Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-135 and -145 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-135 and -145 series airplanes. This proposal would require replacing the electrical harness for the tail boom strobe light with a new, improved harness that has a built-in metallic overbraid, and performing an operational test following the replacement. This action is necessary to ensure that there is sufficient lightning bonding at the electrical harness for the tail boom strobe light, and to prevent the simultaneous failure of multiple avionics systems in the event of a lightning strike, which could result in reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by June 7, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2004-NM-47-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. 2004-NM-47-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 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.

FOR FURTHER INFORMATION CONTACT:

Todd Thompson, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-1175; 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 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 2004-NM-47-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. 2004-NM-47-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-135 and -145 series airplanes. The DAC advises that operators have reported damage to several components of the electrical system, which was caused by lightning strikes to the fuselage. Investigation revealed that the root cause of the damage is an insufficient bonding at the electrical harness for the tail boom strobe light. A lightning strike in this area could lead to the simultaneous failure of multiple avionics systems, which could result in reduced controllability of the airplane.

Explanation of Relevant Service Information

EMBRAER has issued Service Bulletin 145-33-0032, dated November 5, 2003 (for Model EMB-135 and -145 series airplanes, except Model EMB-135BJ series airplanes); and Service Bulletin 145LEG-33-0004, dated November 5, 2003 (for Model EMB-135BJ series airplanes).

These service bulletins describe procedures for replacing the tail boom strobe light electrical harness with a new, improved harness that has a built-in metallic overbraid. The replacement includes cleaning the affected area; installing a new harness and a new grommet; and performing an operational test of the navigation lights and anti-collision light following the replacement. Accomplishment of the actions specified in the service bulletins is intended to adequately address the identified unsafe condition.

The DAC classified these service bulletins as mandatory and issued Brazilian airworthiness directive 2004-01-05, dated February 5, 2004, to ensure 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 service bulletins described previously, except as discussed below.

Difference Between Proposed Rule and Brazilian Airworthiness Directive

Brazilian airworthiness directive 2004-01-05, dated February 5, 2004, is applicable to “all EMB-145 ( ) and EMB-135 ( ) aircraft models in operation.” However, this does not agree with EMBRAER Service Bulletin 145-33-0032, dated November 5, 2003, and Service Bulletin 145LEG-33-0004, dated November 5, 2003, which state that only certain EMB-145 and EMB-135 series airplanes are affected and identifies them by serial number. This proposed AD would be applicable only to the airplanes listed in the service bulletins. This difference has been coordinated with the DAC.

Cost Impact

We estimate that 548 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 2 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 $915 and $1,255 per airplane, depending upon the airplane configuration. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be between $572,660 and $758,980, or between $1,045 and $1,385 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. 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.

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.