AD 95-13-01

This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A320 series airplanes, that requires inspections to determine the gap of the seat track joints at frame 64, and correction of discrepancies. This amendment also requires eventual modification of the seat tracks on all affected airplanes, which terminates the requirement of repetitively removing or repositioning the seats. This amendment is prompted by in-service inspection reports, which have revealed that a gap between the forward and aft seat track at frame 64 could exceed the tolerance limit due to a method used on the assembly line to control the position of the seat track. The actions specified by this AD are intended to ensure that the gap of the seat track joints do not exceed the tolerance limit and subsequently lead to separation of the passenger seats from the seat track under emergency landing conditions.

Final rule.

95-13-01 AIRBUS INDUSTRIE: Amendment 39-9281. Docket 94-NM-148-AD.

Applicability: Model A320 series airplanes; manufacturer's serial numbers 002 through 008 inclusive, 010 through 014 inclusive, 016 through 078 inclusive, 080 through 122 inclusive, 124 through 179 inclusive, 183 through 194 inclusive, 196 through 228 inclusive, 230 through 251 inclusive, and 253 through 255 inclusive; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been 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 use the authority provided in paragraph (d) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To prevent separation of the passenger seats from the seat track during an emergency landing, accomplish the following:

(a) Within 450 flight cycles after the effective date of this AD, perform a visual inspection to determine if a seat fitting having an x-plunger behind a z-stud is installed at the seat track joint at frame 64, in accordance with Airbus All Operator Telex (AOT) 53-01, dated August 27, 1992.

(b) If such a seat fitting is installed, prior to further flight, measure the gap between the forward and aft seat tracks at frame 64, in accordance with the Airbus AOT 53-01, dated August 27, 1992.

(1) If the gap is less than or equal to 2.8 mm, prior to further flight, apply sealing material at the seat tracks, in accordance with the AOT.

(2) If the gap is greater than 2.8 mm, prior to further flight, accomplish the requirements of either paragraph (b)(2)(i) or (b)(2)(ii) of this AD, as applicable.
(i) For airplanes equipped with passenger seats at frame 64: Accomplish either paragraph (b)(2)(i)(A) or (b)(2)(i)(B) of this AD:

(A) Remove or reposition the seat in accordance with Airbus AOT 53-01, dated August 27, 1992. Thereafter, repeat the removal or repositioning whenever the cabin configuration is changed until the accomplishment of paragraph (c) of this AD. Or

(B) Modify the seat tracks in accordance with Airbus Service Bulletin A320-53-1088, Revision 3, dated March 27, 1994. Such modification constitutes terminating action for the requirements of this AD.

NOTE 2: Modification of the seat tracks priorto the effective date of this amendment in accordance with Airbus Service Bulletin A320-53-1088, original issue through Revision 2, is considered acceptable for compliance with the applicable actions specified in this paragraph.

(ii) For airplanes equipped with equipment other than passenger seats at frame 64: Prior to further flight, correct the discrepancy in accordance with a method approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate.

(c) Within 30 months after the effective date of this AD, modify the seat tracks, in accordance with Airbus Service Bulletin A320-53-1088, Revision 3, dated March 27, 1994. Accomplishment of this modification constitutes terminating action for the requirements of this AD.

NOTE 3: Modification of the seat tracks prior to the effective date of this amendment in accordance with Airbus Service Bulletin A320-53-1088, original issue through Revision 2, is considered acceptable for compliance with theapplicable actions specified in this paragraph.

(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 4: 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 actions shall be done in accordance with All Operators Telex 53-01, dated August 27, 1992, or Airbus Service Bulletin A320-53-1088, Revision 3, dated March 27, 1994; as applicable. Revision 3 of Airbus Service Bulletin A320-53-1088 contains the following list of effective pages:

Page Number
Revision Level
Shown on Page
Date
Shown on Page
1, 4-6, 12, 13, 17, 29, 30, 45, 46,
53, 61, 62, 77, 78, 86, 93,
94, 102, 109, 110, 118, 125,
132, 139, 149, 153, 164
3
March 27, 1994
2, 13A, 13B, 14, 17A, 17B, 18
2
November 22, 1993
3, 8, 11, 15, 16, 19, 20, 21-28,
31-44, 47-52, 54-60, 63-76,
79-85, 87-92, 95-101, 103-108,
111-117, 119-124, 126-131,
133-138, 140-148, 150-152, 154-163
Original
May 10, 1993
7, 9, 10, 19A, 20A
1
August 16, 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 Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601Lind 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 July 24, 1995.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Airbus Model A320 series airplanes was published in the Federal Register on November 2, 1994 (59 FR 54849). That action proposed to require a one-time visual inspection to determine if a seat fitting having an x-plunger behind a z-stud is installed at the seat track joint at frame 64, and correction of discrepancies. That action also proposed to require modification of the seat tracks, which would terminate the requirement of repetitively removing or repositioning the seats whenever the cabin configuration is changed.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

One commenter supports the proposed rule.

One commenter requests that the terminating modification be optional ratherthan required, since there is no increase in safety by requiring the terminating modification. The commenter states that the only benefit of requiring the terminating modification is that operators do not have to repetitively remove or reposition the seat when the internal configuration of the airplane is changed. The FAA does not concur. The FAA has determined that long term continued operational safety will be better assured by design change to remove the source of the problem, rather than by repetitively removing or repositioning the seats and other equipment when the interior configuration of the airplane is changed. Repetitive removal/repositioning of the seats over the long term may not be providing the degree of safety assurance necessary for the transport airplane fleet. This, coupled with a better understanding of the human factors associated with numerous continual actions, has led the FAA to consider placing less emphasis on repetitively removing or repositioning the seats and more emphasis on design improvements. The modification requirement of this AD is in consonance with these considerations.

