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Proposed Rule

Airworthiness Directives; Aerospatiale Model ATR42 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 and ATR72 series airplanes. This proposal would require replacement of the swinging lever spacers in the left and right leg assemblies of the main landing gear with new, improved spacers. This action is necessary to prevent propagation of fatigue cracking, which could result in failure of the spacer base and could affect the symmetrical functioning of the braking system. Asymmetrical braking could result in the airplane overrunning the runway during takeoff or landing. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by January 16, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Start Printed Page 70209Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-116-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-116-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.

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FOR FURTHER INFORMATION CONTACT:

Tony Jopling, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2190; 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-116-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-116-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 and ATR72 series airplanes. The DGAC advises that several cases of fatigue cracking have been found on the swinging lever spacers in the main landing gear (MLG). The fatigue cracking is located at the intersection base of the spacer, and is due to a stress concentration. Propagation of such cracking could result in failure of the spacer base and could affect the symmetrical functioning of the braking system. Asymmetrical braking could result in the airplane overrunning the runway during takeoff or landing.

Explanation of Relevant Service Information

The manufacturer has issued Avions de Transport Regional Service Bulletins ATR42-32-0094 and ATR72-32-1042, both dated November 26, 2001. The Avions de Transport Regional Service Bulletins reference Messier-Dowty Service Bulletins 631-32-166, dated November 28, 2001 (for Model ATR42 series airplanes); and 631-32-165, dated November 27, 2001 (for Model ATR72 series airplanes) for accomplishment of the replacement of the swinging lever spacers of the MLG. The Messier-Dowty service bulletins describe procedures for replacement of the swinging lever spacers in the left and right leg assemblies of the MLG with new, improved spacers. The new spacers were manufactured using 7175 material, which is stronger than the 2024 and 7010 material used in the existing spacers. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition. The DGAC classified the Avions de Transport Regional service bulletins as mandatory and issued French airworthiness directives 2001-614-089(B) and 2001-615-062(B), both dated December 26, 2001, 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 us informed of the situation described above. We have 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 AD

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 information described previously, except as discussed below.

Differences Among French Airworthiness Directive, Service Information, and Proposed AD

The applicability specified in French airworthiness directive 2001-614-089(B) includes Aerospatiale Model ATR42-400; however, this proposed AD does not include that model because no U.S. type certificate has been issued for that airplane.

Paragraph 1.C.(4) of service bulletin ATR42-32-0094 references Messier-Dowty Service Bulletin No. 631-32-165 for the replacement of the swinging lever spacers of the MLG; however, the correct number for that service bulletin is No. 631-32-166. The manufacturer has been notified of this typographical error and will be issuing a revised service bulletin.

Cost Impact

The FAA estimates that 133 airplanes of U.S. registry would be affected by this proposed AD, that it would take about Start Printed Page 7021016 work hours per airplane to accomplish the proposed replacement, and that the average labor rate is $65 per work hour. Required parts would cost between $921 and $4,272 per airplane. Based on these figures, the cost impact of the proposed replacement on U.S. operators is estimated to be between $1,961 and $5,312 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 levers 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.

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List of Subjects in 14 CFR Part 39

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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:

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PART 39—AIRWORTHINESS DIRECTIVES

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

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

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[Amended]

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

Aerospatiale: Docket 2002-NM-116-AD.

Applicability: Model ATR42-200, -300, -320, and -500 series airplanes on which ATR Modification 5338 has not been done; and Model ATR72-101, -102, -201, -202, -211, -212, and -212A series airplanes on which ATR Modification 5337 has not been done; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the spacer base of the swinging lever spacers in the left and right leg assemblies of the main landing gear (MLG) and consequent asymmetrical braking, which could result in the airplane overrunning the runway during takeoff or landing, accomplish the following:

Replacement

(a) Replace the swinging lever spacers in the left and right leg assemblies of the MLG with new, improved spacers, per Avions de Transport Regional Service Bulletins ATR42-32-0094 and ATR72-32-1042, both dated November 26, 2001. Do the replacement at the applicable time specified in paragraphs (a)(1) or (a)(2) of this AD.

(1) For Model ATR42-200, -300, and -320, and Model ATR72-101, -102, -201, -202, -211, -212, and -212A series airplanes: Do the replacement at the later of the times specified in paragraphs (a)(1)(i) and (a)(1)(ii) of this AD.

(i) Before the accumulation of 15,000 total landings or 8 years in-service on new or overhauled swinging lever spacers, whichever is first.

(ii) Within 3,000 landings after the effective date of this AD.

(2) For Model ATR42-500 series airplanes: Do the replacement before the accumulation of 18,000 total landings or 9 years in-service on new or overhauled swinging lever spacers, whichever is first.

(b) Messier-Dowty Service Bulletins 631-32-166, dated November 28, 2001 (for Model ATR42 series airplanes); and 631-32-165, dated November 27, 2001 (for Model ATR72 series airplanes), may be used for accomplishment of the replacement required by paragraph (a) of this AD.

Alternative Methods of Compliance

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

Note 1:

The subject of this AD is addressed in French airworthiness directives 2001-614-089(B) and 2001-615-062(B), both dated December 26, 2001.

Start Signature

Issued in Renton, Washington, on December 5, 2003.

Kalene C. Yanamura,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

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[FR Doc. 03-31066 Filed 12-16-03; 8:45 am]

BILLING CODE 4910-13-P