Airworthiness Directives; Airbus Industrie Model A320 Series Airplanes

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 94-NM-08-AD]

Airworthiness Directives; Airbus Industrie Model A320 Series

Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing

airworthiness directive (AD), applicable to certain Airbus Industrie

Model A320 series airplanes, that currently requires modification of

the belly fairing structure. This action would revise the compliance

time for accomplishment of the modification. All other parts of the

rule would remain unchanged. The actions specified by the proposed AD

are intended to ensure that the structural integrity of the belly

fairing structure is maintained.

DATES: Comments must be received by March 21, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

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

Attention: Rules Docket No. 94-NM-08-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-08-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-08-AD, 1601 Lind Avenue SW., Renton, Washington 98055-

4056.

Discussion

On December 6, 1993, the FAA issued AD 93-24-11, Amendment 39-8760

(58 FR 64875, December 10, 1993), applicable to certain Airbus

Industrie Model A320 series airplanes, to require modification of the

belly fairing structure. That action was prompted by results of fatigue

testing, which revealed that rivet heads were sheared off and fatigue

cracks were present in the angles at the angle attachment between the

keelbeam and the belly fairing support frames. The requirements of that

AD are intended to prevent reduced structural integrity of the belly

fairing structure.

Since the issuance of that AD, the FAA has become aware that the

compliance time specified in paragraph (a) of AD 93-24-11 for

accomplishment of the modification could allow certain operators to

accomplish the modification at a time considerably later than that

intended. Paragraph (a) of that AD currently requires that the

modification be accomplished prior to the accumulation of 12,000 total

landings after January 10, 1994 (the effective date of AD 93-24-11,

Amendment 39-8760), or within 300 days after that date, whichever

occurs later. However, the FAA's intent is that the modification be

accomplished prior to the accumulation of 12,000 total landings on the

airplane, or within 300 days after the effective date of the AD,

whichever occurs later. The FAA has determined that AD 93-24-11 must be

superseded to revise the compliance time in order to ensure that the

structural integrity of the belly fairing structure is maintained in a

timely manner. All other parts of the rule would remain as published

originally.

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 and the applicable

bilateral airworthiness agreement. The FAA has determined that AD

action is necessary for products of this type design that are

certificated 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 supersede AD 93-24-11 to

continue to require modification of the belly fairing structure. This

proposed AD would revise the compliance time to require accomplishment

of that modification prior to the accumulation of 12,000 total landings

on the airplane, or within 300 days after January 10, 1994, whichever

occurs later. The actions would continue to be required to be

accomplished in accordance with Airbus Industrie Service Bulletin A320-

53-1014, dated June 25, 1992, or Revision 1, dated May 26, 1993.

The FAA estimates that 20 airplanes of U.S. registry were affected

by AD 93-24-11, and would continue to be affected by this proposed

supersedure of that AD. It takes approximately 288 work hours per

airplane to accomplish the actions currently required by AD 93-24-11,

and the average labor rate is $55 per work hour. Required parts cost

approximately $1,045 per airplane. Based on these figures, the current

cost impact of AD 93-24-11 on U.S. operators is estimated to be

$337,700, or $16,885 per airplane.

The total cost figure indicated above is presented as if no

operator has yet accomplished the requirements of AD 93-24-11 (or this

proposed supersedure of that AD). There are no foreseeable additional

costs that would be imposed by this proposed supersedure of AD 93-24-

11.

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 removing amendment 39-8760 (58 FR

64875, December 10, 1993), and by adding a new airworthiness directive

(AD), to read as follows:

Airbus Industrie: Docket 94-NM-08-AD. Supersedes AD 93-24-11,

Amendment 39-8760.

Applicability: Model A320 series airplanes, MSN 003 through 092

inclusive, certificated in any category.

Compliance: Required as indicated, unless accomplished

previously.

To prevent reduced structural integrity of the belly fairing

structure, accomplish the following:

(a) Prior to the accumulation of 12,000 total landings on the

airplane, or within 300 days after January 10, 1994 (the effective

date of AD 93-24-11, Amendment 39-8760), whichever occurs later:

Modify the belly fairing structure in accordance with Airbus

Industrie Service Bulletin A320-53-1014, dated June 25, 1992, or

Revision 1, dated May 26, 1993.

(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, 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.

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

Federal Aviation Regulations (FAR) 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 January 27, 1994.

James V. Devany,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-2332 Filed 2-1-94; 8:45 am]

BILLING CODE 4910-13-U