The same commenter requests that the compliance time for accomplishment of the modification be extended from the proposed 30 months to 48 months. This commenter states that such an extension will allow the modification to be accomplished during a regularly scheduled "D" check. This commenter states that it would have to special schedule its fleet of airplanes in order to accomplish the proposed modification within the proposed compliance time; this would entail considerable additional expenses and schedule disruptions. The FAA does not concur with the commenter's request to extend the compliance time. In developing an appropriate compliance time for this action, the FAA considered not only the degree of urgency associated with addressing the subject unsafe condition, but the availability of required parts and the practical aspect of installing therequired modification during affected operators' scheduled maintenance holds. The manufacturer has advised that an ample number of required parts will be available for modification of the U.S. fleet within the proposed compliance period. However, under the provisions of paragraph (d) of the final rule, the FAA may approve requests for adjustments to the compliance time if data are submitted to substantiate that such an adjustment would provide an acceptable level of safety.

The same commenter also requests clarification regarding the structural modification procedures described in Airbus Service Bulletin A320-53-1088, which is referenced in the proposal as the appropriate source of service information. The FAA concurs that clarification is necessary and provides the following specific information: That service bulletin describes two procedures (Solution 1 and Solution 2) for accomplishing the subject modification, depending on the magnitude of the gap. For a gap that is greater than 2.8 mm but less than 3.8 mm, Solution 1 involves removing the seat track couplings, adjusting the gap, and installing new couplings. For a gap that exceeds 3.8 mm, Solution 2 involves removing the couplings, seatrail beams, and cross beams; adjusting the gap; installing new couplings and a seatrail beam; and reinstalling the crossbeams. For further clarification purposes, the FAA has determined that, when referring to the subject modification, the phrase "modification of the seat tracks" is clearer than the phrase "repositioning or replacing the seat tracks." Therefore, the text of the final rule has been revised accordingly throughout.

Additionally, this commenter requests that the FAA revise paragraph (b)(2) of the proposal to require marking the discrepant seat track junctions so that they can be identified visually. This commenter states that marking the discrepant junctions would be a secondary method to ensure that the aft attach point of an installed article is not installed at frame 64 after accomplishing the one-time inspection. This commenter notes that it has painted discrepant junctions with red paint. The FAA does not concur totally. Neither the referenced All Operators Telex 53-01 nor Airbus Service Bulletin A320-53-1088 contain any specific procedures for marking discrepant seat track junctions. However, operators are always permitted to perform actions beyond those strictly required by an AD. Therefore, if an operator elects to mark the discrepant junctions, in addition to removing/repositioning the seat or modifying the seat tracks, it is that operator's prerogative to do so. The FAA finds it appropriate not to revise the final rule, but to leave it to the individual operators' discretion whether or not to mark the discrepant junctions.

Further, this commenter requests that the FAA ensure that the proposed rule does not reference Airbus Service Bulletin A32-53-1088 as the appropriate source of service information for removing or repositioning the seat, if the seat track junction exceeds the given valve. The commenter states that Airbus All Operators Telex 53-01 is the appropriate source of service information for these procedures. The FAA points out that the relevant paragraph (b)(2)(i)(A) of the final rule does not mention Service Bulletin A32-53-1088, and it does reference All Operators Telex 53-01.

Since issuance of the NPRM, Airbus has issued Revision 3 of Service Bulletin A320-53-1088, dated March 27, 1994. This service bulletin is essentially identical to the original issue, but contains certain editorial changes. The Direction G n rale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, has classified this service bulletin as mandatory in order to assure the continued airworthiness of these airplanes in France. The FAA has revised the final rule to reference this revision of the service bulletin as the appropriate source of service information. (Required actionsthat were previously performed in accordance with earlier revisions of this same service bulletin will be considered to be in compliance with this AD.)

As a result of recent communications with the Air Transport Association (ATA) of America, the FAA has learned that, in general, some operators may misunderstand the legal effect of AD's on airplanes that are identified in the applicability provision of the AD, but that have been altered or repaired in the area addressed by the AD. The FAA points out that all airplanes identified in the applicability provision of an AD are legally subject to the AD. If an airplane has been altered or repaired in the affected area in such a way as to affect compliance with the AD, the owner or operator is required to obtain FAA approval for an alternative method of compliance with the AD, in accordance with the paragraph of each AD that provides for such approvals. A note has been added to this final rule to clarify this long-standing requirement.Additionally, the FAA has recently reviewed the figures it has used over the past several years in calculating the economic impact of AD activity. In order to account for various inflationary costs in the airline industry, the FAA has determined that it is necessary to increase the labor rate used in these calculations from $55 per work hour to $60 per work hour. The economic impact information, below, has been revised to reflect this increase in the specified hourly labor rate.

After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes previously described. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

The FAA estimates that 85 airplanes of U.S. registry will be affected by this AD.

It will take approximately 7 work hours per airplane to accomplishthe required inspection at an average labor rate is $60 per work hour. Based on these figures, the total cost impact of the inspection required by this AD on U.S. operators is estimated to be $35,700, or $420 per airplane.

It will take approximately 54 work hours per airplane to accomplish the required modification at an average labor rate of $60 per work hour. Required parts will be supplied by the manufacturer at no cost to the operators. Based on these figures, the total impact of the modification required by this AD on U.S. operators is estimated to be $275,400, or $3,240.

Based on above figures, the total cost impact of the required inspection and modification on U.S. operators is estimated to be $311,100, or $3,660 per airplane.

The total cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

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 the Rules 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. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89.
39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: