[Federal Register Volume 66, Number 81 (Thursday, April 26, 2001)]
[Proposed Rules]
[Pages 20946-20948]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-10346]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-38-AD]
RIN 2120-AA64


Airworthiness Directives; Aerospatiale Model ATR72-101, -201, -
102, -202, -211, and -212 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 certain Aerospatiale Model ATR72-
101, -201, -102, -202, -211, and -212 series airplanes. This proposal 
would require replacement of the clamp retaining the power supply cable 
loom of the green circuit hydraulic pump at frame 28 with a smaller 
clamp in a different orientation. This action is necessary to prevent 
the chafing of electrical wires, which could cause a short circuit and 
failure of the elevator control cable and the green system hydraulic 
pump, resulting in reduced controllability of the airplane and 
consequent injury to the crew and passengers. This action is intended 
to address the identified unsafe condition.

DATES: Comments must be received by May 29, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-38-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00

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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. 2001-
NM-38-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: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1175; 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 action 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 action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2001-NM-38-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. 2001-NM-38-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for, notified the FAA that an unsafe condition 
may exist on certain Aerospatiale Model ATR72-101, -201, -102, -202, -
211, and -212 series airplanes. The DGAC advises that Model ATR72-202 
series airplane, while taxiing out, experienced an elevator pitch 
disconnect; a loss of the green system hydraulic pump; and eruption of 
a small fire. Investigations revealed that the power supply cables of 
the green system hydraulic pump had chafed on the right-hand elevator 
control cable, between frames 28 and 28A. This chafing led to a short 
circuit, which caused the elevator control cable to snap and the 
hydraulic pump power supply circuit breaker to trip. The heat generated 
started a small fire, which extinguished itself.
    It was determined that the chafing and subsequent electrical short 
circuit were caused by the installation of an oversized clamp (diameter 
20 mm) on the power supply cables loom (diameter 16 mm) of the green 
system hydraulic pump. The larger clamp gave the cables freedom to move 
and did not secure wiring conduit 2P in the forward area, where the 
cables loom changes direction. This condition, if not corrected, could 
cause the chafing of electrical wires, and consequent short circuit, 
snapping of the elevator control cable, tripping of the hydraulic pump 
power supply circuit breaker, and possible fire, resulting in reduced 
controllability of the airplane and consequent injury to the crew and 
passengers.

Explanation of Relevant Service Information

    Aerospatiale has issued Avions de Transport Regional Service 
Bulletin ATR72-92-1004, dated January 26, 2001, which describes 
procedures for a one-time inspection of harness route 2P and the pitch 
control cable for wire chafing, corrective action, if necessary, and 
replacement of the 20 mm clamp with a 16 mm clamp in a rotated 
position. Accomplishment of the actions specified in the service 
bulletin is intended to adequately address the identified unsafe 
condition. The DGAC classified this service bulletin as mandatory and 
issued French airworthiness directive 2001-056-055(B), dated February 
7, 2001, in order to assure the continued airworthiness of these 
airplanes in France.

FAA's Conclusions

    These airplane models are manufactured in France and are 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. The FAA has examined the findings of 
the DGAC, reviewed 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.

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 accomplishment of 
the actions specified in the service bulletin described previously.

Cost Impact

    The FAA estimates that 60 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 replacement, and that the 
average labor rate is $60 per work hour. Required parts would be 
supplied by the manufacturer at no cost to the operators. Based on 
these figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $3,600, 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 proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific

[[Page 20948]]

actions actually required by the AD. These figures typically do not 
include incidental costs, such as the time required to gain access and 
close up, planning time, or time necessitated by other administrative 
actions.

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 2001-NM-38-AD.

    Applicability: Model ATR72-101, -201, -102, -202, -211, and -212 
series airplanes, certificated in any category, except those on 
which Modification 3719 has been performed.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 prevent the chafing of electrical wires, which could cause a 
short circuit and failure of the elevator control cable and the 
green system hydraulic pump, resulting in reduced controllability of 
the airplane and consequent injury to the crew and passengers, 
accomplish the following:

Inspection and Corrective Action

    (a) Within 25 days after the effective date of this AD: Perform 
a general visual inspection of harness route 2P and the pitch 
control cable for chafing, in accordance with Avions de Transport 
Regional Service Bulletin ATR72-92-1004, dated January 26, 2001.
    (1) If no chafing is found, no further action is required by 
this paragraph.
    (2) If any chafing of the harness route 2P or the pitch control 
cable is found during the inspection, prior to further flight, 
replace the applicable part with a new or serviceable part in 
accordance with Avions de Transport Regional Service Bulletin ATR72-
92-1004, dated January 26, 2001.


    Note 2: For the purposes of this AD, a general visual inspection 
is defined as: ``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 under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light, 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.''


    (b) Within 25 days after the effective date of this AD: Remove 
the oversized clamp (20 mm), part number (P/N) NSA935807-20, at 
frame 28, which retains power supply cables loom 2P for the green 
circuit hydraulic pump, and install a 16mm clamp, P/N NSA935807-16, 
with new orientation, in accordance with Avions de Transport 
Regional Service Bulletin ATR72-92-1004, dated January 26, 2001.

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, 
Transport Airplane Directorate, FAA. 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 3: 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 
sections 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.


    Note 4: The subject of this AD is addressed in French 
airworthiness directive 2001-056-055(B), dated February 7, 2001.


    Issued in Renton, Washington, on April 19, 2001.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-10346 Filed 4-25-01; 8:45 am]
BILLING CODE 4910-13-U