Dowty Service Bulletin 631-32-176, Revision 1, dated June 2,
2004.
Repetitive Inspections of Identification Plates
(g) Within 2 months or 500 flight hours after the effective date
of this AD, whichever is first: Do a general visual inspection of
the upper arms of the MLG side braces for inadequately bonded
identification plates having P/Ns D61565-1, D61566-1, D61567-1, and
D61568-1 and for any missing bead of glue, in accordance with the
service bulletin. Thereafter at intervals not to exceed 2 months or
500 flight hours, whichever is first: Repeat the inspection of the
upper arm of the MLG side brace for any side brace assembly that has
not been inspected in accordance with paragraph (h) of this AD or
replaced as required by paragraph (j) 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
ensure visual access to all 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.''
Ultrasonic Inspection, if Necessary
(h) If any identification plate having P/N D61565-1, D61566-1,
D61567-1, or D61568-1 or any bead of glue is missing or found
inadequately bonded during any inspection required by paragraph (g)
of this AD: Within 25 flight hours since the most recent general
visual inspection, do an ultrasonic inspection of the upper arm of
the MLG side brace for any defects and do any related investigative
and corrective actions as applicable, by doing all of the applicable
actions specified in Part B.(3) of the service bulletin; except
where the service bulletin specifies replacing the side brace with a
side brace equipped with an airworthy upper arm, replace it with a
part modified in accordance with paragraph (j) of this AD. Any
corrective actions must be done before further flight after doing
the ultrasonic inspection.
[[Page 73674]]
Additional Ultrasonic Inspection for Certain Airplanes
(i) For airplanes on which the ultrasonic inspection specified
in paragraph (h) of this AD has been accomplished in accordance with
Messier-Dowty Special Inspection Service Bulletin 631-32-181,
Revision 1, dated March 16, 2005: Within 25 flight hours after the
effective date of the AD, do all the applicable actions specified in
paragraph (h) of this AD, in accordance with Messier-Dowty Special
Inspection Service Bulletin 631-32-181, Revision 2, dated June 3,
2005.
Replacement with a Modified Side Brace Assembly
(j) At the applicable compliance time specified in paragraphs
(j)(1) or (j)(2) of this AD: Remove the side brace assembly and
replace it with a part modified by doing all of the actions in the
service bulletin. Replacement of a side brace assembly with a
modified part terminates the repetitive inspections required by
paragraph (g) of this AD for that modified side brace assembly only.
If the side brace assembly of the left and right MLG is replaced
with a modified part, no more work is required by paragraph (g) of
this AD.
(1) For airplanes on which Messier-Dowty Service Bulletin 631-
32-072 has not been accomplished: Before the accumulation of 15,000
total flight cycles on a side brace assembly since new or since last
overhaul, or 96 months on a side brace assembly since new or since
last overhaul, whichever is first.
(2) For airplanes on which Messier-Dowty Service Bulletin 631-
32-072 has been accomplished: Before the accumulation of 18,000
total flight cycles on a side brace assembly since new or since last
overhaul, or 96 months on a side brace assembly since new or since
last overhaul, whichever is first.
Credit for Previous Service Bulletin
(k) Replacements done before the effective date of this AD in
accordance with Messier-Dowty Service Bulletin 631-32-176, dated
February 26, 2004, are acceptable for compliance with the
corresponding requirements of paragraph (j) of this AD.
No Reporting Requirement
(l) Although Messier-Dowty Special Inspection Service Bulletin
631-32-181, Revision 2, dated June 3, 2005, specifies to submit
certain information to the manufacturer, this AD does not include
that requirement.
Alternative Methods of Compliance (AMOCs)
(m)(1) The Manager, International Branch, 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.
(2) Before using any AMOC approved in accordance with 14 CFR
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
(n) French airworthiness directive F-2005-106, dated July 6,
2005, also addresses the subject of this AD.
Issued in Renton, Washington, on December 6, 2005.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 05-23953 Filed 12-12-05; 8:45 am]
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