AD 97-01-09 ACTIVE

This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A321 series airplanes. This action requires repetitive inspections to detect cracking and delamination of the doors that contain the left and right emergency evacuation slides located at certain emergency exits; and repair or replacement, if necessary. This action also requires the accomplishment of a modification that serves as terminating action for the repetitive inspections. This amendment is prompted by a report indicating that a slide aboard an airplane deployed during flight and consequently separated from the airplane. The actions specified in this AD are intended to prevent the loss of these slides during flight, which could make certain exits unusable in the event of an emergency, and also damage the empennage.

Final rule; request for comments.

97-01-09 AIRBUS: Amendment 39-9880. Docket 96-NM-166-AD.

Applicability: Model A321 series airplanes; as listed in Airbus Industrie All Operator Telex (AOT) 25-11, Revision 01, dated January 8, 1996, and Airbus Service Bulletin A320-25- 1167, dated June 24, 1996; on which Airbus Modification 25369 has not been installed; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 theunsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent the loss of the left and right emergency evacuation slides at emergency exits Number 2 and 3 during flight, which could make these exits unusable in the event of an emergency and also could cause damage to the empennage, accomplish the following:

(a) Within 500 hours time-in-service after the effective date of this AD, conduct a detailed visual inspection to detect cracking, and a coin tap inspection to detect delamination, of the left and right enclosure doors of the containers in which the emergency evacuation slides are packed ("the blow out doors") at emergency exits Number 2 and 3, in accordance with Airbus Industrie All Operator Telex (AOT) 25-11, dated January 4, 1996; or Revision 01, dated January 8, 1996.

(1) If no crack or delamination is detected, or if any crack or delamination is detected and it does not exceed 3 inches (75 mm) in length: Repeat the inspections thereafter at intervals not to exceed 18 months.

(2) If any crack or delamination is detected, and it is greater than 3 inches (75 mm) in length, but not greater than 10 inches (250 mm) in length: Prior to further flight, repair the door in accordance with the AOT.

(3) If any crack or delamination is detected, and it is greater than 10 inches (250 mm) in length: Prior to further flight, replace the door in accordance with the AOT.

(b) Within 36 months after the effective date of this AD, modify the escape slide system in accordance with Airbus Service Bulletin A320-25-1167, dated June 24, 1996. Accomplishment of this modification constitutes terminating action for the repetitive inspections required by paragraph (a) of this AD.

NOTE 2: Airbus Service Bulletin A320-25-1167 references Air Cruisers Service Bulletin S.B. 005-25-04, dated May 24, 1996, for additional procedural information.

(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 3: 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 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.

(e) The inspections and repair shall be done in accordance with Airbus Industrie All Operator Telex 25-11, dated January 4, 1996; or Airbus Industrie All Operator Telex 25-11, Revision 01, dated January 8, 1996. The modification shall be done in accordance with Airbus Service Bulletin A320-25-1167, dated June 24, 1996. 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 Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, 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.

(f) This amendment becomes effective on January 30, 1997.

The Direction G n rale 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 A321 series airplanes. The DGAC advises that one operator of Model A321 series airplanes reported the loss of an emergency slide during flight. The airplane was climbing through flight level (FL) 200 when a loud noise was heard; it was caused by an escape slide, located at the right Number 2 emergency exit, unfolding and floating in the airstream. After approximately five minutes, the slide was torn off the airplane and lost on ground.

Visual inspection of the slide inflation system's bottle valve gauge revealed that the bottle had not discharged, thereby confirming that the slide inflation system had not been activated inadvertently. Further investigation revealed that the slide enclosure door (referred to commonly as the blow out door ) had been forced open, evidenced by the retained floating pin receptacles of the pneumatic ball locks (which are installed as a back-up device in the event that the pneumatic release fails).

A subsequent inspection of other Model A321 series airplanes in the affected operator's fleet revealed:

1. a blow out door that was damaged on the inside;

2. snap buttons on slide packs that were open; and

3. lacing cord on slide pack covers that was loosened.

These findings established that the loss of the slide during flight was the result of either excessive internal pressure on the blow out door, or excessive pressure to the outside of this door due to an incorrectly adjusted boarding ramp or gangway. (The exit had been used to board passengers.)

