Airworthiness Directives; Airbus Model A320 Series Airplanes

DEPARTMENT OF TRANSPORTATION

14 CFR Part 39

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

Airworthiness Directives; Airbus Model A320 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 Airbus Model A320 series

airplanes. This proposal would require repetitive inspections to verify

proper installation of the plain bushings of the upper and lower

connection links on the forward and aft passenger/crew doors, and

correction of discrepancies, if necessary. This proposal would also

require replacement of the shouldered bushing on the locking mechanism

with a new oversized bushing, which would terminate the repetitive

inspection requirements. This proposal is prompted by a report that,

during an emergency evacuation of in-service airplanes, the left aft

passenger/crew door jammed against the fuselage structure in a nearly

closed position due to bushing migration. The actions specified by the

proposed AD are intended to prevent jamming of the passenger/crew door,

which could delay or impede the evacuation of passengers during an

emergency.

DATES: Comments must be received by October 25, 1994.

ADDRESSES: Submit comments in triplicate to the Federal Aviation

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

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

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-94-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-94-AD, 1601 Lind Avenue, SW., Renton, Washington

98055-4056.

Discussion

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 Airbus Model A320 series

airplanes. The DGAC advises that, during an emergency evacuation of an

in-service airplane, the left aft passenger/crew door jammed against

the fuselage structure in a nearly closed position. Investigation

revealed the bushing of the lower connection link had migrated. The

cause of this migration has been attributed to the seizing of the upper

locking hook into its bronze bushing from the frame segment at the

level of the door lifting bellcranks. This condition, if not corrected,

could result in jamming of the passenger/crew door, which could delay

or impede the evacuation of passengers during an emergency.

Airbus has issued Service Bulletin A320-52-1047, dated April 25,

1994, which describes procedures for:

1. Performing repetitive detailed visual inspections to verify

proper installation of the plain bushings of the upper and lower

connection links on the forward and aft passenger/crew doors;

2. Removing the passenger/crew door and inspecting the bushings to

detect damage, if any bushing has migrated;

3. Reinstalling the bushing, if the bushing housings are not

damaged; and

4. Reaming the door structure and installing an oversize shouldered

bushing, if any bushing housing is damaged; and repairing the bushing

housing, if damage is not completely removed.

Airbus has also issued Service Bulletin A320-52-1027, Revision 3,

dated December 10, 1993, which describes procedures for replacing the

shouldered bushing on the locking mechanism with a new oversized

bushing, which will prevent jamming of the passenger/crew door.

The DGAC classified these service bulletins as mandatory and issued

French Airworthiness Directive 93-207-048(B), dated December 8, 1993,

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, the proposed AD would require repetitive detailed

visual inspections to verify proper installation of the plain bushings

of the upper and lower connection links on the forward and aft

passenger/crew doors, and correction of discrepancies, if necessary.

The proposed AD would also require replacement of the shouldered

bushing on the locking mechanism with a new oversized bushing, which

would terminate the repetitive inspection requirements. The actions

would be required to be accomplished in accordance with the service

bulletins described previously. Correction of certain discrepancies

would be required to be accomplished in accordance with a method

approved by the FAA.

The FAA estimates that 99 airplanes of U.S. registry would be

affected by this proposed AD. It would take approximately 72 work hours

per airplane to accomplish the proposed modification at an average

labor rate of $55 per work hour. Required parts would be supplied by

the manufacturer at no cost to the operators. Based on these figures,

the total cost impact of the modification proposed by this AD on U.S.

operators is estimated to be $392,040, or $3,960 per airplane.

It would take approximately 6 work hours per airplane to accomplish

the proposed inspection at an average labor rate of $55 per work hour.

Based on these figures, the total cost impact of the inspection

proposed by this AD on U.S. operators is estimated to be $32,670, or

$330 per airplane.

Based on the above figures, the total cost impact of the inspection

and modification proposed by this AD on U.S. operators is estimated to

be $424,710, or $4,290 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

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:

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

Applicability: Model A320 series airplanes on which Airbus

Modification 22422 (reference Airbus Service Bulletin A320-52-1027)

has not been installed, certificated in any category.

Compliance: Required as indicated, unless accomplished

previously.

To prevent jamming of the passenger/crew door, which could delay

or impede the evacuation of passengers during an emergency,

accomplish the following:

(a) Within 450 flight hours after the effective date of this AD,

perform a detailed visual inspection to verify proper installation

of the plain bushings of the upper and lower connection links on the

forward and aft passenger/crew doors, in accordance with Airbus

Service Bulletin A320-52-1047, dated April 25, 1994.

(1) If all bushings are installed properly, repeat the

inspection thereafter at intervals not to exceed 900 flight hours

until the modification required by paragraph (b) of this AD is

accomplished.

(2) If any bushing has migrated, prior to further flight, remove

the passenger/crew door and visually inspect the bushing to detect

damage, in accordance with the service bulletin.

(i) If the bushing housings are not damaged, prior to further

flight, reinstall the bushing in accordance with the service

bulletin. Repeat the detailed visual inspections thereafter at

intervals not to exceed 450 flight hours until the modification

required by paragraph (b) of this AD is accomplished.

(ii) If any bushing housing is damaged, prior to further flight,

ream the door structure and install an oversize shouldered bushing,

in accordance with the service bulletin. If the damage is not

completely removed after reaming, prior to further flight, repair

the bushing housing in accordance with a method approved by the

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

Directorate.

(b) Within 3,500 flight hours after the effective date of this

AD, replace the shouldered bushing on the locking mechanism with a

new oversized bushing (Kit No. 521027A02), in accordance with Airbus

Service Bulletin A320-52-1027, Revision 2, dated February 18, 1993,

or Revision 3, dated December 10, 1993. Accomplishment of this

modification constitutes terminating action for the repetitive

inspection requirements of this AD.

(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 August 24, 1994.

N.B. Martenson,

Acting Manager, Transport Airplane Directorate, Aircraft Certification

Service.

[FR Doc. 94-21362 Filed 8-29-94; 8:45 am]

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