Airworthiness Directives; Airbus Model A300-600 Series Airplanes

DEPARTMENT OF TRANSPORTATION

14 CFR Part 39

[Docket No. 94-NM-55-AD]

Airworthiness Directives; Airbus Model A300-600 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 Model A300-600 series

airplanes. This proposal would require replacement of certain Feel and

Limitation Computers (FLC) with modified FLC's. This proposal is

prompted by reports that the elevator control on several in-service

airplanes operated with stiffness. The actions specified by the

proposed AD are intended to prevent stiff operation of the elevator

control and undetected loss of the rudder travel limitation function,

which may adversely affect controllability of the airplane.

DATES: Comments must be received by July 15, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

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

Attention: Rules Docket No. 94-NM-55-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.

The service information referenced in the proposed rule may be

obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707

Blagnac Cedex, France. This information may be examined at the FAA,

Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton,

Washington.

FOR FURTHER INFORMATION CONTACT: Stephen Slotte, Aerospace Engineer,

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

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

227-2797; fax (206) 227-1320.

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 94-NM-55-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-103, Attention: Rules

Docket No. 94-NM-55-AD, 1601 Lind Avenue, SW., Renton, Washington

98055-4056.

Discussion

The Direction General de l'Aviation Civile (DGAC), which is the

airworthiness authority for France, recently notified the FAA that an

unsafe condition may exist on certain Airbus Model A300-600 series

airplanes. The DGAC advises that operators of Model A300-600 series

airplanes reported that the elevator control on several in-service

airplanes operated with stiffness. Investigation into the cause of this

stiffness revealed that the Feel and Limitation Computer (FLC) may be

detecting spurious low voltage. This condition, if not corrected, could

result in stiff operation of the elevator control and undetected loss

of the rudder travel limitation function, which may adversely affect

controllability of the airplane.

Airbus has issued Service Bulletin A300-27-6025, dated September

15, 1993, that describes procedures for replacement of certain FLC's

with modified FLC's. These replacement FLC's have been modified in

accordance with Aerospatiale Service Bulletin 35-900-27-013, dated

September 29, 1993 (for FLC's having part number 35-900-2000-200);

Aerospatiale Service Bulletin 35-900-27-012, dated September 29, 1993

(for FLC's having part number 35-900-2000- 201); or Aerospatiale

Service Buletin 35-900-27-016, Revision 1, dated December 15, 1993 (for

FLC's having part number 35-900-3002-302). The Aerospatiale service

bulletins describe procedures for adjustment of the ``UNDERVOLTAGE

DETECTION'' signal with new values to preclude stiff operation of the

elevator control. The DGAC classified the Airbus service bulletin as

mandatory and issued French Airworthiness Directive 94-046-156(B),

dated February 16, 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

Section 21.29 of the Federal Aviation Regulations 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, the proposed AD would require replacement of

certain FLC's with modified FLC's. The actions would be required to be

accomplished in accordance with the Airbus service bulletin described

previously. This proposal is applicable only to those airplanes with

modified FLC's that have serial numbers prior to 755.

Note: On April 26, 1994, the FAA issued AD 94-09-16, Amendment

39-8905 (59 FR 23133, May 5, 1994), which addresses this same unsafe

condition, but applies to airplanes with FLC's that have serial

numbers 755 and subsequent.

The FAA estimates that 35 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 actions, and that the

average labor rate is $55 per work hour. Required parts would be

provided at no cost to the operator. Based on these figures, the total

cost impact of the proposed AD on U.S. operators is estimated to be

$3,850, or $110 per airplane.

The total cost impact figure discussed above is 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 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. 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 14

CFR part 39 of the Federal Aviation Regulations 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:

Airbus Industrie: Docket 94-NM-55-AD.

Applicability: Model A300-600 series airplanes, as listed in

Airbus Industrie Service Bulletin A300-27-6025, dated September 15,

1993; certificated in any category.

-Compliance: Required as indicated, unless accomplished

previously.

To prevent stiff operation of the elevator control and

undetected loss of the rudder travel limitation function, which may

adversely affect controllability of the airplane, accomplish the

following:

(a) Within 1 year after the effective date of this AD, replace

Feel and Limitation Computers (FLC) having part number (P/N) 35-900-

2000-200 or 35-900-2000-201, serial numbers prior to 755; and FLC's

having P/N 35-900-3002-302, all serial numbers; with an FLC that has

been previously modified; in accordance with Airbus Service Bulletin

A300-27-6025, dated September 15, 1993.

(b) As of a date 1 year after the effective date of this AD, no

person shall install, on any airplane, an FLC having P/N 35-900-

2000-200, 35-900-2000-201, or 35-900-3002-302, that has not been

previously modified in accordance with Airbus Service Bulletin A300-

27-6025, dated September 15, 1993.

(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, 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.

(d) Special flight permits may be issued in accordance with

Secs. 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.

Issued in Renton, Washington, on May 12, 1994.

Darrell M. Pederson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-12123 Filed 5-17-94; 8:45 am]

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