Deployment and separation of an emergency evacuation slides at emergency exits Number 2 or 3 during flight could make these exits unusable in the event of an emergency, and also could cause damage to the empennage.

Explanation of Relevant Service Information
Airbus has issued All Operator Telex (AOT) 25-11, dated January 4, 1996, and Revision 01, dated January 8, 1996. These documents describe procedures for conducting repetitive detailed visual and coin tap inspections to detect cracking and delamination of the left and right blow out doors at emergency exits Number 2 and 3. They also describe procedures for necessary repairs if either of these discrepancies are detected during an inspection. If cracking or delamination exceeds certain limits, the AOT s recommend replacement of the affected slide container with a serviceable container prior to further flight.

The DGAC classified the AOT s as mandatory and issued French airworthiness directive (C/N) 96-054-078(B), dated March 13, 1996, in order to assure the continued airworthiness of these airplanes in France.

Additionally, Airbus has issued Service Bulletin A320-25-1167, dated June 24, 1996, which describes a modification of the evacuation system at doors 2 and 3. (This service bulletin references Air Cruisers Service Bulletin S.B. 005-25-04, dated May 24, 1996, for additional procedural information.) Among other things, the modification entails:

1. a revised packing procedure;

2. relocating snaps on the lacing cover;

3. installing longer lanyard straps; and

4. replacing the frangible washers in the blow-out door with solid ring retainers.

This modification will preclude the types of problems associated with the slide system that were previously experienced. The DGAC has classified this service bulletin as "recommended."

FAA's Conclusions
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 (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.

Explanation of Requirements of the 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, this AD is being issued to prevent loss of an evacuation slide during flight. This AD requires repetitive visual and coin tap inspections to detect cracking and delamination of the blow out doors at emergency exits Number 2 and 3; and repair or replacement, as necessary. These actions are required to be accomplished in accordance with either of the Airbus AOT s described previously.
This AD also requires the accomplishment of the modification of the escape slide system in accordance with Airbus Service Bulletin A320-25-1167. This modification constitutes terminating action for the required repetitive inspections.

Differences Between the FAA s Action and the DGAC s Action
Operators should note that this AD requires the modification of the escape slide system as terminating action for the inspections; whereas, the parallel French CN 96-054-078(B) does not require it. The adequacy of inspections needed to maintain the safety of the transport airplane fleet, coupled with a better understanding of the human factors associated with numerous repetitive inspections, has caused the FAA to place less emphasis on repetitive inspections and more emphasis on design improvements and material replacement. Thus, the FAA has decided to require, whenever practicable, modifications necessary to remove the source of the problem addressed. The modification requirement of this AD is in consonance with that decision.

Cost Impact
None of the Airbus Model A321 series airplanes affected by this action are on the U.S. Register. All airplanes included in the applicability of this rule currently are operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, the FAA considers that this rule is necessary to ensure that the unsafe condition is addressed in the event that any of these subject airplanes are imported and placed on the U.S. Register in the future.

Should an affected airplane be imported and placed on the U.S. Register in the future, it would require approximately 2 work hours to accomplish the required inspections, at an average labor charge of $60 per work hour. Based on these figures, the cost impact of the inspection requirements of this AD would be $120 per airplane per inspection.

Accomplishment of the required terminating modification would take approximately 5 work hours, at an average labor charge of $60 per work hour. Required parts would cost would be provided at no charge to operators by the manufacturer of the slide system (Air Cruisers Company). Based on these figures, the costimpact of the modification requirements of this AD would be $300 per airplane.

Determination of Rule's Effective Date
Since this AD action does not affect any airplane that is currently on the U.S. register, it has no adverse economic impact and imposes no additional burden on any person. Therefore, prior notice and public procedures hereon are unnecessary and the amendment may be made effective in less than 30 days after publication in the Federal Register.

Comments Invited
Although this action is in the form of a final rule and was not preceded by notice and 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 96-NM-166-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Impact
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.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action and it is contained in theRules Docket. A copy of it 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. 106(g), 40113, 44701.
39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-103, Attention: Rules Docket No. 96-NM-166-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

The service information referenced in this AD 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; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Charles Huber, Aerospace Engineer, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 227-2589; fax (206) 227-1149.