[Federal Register Volume 65, Number 168 (Tuesday, August 29, 2000)]
[Proposed Rules]
[Pages 52369-52371]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-21995]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-26-AD]
RIN 2120-AA64


Airworthiness Directives; Aerospatiale Model ATR42-500 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 Aerospatiale Model ATR42-500 
series airplanes. This proposal would require revising the 
Airworthiness Limitations Section of the Instructions for Continued 
Airworthiness to incorporate life limits for certain items and 
inspections to detect fatigue cracking in certain structures. This 
proposal is prompted by issuance of a new revision of the ``Time 
Limits'' section of the ATR42-400/500 Maintenance Planning Document, 
which specifies new inspections and compliance times for inspection and 
replacement actions. The actions specified by the proposed AD are 
intended to ensure that fatigue cracking of certain structural elements 
is detected and corrected; such fatigue cracking could adversely affect 
the structural integrity of these airplanes.

DATES: Comments must be received by September 28, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-26-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. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2000-NM-26-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 
03, France. This information may be examined at the FAA, Transport 
Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

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.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
     For each issue, state what specific change to the proposed 
AD is being requested.
     Include justification (e.g., reasons or data) for each 
request.
    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 2000-NM-26-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. 2000-NM-26-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

[[Page 52370]]

Discussion

    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for France, has notified the FAA that a new 
revision of the ``Time Limits'' section of ATR42-400/500 Maintenance 
Planning Document (MPD) has been issued. [The FAA refers to the 
information in that section of the MPD as the Airworthiness Limitations 
Section (ALS).] This new revision of the MPD affects Aerospatiale Model 
ATR42-500 series airplanes, which are built to damage-tolerant design 
standards with a design economic repair life of 70,000 flights. The new 
revision is applicable to structural items only, and provides mandatory 
replacement times and structural inspection intervals approved under 
Joint Aviation Requirements/Federal Aviation Regulations (Sec. 25.571 
of the Federal Aviation Regulations (14 CFR 25.571). As airplanes gain 
service experience, or as results of post-certification testing and 
evaluation are obtained, it may become necessary to add additional life 
limits or structural inspections in order to ensure the continued 
structural integrity of the airplane.
    The DGAC advises that analysis of fatigue test data has revealed 
that certain inspections must be performed at specific intervals to 
preclude fatigue cracking in certain areas of the airplane. In 
addition, the DGAC advises that certain life limits must be imposed for 
various components on these airplanes to preclude the onset of fatigue 
cracking in those components. Such fatigue cracking, if not corrected, 
could adversely affect the structural integrity of these airplanes.

Explanation of Relevant Service Information

    Aerospatiale has issued a new ``Time Limits'' section of ATR42-400/
500 MPD, Revision 3, dated February 1999, which includes the following:
    1. Life limit times for certain structural components, or other 
components or equipment.
    2. Structural inspection times to detect fatigue cracking of 
certain Structural Significant Items (SSI's).
    This new revision describes new inspections and compliance times 
for inspection and replacement actions. Accomplishment of those actions 
will preclude the onset of fatigue cracking of certain structural 
elements of the airplane.
    The DGAC has approved the previously referenced MPD in order to 
assure the continued airworthiness of these airplanes in France. The 
DGAC has not issued a corresponding airworthiness directive, although 
accomplishment of the additional life limits and structural inspections 
contained in the MPD may be considered mandatory for operators of these 
airplanes in France.

FAA's Conclusions

    The FAA has reviewed Revision 3 of the previously referenced MPD 
and 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. Pursuant to the bilateral airworthiness 
agreement, the DGAC has kept the FAA informed of the situation 
described above. This airplane model is manufactured in France and is 
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. The FAA 
has determined that Revision 3 of the MPD must be incorporated into the 
ALS of the Instructions for Continued Airworthiness.

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 a revision to the 
ALS of the Instructions for Continued Airworthiness to incorporate 
inspections to detect fatigue cracking of certain SSI's and to revise 
life limits for certain equipment and various components that are 
specified in the previously referenced maintenance document.

Explanation of Action Taken by the FAA

    In accordance with airworthiness standards requiring ``damage 
tolerance assessments'' for transport category airplanes [Sec. 25.1529 
of the Federal Aviation Regulations (14 CFR 25.1529), and the 
Appendices referenced in that section], all products certificated to 
comply with that section must have Instructions for Continued 
Airworthiness (or, for some products, maintenance manuals) that include 
an ALS. That section must set forth:
     Mandatory replacement times for structural components,
     Structural inspection intervals, and
     Related approved structural inspection procedures 
necessary to show compliance with the damage-tolerance requirements.
    Compliance with the terms specified in the ALS is required by 
Secs. 43.16 (for persons maintaining products) and 91.403 (for 
operators) of the Federal Aviation Regulations (14 CFR 43.16 and 
91.403).
    In order to require compliance with these inspection intervals and 
life limits, the FAA must engage in rulemaking, namely the issuance of 
an AD. For products certificated to comply with the referenced part 25 
requirements, it is within the authority of the FAA to issue an AD 
requiring a revision to the ALS that includes reduced life limits, or 
new or different structural inspection requirements. These revisions 
then are mandatory for operators under Sec. 91.403(c) of the Federal 
Aviation Regulations (14 CFR 91.403), which prohibits operation of an 
airplane for which airworthiness limitations have been issued unless 
the inspection intervals specified in those limitations have been 
complied with.
    After that document is revised, as required, and the AD has been 
fully complied with, the life limit or structural inspection change 
remains enforceable as a part of the airworthiness limitations. (This 
is analogous to AD's that require changes to the Limitations Section of 
the Airplane Flight Manual.)
    Requiring a revision of the airworthiness limitations, rather than 
requiring individual inspections, is advantageous for operators because 
it allows them to record AD compliance status only once--at the time 
they make the revision--rather than after every inspection. It also has 
the advantage of keeping all airworthiness limitations, whether imposed 
by original certification or by AD, in one place within the operator's 
maintenance program, thereby reducing the risk of non-compliance 
because of oversight or confusion.

Cost Impact

    The FAA estimates that 8 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 1 work 
hour per airplane to accomplish the proposed actions, 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 
$480, or $60 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no 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.

[[Page 52371]]

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    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:

Aerospatiale: Docket 2000-NM-26-AD.

    Applicability: All Model ATR42-500 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 (c) 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 ensure continued structural integrity of these airplanes, 
accomplish the following:

Airworthiness Limitations Revision

    (a) Within 30 days after the effective date of this AD, revise 
the Airworthiness Limitations Section of the Instructions for 
Continued Airworthiness by incorporating the ``Time Limits'' section 
of the ATR42-400/500 Maintenance Planning Document, Revision 3, 
dated February 1999, into the Airworthiness Limitations Section.
    (b) Except as provided in paragraph (c) of this AD: After the 
actions specified in paragraph (a) of this AD have been 
accomplished, no alternative inspections or inspection intervals may 
be approved for the structural elements specified in the documents 
listed in paragraph (a) of this AD.

Alternative Methods of Compliance

    (c) 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, International Branch, ANM-116, FAA, 
Transport Airplane Directorate. Operators shall submit their 
requests through an appropriate FAA Principal Maintenance Inspector, 
who may add comments and then send it to the Manager, International 
Branch, ANM-116.

    Note 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

Special Flight Permits

    (d) Special flight permits may be issued in accordance with 
Secs. 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.


    Issued in Renton, Washington, on August 23, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-21995 Filed 8-28-00; 8:45 am]
BILLING CODE 4910-13-U