Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. (EMBRAER) Model EMB-145 Series Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-34-AD]

RIN 2120-AA64

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).

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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 a one-time visual

inspection of the pilot valve harness tubes for bulges and cracks,

cleaning the tubes, applying sealant at the tube end opening, and

replacing any discrepant tubes with serviceable tubes. This proposal

also would require replacement of the pilot valve harness tubes and

vent valve tubes with new tubes having improved anti-corrosion

protection. This proposal is prompted by issuance of mandatory

continuing airworthiness information by a foreign civil airworthiness

authority. The actions specified by the proposed AD are intended to

prevent cracking of the pilot valve harness tubes, which could allow

fuel to enter the conduit and leak overboard; this condition could

result in increased risk of a fuel tank explosion and fire.

DATES: Comments must be received by April 27, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Transport Airplane Directorate, ANM-114,

Attention: Rules Docket No. 98-NM-34-AD, 1601 Lind Avenue, SW., Renton,

Washington 98055-4056. Comments may be inspected at this

[[Page 14854]]

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 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: Rob Capezzuto, Aerospace Engineer,

ACE-115A, FAA, Small Airplane Directorate, Atlanta Aircraft

Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite

450, Atlanta, Georgia 30337-2748; 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 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 98-NM-34-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-34-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

advises that cracks have been detected in the pilot valve harness tube

(conduit) inside the wing, close to rib 15. The cracking is the result

of water entering the tube at the end opening in the rear spar, then

freezing and expanding. Such cracking can allow fuel to enter the tube,

wet the harness, and drain overboard. This condition, if not corrected,

could result in increased risk of a fuel tank explosion and fire.

Explanation of Relevant Service Information

EMBRAER has issued Service Bulletin 145-28-0005, dated May 23,

1997, which describes procedures for a one-time visual inspection of

the pilot valve harness tubes (conduit) at its lower segment for bulges

and cracks, cleaning the tubes to remove any water, applying sealant at

the tube opening at wing spar II around the harness, and replacing any

discrepant tubes with new or serviceable tubes.

EMBRAER has also issued Service Bulletin 145-28-0006, dated October

22, 1997, which describes procedures for replacement of the existing

pilot valve harness tubes and vent valve tubes with new tubes having

improved anti-corrosion protection. Accomplishment of the actions

specified in this service bulletin is intended to adequately address

the identified unsafe condition.

The DAC classified these service bulletins as mandatory and issued

Brazilian airworthiness directive 97-07-02R1, dated January 15, 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 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.

Cost Impact

The FAA estimates that 15 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 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

$1,800, or $120 per airplane.

It would take approximately 8 work hours per airplane to accomplish

the proposed replacement, at an average labor rate of $60 per work

hour. Required parts would be provided by the manufacturer at no cost

to the operator. Based on these figures, the cost impact of the

proposed replacement on U.S. operators is estimated to be $7,200, or

$480 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.

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.

[[Page 14855]]

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-34-

AD.

Applicability: Model EMB-145 series airplanes; as listed in

EMBRAER Service Bulletin 145-28-0005, dated May 23, 1997, and

EMBRAER Service Bulletin 145-28-0006, dated October 22, 1997;

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 (c) 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 cracking of the pilot valve harness tubes, which

could allow fuel to enter the conduit and leak overboard, and result

in increased risk of a fuel tank explosion and fire, accomplish the

following:

(a) Within 30 calendar days or 200 hours time-in-service after

the effective date of this AD, whichever occurs later, perform a

one-time visual inspection of the pilot valve harness tubes

(conduit) for bulges and cracks, in accordance with the

Accomplishment Instructions of EMBRAER Service Bulletin 145-28-0005,

dated May 23, 1997.

(1) If no discrepancy is found in the harness tube, prior to

further flight, clean the tube and apply sealant at the tube end

opening in accordance with the service bulletin.

(2) If any crack or bulge is found in the harness tube, prior to

further flight, replace the tube with a new or serviceable tube,

clean the tube, and apply sealant at the tube end opening in

accordance with the service bulletin.

(b) Within 4,000 hours time-in-service after the effective date

of this AD, replace the existing pilot valve harness tubes and vent

valve tubes with new tubes, in accordance with EMBRAER Service

Bulletin 145-28-0006, dated October 22, 1997.

(c) 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.

(d) 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 97-07-02R1, dated January 15, 1998.

Issued in Renton, Washington, on March 23, 1998.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 98-8098 Filed 3-26-98; 8:45 am]

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