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Proposed Rule

Airworthiness Directives; Aerospatiale Model ATR42-500 and ATR72 Series Airplanes

Document Details

Information about this document as published in the Federal Register.

Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to certain Aerospatiale Model ATR42-500 and ATR72 series airplanes. This proposal would require inspecting the wire bundle in the area of electrical rack 90VU to detect damage, verifying that the conduit around the wire bundle is in the proper position, and installing a clamp between the wire bundles and the carbon shelves structure. This action is necessary to prevent chafing of a wire bundle, which could result in an electrical short and potential loss of several functions essential for safe flight. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by July 18, 2003.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-169-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 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: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2002-NM-169-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 or 2000 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.

Start Further Info

FOR FURTHER INFORMATION CONTACT:

Dan Rodina, Aerospace Engineer; International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2125; fax (425) 227-1149.

End Further Info End Preamble Start Supplemental Information

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 2002-NM-169-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. 2002-NM-169-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 ATR42-500 and ATR72 series airplanes. The DGAC advises that, after parking a Model ATR42-500 series airplane with the right-hand engine on, the flightcrew tried unsuccessfully to start the left-hand engine. Investigation revealed wire chafing on electrical rack 90VU between the carbon structure of the 95VU shelf and the main wire bundle. This chafing led to a short circuit, which burned several wires of the bundle (including the left-hand engine ignition circuits) and the protective sheath (conduit). It was determined that the chafing and subsequent electrical short circuit probably occurred when the wire bundle on the shelf was mispositioned during maintenance, and that this wire bundle is susceptible to such mispositioning. This created a direct contact between the wire bundle and the carbon shelf (an abrasive structure). This condition could also exist on shelves 93VU and 94VU and, if not corrected, could result in the loss of several functions essential for safe flight.

The design of the wire bundle routing is the same on Model ATR42-500 and ATR72 series airplanes; therefore, these airplane models are subject to the identified unsafe condition.

Explanation of Relevant Service Information

The manufacturer has issued Avions de Transport Regional Service Bulletins ATR42-92-0007 (for Model ATR42-500 series airplanes) and ATR72-92-1007 (for Model ATR72 series airplanes), both dated January 25, 2002. These service bulletins describe procedures for inspecting the wire bundles in the area of electrical rack 90VU to detect damage, verifying that the conduit around the wire bundles is in the proper position, and installing a clamp between the wire bundles and the carbon shelves structure (93VU, 94VU, 95VU). Accomplishment of the actions specified in the applicable service bulletins is intended to adequately address the identified unsafe condition. The DGAC classified these service bulletins as mandatory and issued French airworthiness directives 2002-090-092(B) and 2002-091-066(B), both Start Printed Page 36526dated February 20, 2002, 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 §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. The actions would be required to be accomplished in accordance with the service bulletins described previously, except as discussed below.

Difference Between Proposed AD and Service Bulletins

The service bulletins do not provide procedures to repair damaged wiring. This proposed AD would require that damaged wiring be repaired in accordance with the applicable ATR Aircraft Schematic Manual, Chapter 20-27-17, dated October 1, 1995.

Changes to 14 CFR Part 39/Effect on the Proposed AD

On July 10, 2002, the FAA issued a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's airworthiness directives system. The regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance (AMOCs). It is not necessary to include this material in each individual AD; however, the office authorized to approve AMOCs is identified in paragraph (b) of this proposed AD.

Cost Impact

The FAA estimates that 86 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 cost approximately $259 per airplane. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $42,914, or $499 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. 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 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.

Start List of Subjects

List of Subjects in 14 CFR Part 39

End List of Subjects

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:

Start Part

PART 39—AIRWORTHINESS DIRECTIVES

1. The authority citation for part 39 continues to read as follows:

Start Authority

Authority: 49 U.S.C. 106(g), 40113, 44701.

End Authority
[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Aerospatiale: Docket 2002-NM-169-AD.

Applicability: Model ATR42-500 and ATR72 series airplanes, certificated in any category, on which ATR Modification 1447 has been incorporated and ATR Modification 4840 has not been incorporated.

Compliance: Required as indicated, unless accomplished previously.

To prevent chafing of a wire bundle in the area of electrical rack 90VU, which could result in an electrical short and potential loss of several functions essential for safe flight, accomplish the following:

Modification

(a) Within 500 flight hours or 6 months after the effective date of this AD, whichever occurs first: Do a detailed inspection to detect damage of the wire bundles in the area of electrical rack 90VU, ensure that the conduit around the wire bundles is in the proper position, and install a clamp between the wire bundles and the carbon shelves structure (94VU, 94VU, 95VU); in accordance with Avions de Transport Regional Service Bulletin ATR42-92-0007 (for Model ATR42-500 series airplanes) or ATR72-92-1007 (for Model ATR72 series airplanes), both dated January 25, 2002, as applicable. Repair any damaged wiring before further flight in accordance with Chapter 20-27-17 of the applicable ATR Aircraft Schematic Manual, dated October 1, 1995.

Note 1:

For the purposes of this AD, a detailed inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”

Alternative Methods of Compliance

(b) In accordance with 14 CFR 39.19, the Manager, International Branch, ANM-116, FAA, is authorized to approve alternative methods of compliance for this AD.

Note 2:

The subject of this AD is addressed in French airworthiness directives 2002-090-092(B) and 2002-091-066(B), both dated February 20, 2002.

Start Signature

Issued in Renton, Washington, on June 12, 2003.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

End Signature End Part End Supplemental Information

[FR Doc. 03-15338 Filed 6-17-03; 8:45 am]

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