AD 99-10-05

This amendment adopts a new airworthiness directive (AD) that is applicable to certain EMBRAER Model EMB-145 series airplanes. This action requires replacement of certain flexible joints and O-rings of the rear fuselage with improved flexible joints and new O-rings. This action also requires installation of new support assemblies to attach to the engine bleed line tubing in the area of the rear fuselage to improve the engine bleed line tubing alignment. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified in this AD are intended to prevent failure of certain flexible joints that attach to the engine bleed lines in the area of the rear fuselage. Failure of these flexible joints could cause damage to the fuel lines leading to the auxiliary power unit, which could result in an increased risk of fire to occur in the rear baggage compartment during flight.

Final rule; request for comments

99-10-05 EMPRESA BRASILEIRA DE AERONAUTICA S.A. (EMBRAER): Amendment 39-11159. Docket 99-NM-93-AD.

Applicability: Model EMB-145 series airplanes, serial numbers 145004 through 145075 inclusive; 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 (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: Requiredas indicated, unless accomplished previously.

To prevent failure of certain flexible joints that attach to the engine bleed lines in the area of the rear fuselage, which could cause damage to the fuel lines leading to the auxiliary power unit, resulting in an increased risk of fire to occur in the rear baggage compartment during flight, accomplish the following:

(a) Within 400 flight hours after the effective date of this AD, replace certain flexible joints (Gamah joints) and O-rings of the rear fuselage with improved flexible joints and new O-rings, and install new support assemblies to attach to the engine bleed line tubing in the area of the rear fuselage to improve the engine bleed line tubing alignment, in accordance with EMBRAER Service Bulletin 145-36-0007, Change 03, dated December 9, 1998.

NOTE 2: Any replacement of certain flexible joints and new O-rings and installation of new support assemblies that have been accomplished prior to the effective date of thisAD, in accordance with EMBRAER Service Bulletin 145-36-0007, dated September 1, 1998, Change 01, dated September 18, 1998, or Change 02, dated November 11, 1998, are considered acceptable for compliance with the applicable action specified in this AD. 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 3: 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. Incorporation by Reference

(d) The actions shall be done in accordance with EMBRAER Service Bulletin 145-36-0007, Change 03, dated December 9, 1998. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Empresa Brasileira de Aeronautica S.A. (EMBRAER), P.O. Box 343 -CEP 12.225, Sao Jose dos Campos - SP, Brazil. Copies may be inspected 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; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

NOTE 4: The subject of this AD is addressed in Brazilian airworthiness directive 98-11-01, dated November 13, 1998.

(e) This amendment becomes effective on May 20, 1999.

The Departmento de Aviacao Civil (DAC), which is the airworthiness authority for Brazil, recently notified the FAA that an unsafe condition may exist on certain EMBRAER Model EMB-145 series airplanes. The DAC advises that failure of certain flexible joints (Gamah joints) in the engine bleed lines has occurred. The cause of the failure has been attributed to the inadequate strength of these flexible joints. These joints could not withstand the hot bleed air pressure produced by both engines and the joints ruptured in an undisclosed area of the airplane and damaged certain airplane systems. This condition, if not detected and corrected, could result in an increased risk of fire to occur in the rear baggage compartment during flight.

Explanation of Relevant Service Information
EMBRAER has issued Service Bulletin 145-36-0007, Change 03, dated December 9, 1998, which describes procedures for replacement of certain flexible joints (Gamah joints) and O-rings of the rear fuselage with improved flexible joints and new O-rings. The service bulletin also describes procedures for installation of new support assemblies to attach to the engine bleed line tubing in the area of the rear fuselage to improve the engine bleed line tubing alignment. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

The DAC classified this service bulletin as mandatory and issued Brazilian airworthiness directive 98-11-01, dated November 13, 1998, in order to assure the continued airworthiness of these airplanes in Brazil.

FAA's Conclusions
This airplane model is manufactured in Brazil and is 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 informedof 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 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, this AD is being issued to prevent failure of certain flexible joints that attach to the engine bleed lines in the area of the rear fuselage. Failure of these flexible joints could cause damage to the fuel lines leading to the auxiliary power unit, which could result in an increased risk of fire to occur in the baggage compartment during flight. This AD requires accomplishment of the actions specified in the service bulletin described previously.

Determination of Rule's Effective Date
Since a situation exists that requires the immediateadoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this 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 under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness ofthe AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the 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 that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 99-NM-93-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Impact
The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national governmentand 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 final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided underthe caption "ADDRESSES."

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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: