00-31318. Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-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-145 series airplanes. This proposal would require inspection of the bolts on the hinge fittings that attach the spring tab and the servo tab to the rear spar of the elevators for evidence of loosening; inspection of the region of the hinge fittings on the spring tab for interference of the bonding jumpers attached to the hinge fittings with the leading edge of the spring tab; and corrective action, if necessary. The proposal is prompted by issuance of mandatory continuing airworthiness information by a foreign airworthiness authority. The action specified by the proposed AD is intended to prevent the spring tab or the servo tab from becoming disconnected, resulting in structural failure. The action is also intended to prevent damage to the leading edge of the spring tab, which could result in loss of control of the elevator.

DATES:

Comments must be received by January 8, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2000-NM-256-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. 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-256-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, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 450, Atlanta, Georgia.

FOR FURTHER INFORMATION CONTACT:

Viswa Padmanabhan, Aerospace Engineer, ACE-117A, FAA, 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 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 2000-NM-256-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-256-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-145 series airplanes. The DAC reported an instance of the loosening of the bolts on the hinge fittings which attach the spring tab and the servo tab to the rear spar of the elevators and indicated that the resulting loss of attachment rigidity may lead to undesirable levels of vibration. The DAC also notified the FAA that the bonding jumpers held in position by bolts on the hinge fittings may interfere with the leading edge of the spring tab.

The actions specified by the proposed AD are intended to prevent the spring tab or the servo tab from becoming disconnected, resulting in structural failure. The actions are also intended to prevent damage to the leading edge of the spring tab, which could result in loss of control of the elevator.

Explanation of Relevant Service Information

EMBRAER has issued Service Bulletin 145-55-0009, Change No. 02, dated May 19, 2000, which describes procedures for a one-time inspection of the bolts on the hinge fittings that attach the spring tab and the servo tab to the rear spars of the elevators for evidence of loosening. The service bulletin also describes procedures for a one-time inspection of the region of the hinge fittings on the spring tab for interference of the bonding jumpers with the leading edge of the spring tab.

If no discrepancies are found, operators must perform follow-up repetitive inspections as specified in the service bulletin. If discrepancies are found, operators must perform modifications, such as replacing the bolts with improved bolts, installing washers, installing lockwire or changing its position, and changing the position of the bonding jumpers. Accomplishment of the actions specified in the service bulletin is intended to adequately address the identified unsafe condition.

The DAC issued Brazilian airworthiness directive 98-05-02, dated May 28, 1998, which referred to Embraer Service Bulletin 145-55-0009, initial release or further revisions approved by the Brazilian airworthiness authority.

FAA's Conclusions

This airplane model is manufactured in Brazil and is type certificated for operation in the United States under the provisions of § 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 bulletin described previously, except as described below.

Differences Between Proposed Rule and Service Bulletin/Brazilian Airworthiness Directive

The intervals between repetitive inspections in the proposed AD (stated in flight hours) differ from those recommended in the manufacturer's service bulletin (stated to coincide with operators' “A” checks). However, because regularly scheduled maintenance intervals, such as “A” checks, may vary from operator to operator, there would be no assurance that the inspections would be accomplished during the maximum intervals proposed by this AD. These intervals are intended to maintain an adequate level of safety within the fleet.

Another difference concerns the compliance time for accomplishment of the terminating action. The manufacturer's service bulletin recommends that, if no discrepancy is found during the initial inspection described in Part I, the terminating action described in Part II, III, or IV may be accomplished at any time, at the operator's discretion. However, the FAA has determined that requiring a specific compliance time is necessary to adequately address the identified unsafe condition. In developing an appropriate compliance time for this proposed AD, the FAA considered not only the manufacturer's recommendation, but also the degree of urgency associated with addressing the subject unsafe condition and the average utilization of the affected fleet. In light of these factors, the FAA finds a compliance time of 2,000 flight hours for accomplishing the terminating actions to be warranted, in that it represents an appropriate interval of time allowable for affected airplanes to continue to operate without compromising safety.

Finally, Brazilian airworthiness directive 98-05-02 refers to EMBRAER Service Bulletin 145-55-0009, initial release, or further revision approved by the Brazilian airworthiness authority. The proposed AD refers to EMBRAER Service Bulletin 145-55-0009, Change No. 2, dated May 19, 2000, which includes procedures for repetitive inspections for interference between the bonding jumpers and the leading edge of the spring tab.

