Airworthiness Directives; Aerospatiale Model ATR 42-300 and -320 Series Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-99-AD; Amendment 39-8981; AD 94-15-10]

Airworthiness Directives; Aerospatiale Model ATR 42-300 and -320

Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

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SUMMARY: This amendment adopts a new airworthiness directive (AD) that

is applicable to certain Aerospatiale Model ATR42-300 and -320 series

airplanes. This action requires an inspection to verify that the cables

supplying power to the aileron trim are adequately protected and to

detect any damage to these cables. This amendment also requires

installation of protective sleeves on unprotected cables, and

replacement of damaged cables. This amendment is prompted by reports of

a short circuit of these cables due to worn protective sleeves. The

actions specified in this AD are intended to prevent short circuiting

of the cables that supply power to the aileron trim, which could lead

to loss of aileron trim control.

DATES: Effective August 11, 1994.

The incorporation by reference of certain publications listed in

the regulations is approved by the Director of the Federal Register as

of August 11, 1994.

Comments for inclusion in the Rules Docket must be received on or

before September 26, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

Administration (FAA), Transport Airplane Directorate, ANM-103,

Attention: Rules Docket No. 94-NM-99-AD, 1601 Lind Avenue, SW., Renton,

Washington 98055-4056.

The service information referenced in this AD may be obtained from

Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 03, France.

This information may be examined at the FAA, Transport Airplane

Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the

Office of the Federal Register, 800 North Capitol Street, NW., suite

700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Sam Grober, Aerospace Engineer,

Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,

1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206)

227-1187; fax (206) 227-1320.

SUPPLEMENTARY INFORMATION: The Direction Generale de l'Aviation Civile

(DGAC), which is the airworthiness authority for France, recently

notified the FAA that an unsafe condition may exist on certain

Aerospatiale Model ATR42-300 and -320 series airplanes. The DGAC

advises that the cables that supply power to the aileron trim short-

circuited on an in-service airplane. Investigation revealed that the

protective sleeve on these cables was worn. Short circuiting of the

cables that supply power to the aileron trim, if not corrected, could

result in loss of aileron trim control.

Avions de Transport Regional has issued Service Bulletin ATR42-27-

0070, dated December 20, 1993, which describes procedures for visually

inspecting to verify that the protective sleeve on the cables that

supply power to the aileron trim adequately protect the cables, and to

detect damaged cables. This service bulletin also contains instructions

for replacing damaged cables with cables that have been modified in

accordance with Avions de Transport Regional Service Bulletin ATR42-27-

0014, Revision 2, dated December 20, 1993. This latter service bulletin

describes procedures for installation of protective sleeves

(Modification A0014) on cables that are not adequately protected. The

DGAC classified these service bulletins as mandatory and issued French

Airworthiness Directive 94-004-054(B), dated January 5, 1994, in order

to assure the continued airworthiness of these airplanes in France.

This airplane model is manufactured in France and is type

certificated for operation in the United States under the provisions of

Sec. 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the

applicable bilateral airworthiness agreement. Pursuant to this

bilateral airworthiness agreement, the DGAC has kept the FAA informed

of the situation described above. The FAA has examined the findings of

the DGAC, 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.

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 loss of

aileron trim control due to a short circuit in the cables that supply

power to the aileron trim. This AD requires visually inspecting to

verify that the cables that supply power to the aileron trim are

adequately protected, and to detect damaged cables; replacing damaged

cables with cables that have been previously modified; and installing

protective sleeves on unprotected cables. The actions are required to

be accomplished in accordance with the service bulletins described

previously.

This AD applies only to airplanes having manufacturer's serial

numbers 003 through 072. For airplanes having manufacturer's serial

numbers 073 and subsequent, a glass fabric adhesive tape has been

applied to the cables prior to delivery of the airplane; therefore,

these airplanes are not subject to the unsafe condition addressed by

this AD action.

Since a situation exists that requires the immediate adoption 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 of the

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 94-NM-99-AD.'' The postcard will be date stamped and

returned to the commenter.

The regulations adopted herein will 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 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 under the 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. App. 1354(a), 1421 and 1423; 49 U.S.C.

106(g); and 14 CFR 11.89.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding the following new

airworthiness directive:

94-15-10 AEROSPATIALE: Amendment 39-8981. Docket 94-NM-99-AD.

Applicability: Model ATR42-300 and -320 series airplanes having

manufacturer's serial numbers 003 through 072, inclusive,

certificated in any category.

Compliance: Required as indicated, unless accomplished

previously.

To prevent loss of aileron trim control due to short circuiting

of the cables that supply power to the aileron trim, accomplish the

following:

(a) Within 90 days after the effective date of this AD, perform

a visual inspection to verify that the cables, which supply power to

the aileron trim, are adequately protected, in accordance with

Avions de Transport Regional Service Bulletin ATR42-27-0070, dated

December 20, 1993.

(b) If the cables are adequately protected, no further action is

required by this AD.

(c) If any cable is not adequately protected, prior to further

flight, perform a visual inspection to detect damage to the

unprotected cable, in accordance with Avions de Transport Regional

Service Bulletin ATR42-27-0070, dated December 20, 1993.

(1) For any undamaged cable: Within 90 days after the effective

date of this AD, install protective sleeves (Modification A0014) on

the undamaged, unprotected cable, in accordance with Avions de

Transport Regional Service Bulletin ATR42-27-0014, Revision 2, dated

December 20, 1993.

(2) For any damaged cable: Prior to further flight, replace the

damaged cable in accordance with Avions de Transport Regional

Service Bulletin ATR42-27-0070, dated December 20, 1993, with

cabling that has been previously modified (Modification A0014) in

accordance with Avions de Transport Regional Service Bulletin ATR42-

27-0014, Revision 2, dated December 20, 1993.

(d) 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, Standardization Branch, ANM-113,

FAA, Transport 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,

Standardization Branch, ANM-113.

Note: Information concerning the existence of approved

alternative methods of compliance with this AD, if any, may be

obtained from the Standardization Branch, ANM-113.

(e) 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.

(f) The inspection and replacement shall be done in accordance

with Avions de Transport Regional Service Bulletin ATR42-27-0070,

dated December 20, 1993. The installation shall be done in

accordance with Avions de Transport Regional Service Bulletin ATR42-

27-0014, Revision 2, dated December 20, 1993. 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 Aerospatiale, 316 Route de Bayonne, 31060 Toulouse,

Cedex 03, France. Copies may be inspected at the FAA, Transport

Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or

at the Office of the Federal Register, 800 North Capitol Street,

NW., suite 700, Washington, DC.

(g) This amendment becomes effective on August 11, 1994.

Issued in Renton, Washington, on July 18, 1994.

S.R. Miller,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-17856 Filed 7-26-94; 8:45 am]

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