[Federal Register Volume 66, Number 80 (Wednesday, April 25, 2001)]
[Proposed Rules]
[Pages 20768-20770]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 01-10178]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-08-AD]
RIN 2120-AA64


Airworthiness Directives; Aerospatiale Model ATR42-200, -300, and 
-320 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 ATR42-
200, -300, and -320 series airplanes. This proposal would require 
modifying the wiring of the starting rotary switch. This action is 
necessary to prevent the loss of electrical power supply of the DC 
emergency and standby buses, which could result in the loss of some 
electrical loads and the consequent display of erroneous information to 
the flight crew. This action is intended to address the identified 
unsafe condition.

DATES: Comments must be received by May 25, 2001.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-08-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. 2001-NM-08-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,

[[Page 20769]]

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) 
227-2110; 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 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 2001-NM-08-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 2001-NM-08-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-
4056.

Discussion

    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for France, notified the FAA that an unsafe 
condition may exist on certain Aerospatiale Model ATR42-200, -300, and 
-320 series airplanes. The DGAC advises that the flightcrew of a Model 
ATR42-320 series airplane switched off the emergency battery following 
a charge fault, and subsequently experienced a partial loss of direct 
current (DC) power during descent when they selected the continuous 
relight position on the starting rotary switch. This type of failure 
could occur on an airplane if the continuous relight position of the 
engine start selector is not wired to the ground. In this case, the DC 
power of the emergency and standby buses is transferred from DC bus 1 
(the main network) to the failed emergency battery, resulting in the 
loss of some electrical loads. This condition, if not corrected, could 
result in the display of erroneous information to the flightcrew.

Similar Models

    The continuous relight position of the engine start selector is 
similar on ATR42-200, -300, and -320 series airplanes; therefore, these 
airplanes are all subject to the identified unsafe condition.

Explanation of Relevant Service Information

    The manufacturer has issued Avions de Transport Regional Service 
Bulletin ATR42-80-0001, Revision 2, dated November 15, 2000. The 
service bulletin describes procedures for modifying the starting rotary 
switch by installing wiring connecting the ground to the continuous 
relight 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 2000-454-081(B), 
dated November 15, 2000, to ensure 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 4 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Required parts would be 
provided by the manufacturer at no cost to operators. Based on these 
figures, the cost impact of the proposed AD on U.S. operators is 
estimated to be $14,400, or $240 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 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

[[Page 20770]]

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-08-AD.

    Applicability: Model ATR42-200, -300, and -320 series airplanes, 
certificated in any category; except those modified in accordance 
with Modification 3047 or Avions de Transport Regional Service 
Bulletin ATR42-80-0001.

    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 (b) 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 loss of electrical power supply of the DC 
emergency and standby buses, which could result in the loss of some 
electrical loads and the consequent display of erroneous information 
to the flight crew, accomplish the following:

Modification

    (a) Within 6 months after the effective date of this AD, modify 
the wiring of the starting rotary switch, in accordance with Avions 
de Transport Regional Service Bulletin ATR42-80-0001, Revision 2, 
dated November 15, 2000.

Alternative Methods of Compliance

    (b) 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 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

    (c) 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 3: The subject of this AD is addressed in French 
airworthiness directive 2000-454-081(B), dated November 15, 2000.


    Issued in Renton, Washington, on April 18, 2001.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 01-10178 Filed 4-24-01; 8:45 am]
BILLING CODE 4910-13-P