Airworthiness directives: Empresa Brasileira de Aeronautica S.A.,

[Federal Register: October 14, 1998 (Volume 63, Number 198)]

[Proposed Rules]

[Page 55059-55061]

From the Federal Register Online via GPO Access [wais.access.gpo.gov]

[DOCID:fr14oc98-21]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-261-AD]

RIN 2120-AA64

Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-120RT and -120ER Series Airplanes

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 EMBRAER Model EMB-120RT and -120ER series airplanes. This proposal would require repetitive visual inspections to detect discrepancies of the brake assemblies on the main landing gear (MLG), and replacement of the brake assemblies with new brake assemblies, if necessary. This proposal is prompted by reports of fatigue cracking or splitting of the brake stator disk at the cut-out slots. The actions specified by the proposed AD are intended to prevent failure of the brake assemblies of the MLG due to cracking or splitting of the stator disk, which could result in loss of brake effectiveness and could cause the airplane to leave the runway surface.

DATES: Comments must be received by November 13, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 98-NM-261-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 BFGoodrich, Aircraft Wheels and Brakes, P.O. Box 340, Troy, Ohio, 45373. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia.

FOR FURTHER INFORMATION CONTACT: Rob Capezutto, Aerospace Engineer, Systems and Flight Test Branch, ACE-116A, FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone (770) 703-6071; fax (770) 703-6097.

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 filedin 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-261-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-261-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The FAA has received reports indicating that certain EMBRAER Model EMB-120RT and -120ER series airplanes have experienced failures in

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the brake assemblies of the main landing gear (MLG) due to cracking or splitting of the stator disk of the brake assemblies. At this time, the exact cause of the cracking or splitting has not been determined. Such cracking or splitting, if not corrected, could result in loss of brake effectiveness and could cause the airplane to leave the runway surface.

Explanation of Relevant Service Information

The FAA has reviewed and approved BFGoodrich Service Bulletin 2- 1585-32-1, Revision 1, dated June 17, 1998 [for airplanes equipped with brake assembly part number (P/N) 2-1585], and Service Bulletin 2-1479- 32-2, Revision 1, dated June 17, 1998 (for airplanes equipped with brake assembly P/N 2-1479-1). These service bulletins describe procedures for repetitive visual inspections to detect discrepancies (i.e., locking or hanging up, broken or damaged stators, and wear of plates) of the brake assemblies on the MLG. These service bulletins also recommend contacting BFGoodrich in the event that a discrepant brake assembly is detected.

U.S. Type Certification of Airplane

These airplane models are manufactured in Brazil 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.

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, except as discussed below. The proposed AD also would require that operators report results of the inspection findings to BFGoodrich.

Differences Between Proposed Rule and Service Bulletins

Operators should note that, although the service bulletins specify that BFGoodrich, the manufacturer of the brake assemblies, be contacted if any discrepant brake assembly is detected, this proposal would require replacement of any discrepant brake assembly to be accomplished in accordance with the EMBRAER EMB-120 Brasilia Maintenance Manual.

Interim Action

This is considered to be interim action until final action is identified, at which time the FAA may consider further rulemaking.

Cost Impact

The FAA estimates that 227 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 inspection, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $13,620, or $60 per airplane, per inspection cycle.

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.

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:

   Empresa Brasileira de Aeronautica S.A. (EMBRAER): Docket 98-NM-261- AD.

   Applicability: Model EMB-120RT and -120ER series airplanes, equipped with BFGoodrich brake assemblies having part number (P/N) 2-1585 or 2-1479-1; certificated in any category.

   Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been 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 (d) 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 failure of the brake assemblies of the main landing gear (MLG) due to cracking or splitting of the stator disk, which could result in loss of brake effectiveness and could cause the airplane to leave the runway surface, accomplish the following:

   (a) At the next MLG wheel removal, but no later than 300 landings after the effective date of this AD, perform visual inspections for discrepancies (i.e., locking or hanging up, broken or damaged stators, and wear of plates) of the brake assemblies on the MLG, in accordance with paragraph (a)(1) or (a)(2), of this AD, as applicable. Repeat the inspections thereafter at each wheel change, but not to exceed an interval of 300 landings.

   (1) For airplanes equipped with BFGoodrich main brake assemblies having P/N 2-1479-1: Inspect in accordance with BFGoodrich Service Bulletin 2-1479-32-2, Revision 1, dated June 17, 1998.

   (2) For airplanes equipped with BFGoodrich main brake assemblies having P/N 2-1585: Inspect in accordance with BFGoodrich Service Bulletin 2-1585-32-1, Revision 1, dated June 17, 1998.

   (b) If any discrepancy is detected during any inspection required by paragraph (a) of this AD, prior to further flight, replace the brake assembly with a new brake assembly, in accordance with section 32-41-05 of EMBRAER EMB-120 Brasilia Maintenance Manual, dated April 30, 1992. Repeat the inspections required by paragraph (a) of this AD thereafter at each wheel change, but not to exceed an interval of 300 landings.

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   (c) Within 10 days after accomplishing any inspection required by this AD, if a discrepant brake assembly is detected, submit a report of the inspection results, to BFGoodrich, Aircraft Wheels and Brakes, P.O. Box 340, Troy, Ohio 45373. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

   (d) 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, Atlanta Aircraft Certification Office (ACO), FAA, Small 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, Atlanta ACO.

   Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.

   (e) 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.

   Issued in Renton, Washington, on October 6, 1998. Darrell M. Pederson, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.

   [FR Doc. 98-27461Filed10-13-98; 8:45 am]

   BILLING CODE 4910-13-U