00-16236. Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-120, EMB-120ER, and EMB-120RT 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-120, EMB-120ER, and EMB-120RT series airplanes. This proposal would require removal of a certain fastener, if applicable, and sealing of the corresponding fastener hole. This action is necessary to prevent contact between one of the bolts that attaches the direct current (DC) relay box on the left-hand side of the airplane and one of the power terminals of electrical emergency contactor 2, which could result in a short circuit in the DC relay box, and consequent partial loss of the electrical system, and degraded operation of airplane systems. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by July 27, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-122-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 [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2000-NM-122-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 Empresa Brasileira de Aeronautica S.A. (EMBRAER), P.O. Box 343—CEP 12.225, Sao Jose dos Campos—SP, Brazil. 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:

Carla Worthey, Program Manager, Program Management and Systems Branch, ACE-118A, FAA, Small Airplane Directorate, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone [phone]; fax [phone].

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.

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 notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2000-NM-122-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. 2000-NM-122-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Departmento de Aviacao Civil (DAC), which is the airworthiness authority for Brazil, notified the FAA that an unsafe condition may exist on certain EMBRAER Model EMB-120, EMB-120ER, and EMB-120RT series airplanes. The DAC advises that one of the bolts that attaches the direct current (DC) relay box on the left-hand side of the airplane (hereinafter referred to as the “LH DC relay box”) is located close enough to one of the power terminals of electrical emergency contactor 2 (K0519) that contact between the bolt and the contactor may occur. This condition, if not corrected, could result in a short circuit in the LH DC relay box, and consequent partial loss of the electrical system and degraded operation of airplane systems.

Explanation of Relevant Service Information

EMBRAER has issued Alert Service Bulletin 120-24-A057, dated November 14, 1996, which describes procedures for removal of a certain bolt and washer on the LH DC relay box in the vicinity of electrical emergency contactor 2 (K0519), if applicable, and sealing of the corresponding fastener hole. If no bolt and washer is installed, the alert service bulletin describes procedures for sealing of the corresponding fastener hole only. Accomplishment of the actions specified in the alert service bulletin is intended to adequately address the identified unsafe condition. The DAC classified this alert service bulletin as mandatory and issued Brazilian airworthiness directive 96-12-02, dated December 13, 1996, in order to assure the continued airworthiness of these airplanes in Brazil.

FAA's Conclusions

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. Pursuant to this bilateral airworthiness agreement, the DAC has kept the FAA informed of the situation described above. The FAA has examined the findings of the DAC, 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 alert service bulletin described previously.

Cost Impact

The FAA estimates that 240 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 actions, 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 $14,400, or $60 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.

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.

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.

§ 39.13

[Amended]

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

Empresa Brasileira de Aeronautica S.A. (EMBRAER): Docket 2000-NM-122-AD.

Applicability: Model EMB-120, EMB-120ER, and EMB-120RT series airplanes; serial numbers 120004 and 120006 through 120321 inclusive; certificated in any category; on which EMBRAER Service Bulletin 120-24-0051, dated March 1, 1994, Revision 1, dated May 5, 1994, Revision 2, dated May 31, 1994, Revision 3, dated November 3, 1994, or Revision 4, dated March 8, 1995, or the production equivalent, has been accomplished.

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 contact between one of the bolts that attaches the direct current (DC) relay box on the left-hand (LH) side of the airplane (hereinafter referred to as the “LH DC relay box”) and one of the power terminals of electrical emergency contactor 2 (K0519), which could result in a short circuit in the LH DC relay box, and consequent partial loss of the electrical system, and degraded operation of airplane systems, accomplish the following:

Bolt/Washer Removal and Hole Sealing

(a) Within 75 flight hours after the effective date of this AD, remove the bolt and washer on the LH DC relay box that is in the area of electrical emergency contactor 2 (K0519) and seal the corresponding fastener hole, in accordance with EMBRAER Alert Service Bulletin 120-24-A057, dated November 14, 1996. If no fastener is installed, seal the corresponding fastener hole only, in accordance with the alert service bulletin.

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, 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.

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 Brazilian airworthiness directive 96-12-02, dated December 13, 1996.

Issued in Renton, Washington, on June 21, 2000.

Donald L. Riggin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.