[Federal Register Volume 63, Number 54 (Friday, March 20, 1998)]
[Proposed Rules]
[Pages 13574-13575]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-7222]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-24-AD]
RIN 2120-AA64


Airworthiness Directives; Aerospatiale Model ATR42-300 and -320, 
and Model ATR72 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-
300 and -320, and Model ATR72 series airplanes. This proposal would 
require modification of the engine fuel drainage system. This proposal 
is prompted by issuance of mandatory continuing airworthiness 
information by a foreign civil airworthiness authority. The actions 
specified by the proposed AD are intended to prevent fuel from 
overflowing into the engine nacelle, which could result in a fire in 
the nacelle.

DATES: Comments must be received by April 20, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-24-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.
    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.
    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 98-NM-24-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. 98-NM-24-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 ATR42-300 and -320, 
and Model ATR72 series airplanes. The DGAC advises that the existing 
design of the engine fuel drainage system could allow the drainage 
system to clog. If the engine fuel drainage system is clogged, fuel 
leakage from the nozzles or turbine may result in fuel overflowing into 
the engine nacelle. This condition, if not corrected, could result in a 
fire in the nacelle.

Explanation of Relevant Service Information

    Aerospatiale has issued Service Bulletin ATR42-71-0010, Revision 4, 
dated October 23, 1996 (for Model ATR42 series airplanes), which 
describes procedures for modifying the engine fuel drainage system to 
allow improved drainage. This modification involves bypassing the 
manifold by disconnecting the drain pipe from the engine nozzle to the 
manifold, installing a plug on the manifold where the drain pipe was 
connected, and connecting a new drain hose from the engine nozzle drain 
point directly to the breather tube outlet.
    Aerospatiale also has issued Service Bulletin ATR72-71-1006, 
Revision 1, dated October 21, 1996 (for Model ATR72 series airplanes), 
which describes procedures for modifying the engine fuel drainage 
system. This modification involves isolating the engine turbine drain 
pipe from the collector manifold by installing a new

[[Page 13575]]

drain pipe, which bypasses the manifold.
    Accomplishment of the actions specified in the service bulletins is 
intended to adequately address the identified unsafe condition. The 
DGAC classified these service bulletins as mandatory and issued French 
airworthiness directives 96-109-063 (B) and 96-110-030 (B), both dated 
June 5, 1996, 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 bulletins described previously.

Cost Impact

    The FAA estimates that 145 airplanes of U.S. registry would be 
affected by this proposed AD.
    For Model ATR42-300 and -320 series airplanes (106 airplanes), it 
would take approximately 8 work hours per airplane to accomplish the 
proposed modification, at an average labor rate of $60 per work hour. 
Required parts would be provided by the manufacturer at no cost to the 
operators. Based on these figures, the cost impact of this modification 
proposed by this AD on U.S. operators is estimated to be $50,880, or 
$480 per airplane.
    For Model ATR72 series airplanes (39 airplanes), it would take 
approximately 15 work hours per airplane to accomplish the proposed 
modification, at an average labor rate of $60 per work hour. Required 
parts would cost approximately $1,499 per airplane. Based on these 
figures, the cost impact of this modification proposed by this AD on 
U.S. operators is estimated to be $93,561, or $2,399 per airplane.
    The cost impact figures discussed above are 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.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects 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, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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 98-NM-24-AD.

    Applicability: Model ATR42-300 and -320 series airplanes, on 
which Aerospatiale Modification 1696 (reference Aerospatiale Service 
Bulletin ATR42-71-0010) has not been accomplished; and Model ATR72-
101, -201, -102, -202, -211, and -212 series airplanes, on which 
Aerospatiale Modification 3742 (reference Aerospatiale Service 
Bulletin ATR72-71-1006) has not been accomplished; certificated in 
any category.

    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 fuel from overflowing into the engine nacelle, which 
could result in a fire in the nacelle, accomplish the following:
    (a) Within 24 months after the effective date of this AD, modify 
the engine fuel drainage system, in accordance with Aerospatiale 
Service Bulletin ATR42-71-0010, Revision 4, dated October 23, 1996 
(for Model ATR42 series airplanes), or Aerospatiale Service Bulletin 
ATR72-71-1006, Revision 1, dated October 21, 1996 (for Model ATR72 
series airplanes), as applicable.
    (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, 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.

    (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 directives 96-109-063 (B) and 96-110-030 (B), both 
dated June 5, 1996.

    Issued in Renton, Washington, on March 13, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-7222 Filed 3-19-98; 8:45 am]
BILLING CODE 4910-13-P