[Federal Register Volume 70, Number 20 (Tuesday, February 1, 2005)]
[Proposed Rules]
[Pages 5081-5083]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-1809]


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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 Series 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 ATR42-200, -300, and -320 series 
airplanes. This proposed AD would require doing repetitive inspections 
of the upper arms of the 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. This proposed 
AD is prompted by an operator who reported experiencing an unlock 
warning for the MLG on the right side of the airplane. We are proposing 
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.

DATES: We must receive comments on this proposed AD by March 3, 2005.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
    <bullet> DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
    <bullet> Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
    <bullet> Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, room PL-401, 
Washington, DC 20590.
    <bullet> By fax: (202) 493-2251.
    <bullet> 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 
Messier-Dowty, BP 10, 78142 Velizy Cedex, 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-2005-20220; the directorate identifier for this 
docket is 2004-NM-152-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-2005-20220; 
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 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 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 ATR42-200, -
300, and -320 series airplanes. The DGAC advises that an operator 
reported experiencing, during taxiing, an unlock warning for the MLG on 
the right side of the airplane. Investigation found that the upper side 
brace of the right MLG was cracked due to accidental damage caused by 
the location of certain identification plates and possible corrosion 
introduced during production. 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.

Relevant Service Information

    Messier-Dowty has issued Special Inspection Service Bulletin 631-
32-175, dated January 7, 2004; and Service Bulletin 631-32-176, 
Revision 1, dated June 2, 2004. Special Inspection Service Bulletin 
631-32-175 describes procedures for doing repetitive general visual 
inspections of the upper arms of the MLG side braces for missing or 
inadequately bonded identification plates having P/Ns D61565-1, D61566-
1, D61567-1, and D61568-1; and replacing any upper arm having a missing 
or inadequately-bonded identification plate with a serviceable upper 
arm having the same part number. Service Bulletin 631-32-176 describes 
procedures for removing the side brace assembly and replacing it with a 
modified part. Modification of the side brace assembly includes the 
following actions:

[[Page 5082]]

    <bullet> Removing and discarding identification plates with P/Ns 
D61565-1, D61566-1, D61567-1, and D61568-1;
    <bullet> Inspecting and restoring the side brace assembly;
    <bullet> Installing identification plates, with P/Ns D61565-1, 
D61566-1, D61567-1, and D61568-1, in a new location; and
    <bullet> Reidentifying the modified side brace 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-
2004-006, dated January 7, 2004, to ensure the continued airworthiness 
of these airplanes in France.

FAA's Determination and Requirements of the Proposed AD

    These airplane models are manufactured in France and are type 
certificated for operation in the United States under the provisions of 
Sec.  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 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 the service information 
described previously, except as discussed under ``Difference Between 
the Proposed AD and French Airworthiness Directive.''

Difference Between the Proposed AD and French Airworthiness Directive

    Operators should note that, although the French airworthiness 
directive recommends accomplishing the replacement of the side brace 
assemblies at the next overhaul, we have determined that a specific 
compliance time is needed to ensure that the identified unsafe 
condition is addressed in a timely manner. In developing an appropriate 
compliance time for this proposed AD, we considered not only the 
manufacturer's recommendation, but also the degree of urgency 
associated with addressing the subject unsafe condition, and the 
average utilization of the affected fleet. Considering these factors, 
this proposed AD requires replacement before the accumulation of 15,000 
total flight cycles on a side brace assembly or 96 months on a side 
brace assembly since new, whichever occurs first. We find that this 
compliance time is warranted, in that it represents an appropriate 
interval of time allowable for affected airplanes to continue to 
operate without compromising safety.

Costs of Compliance

    The following table provides the estimated costs for U.S. operators 
to comply with this proposed AD.

                                                                     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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Inspection, per inspection cycle.....               1             $65  None....................             $65               7  $455, per inspection
                                                                                                                                  cycle.
Replacement of side brace assemblies.               2              65  0.......................             130               7  $910.
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Authority for This Rulemaking

    The FAA's authority to issue rules regarding aviation safety is 
found in Title 49 of the United States Code. 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.
    This rulemaking is promulgated 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 
proposed AD.

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:

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-2005-20220; Directorate Identifier 
2004-NM-152-AD.

Comments Due Date

    (a) The Federal Aviation Administration must receive comments on 
this AD action by March 3, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Aerospatiale Model ATR42-200, -300, and -
320 series airplanes

[[Page 5083]]

with main landing gear (MLG) side brace assemblies, part number (P/
N) D22710000-7, equipped with upper arms having P/N D56778-10, 
serial numbers MN 566 through MN 581 inclusive; certificated in any 
category.

Unsafe Condition

    (d) This AD was prompted by 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 repetitive inspections and replacements specified in 
paragraphs (g) and (h) of this AD, respectively: Messier-Dowty 
Special Inspection Service Bulletin 631-32-175, dated January 7, 
2004; and
    (2) For the replacements specified in paragraph (i) 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 occurs first: Do a general visual inspection 
of the upper arms of the MLG side braces for missing or inadequately 
bonded identification plates having P/Ns D61565-1, D61566-1, D61567-
1, and D61568-1, in accordance with the service bulletin. Thereafter 
at intervals not to exceed 2 months or 500 flight hours, whichever 
occurs first: Repeat the inspection of the upper arm of the MLG side 
brace for any side brace assembly that has not been replaced as 
required by paragraph (i) 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.''

Replacement of Upper Arms, If Necessary

    (h) If any identification plate, P/N D61565-1, D61566-1, D61567-
1, or D61568-1, is found missing or inadequately bonded during any 
inspection required by paragraph (g) of this AD: Within 25 flight 
hours since the most recent inspection, replace any upper arm having 
a missing or inadequately bonded identification plate with a 
serviceable upper arm having the same part number, in accordance 
with the service bulletin.

Replacement With Modified Side Brace Assemblies

    (i) Before the accumulation of 15,000 total flight cycles on a 
side brace assembly or 96 months on a side brace assembly since new, 
whichever occurs first: 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 both side 
brace assemblies of the MLG are replaced with modified parts, no 
more work is required by paragraph (g) of this AD.

Credit for Previous Service Bulletin

    (j) Replacements done before the effective date of this AD in 
accordance with Messier-Dowty Service Bulletin 631-32-176, dated 
February 26, 2004, is acceptable for compliance with the 
corresponding requirements of paragraph (i) of this AD.

Alternative Methods of Compliance (AMOCs)

    (k) 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.

Related Information

    (l) French airworthiness directive F-2004-006, dated January 7, 
2004, also addresses the subject of this AD.

    Issued in Renton, Washington, on January 21, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-1809 Filed 1-31-05; 8:45 am]
BILLING CODE 4910-13-P