Cost Impact

The FAA estimates that 71 airplanes of U.S. registry would be affected by this proposed AD.

The initial inspection would take 2 work hours per airplane at an average labor rate of $60 per hour. Based on these figures, the cost impact on U.S. operators of the initial inspection (Part I) specified in the proposed AD is estimated to be $8,520, or $120 per airplane.

The cost impact on U.S. operators of follow-on actions is specified in the following table:

Cost of follow-on actions

Action	Work hours	Cost of labor/airplane	Cost of parts/airplane	Cost/airplane
Corrective action/ Part II	6	$360	$71	$431
Corrective action/ Part III	6	360	2	362
Repetitive inspection/ Part IV	3	180	0	180

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 proposed 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.

§ 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-256-AD.

Applicability: Model EMB-145 series airplanes; serial numbers 145004 through 145103 inclusive, 145105 through 145111 inclusive, and 145113 through 145117 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 (e) 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 the spring tab or the servo tab from becoming disconnected, resulting in structural failure, and to prevent damage to the leading edge of the spring tab, which could result in loss of control of the elevator, accomplish the following:

Inspection

(a) Within 200 flight hours after the effective date of this AD, conduct a detailed visual inspection, as specified in paragraph (a)(1) or (a)(2) of this AD, as applicable, in accordance with the Accomplishment Instructions of EMBRAER Service Bulletin 145-55-0009, Change No. 02, dated May 19, 2000.

(1) For airplanes having serial numbers 145004 through 145055 that have not been modified in accordance with EMBRAER Service Bulletin 145-55-0009, dated April 7, 1998: Inspect the bolts attaching the spring tab and servo tab hinge fittings to the rear spar of the left-hand and right-hand elevators for evidence of loosening.

(2) For airplanes having serial numbers 145004 through 145103, 145105 through 145111, and 145113 through 145117: Inspect the region of the hinge fittings on the spring tab for interference of the bonding jumper on the attaching bolts with the leading edge of the spring tab.

Note 2:

For the purposes of this AD, a detailed visual inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”

Modification

(b) Perform follow-on corrective actions, as applicable, in accordance with EMBRAER Service Bulletin 145-55-0009, Change No. 02, dated May 19, 2000, as shown in the following table:

Table 1.—Follow-on Corrective Actions

If * * *	And * * *	And * * *	Then * * *
(1) No discrepancy is found			Prior to further flight, seal the bolt heads and adjacent hinge fitting surfaces.
(2) Any loose bolt or any interference of the bonding jumpers with the leading edge of the spring tab is found	The airplanes have serial numbers 145004 through 145055, inclusive	The airplanes have not been modified in accordance with EMBRAER Service Bulletin 145-55-0009, dated April 7, 1998	Prior to further flight, accomplish Part II of the service bulletin, including replacing bolts, adding washers, and changing the position of the lockwire and the bonding jumpers.
	The airplanes have serial numbers 145004 through 145055, inclusive, and 145056 through 145076, inclusive	The airplanes have been modified in accordance with EMBRAER Service Bulletin 145-55-0009, dated April 7, 1998	Prior to further flight, accomplish Part III of the service bulletin, including adding washers and changing the position of the lockwire and the bonding jumpers.
	The airplanes have serial numbers 145077 through 145103, inclusive; 145105 through 145111, inclusive; and 145113 through 145117, inclusive		Prior to further flight, accomplish Part IV of the service bulletin, including adding washers and changing the position of the lockwire and the bonding jumpers.

Repetitive Inspections

(c) Repeat the detailed visual inspection specified in paragraph (a) of this AD, at intervals not to exceed 400 flight hours.

Terminating Action

(d) Within 2,000 flight hours from the effective date of this AD, accomplish Part II, III, or IV, as applicable, of the service bulletin.

Alternative Methods of Compliance

(e) 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. 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

(f) Special flight permits may be issued in accordance with §§ 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 4:

A portion of the subject of this AD is addressed in Brazilian airworthiness directive No. 98-05-02, dated May 28, 2000.

Issued in Renton, Washington, on December 4, 2000.

Donald L. Riggin,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.