AD 2004-07-02

This amendment adopts a new airworthiness directive (AD) that is applicable to all Airbus Model A318, A319, A320, and A321 series airplanes. This action requires a one-time general visual inspection to determine the part number and serial number of both main landing gear (MLG) sliding tubes, and related investigative and corrective actions if necessary. This action is necessary to detect and correct cracking in a MLG sliding tube, which could result in failure of the sliding tube, loss of one axle, and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

Final rule; request for comments.

2004-07-02 Airbus: Amendment 39-13546. Docket 2004-NM-43-AD.

Applicability: All Model A318, A319, A320, and A321 series airplanes, certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To detect and correct cracking in a main landing gear (MLG) sliding tube, which could result in failure of the sliding tube, loss of one axle, and consequent reduced controllability of the airplane, accomplish the following:

Part Number Identification, Detailed Inspection, and Corrective Action

(a) Within 30 days after the effective date of this AD: Do a one-time general visual inspection to determine the part number (P/ N) and serial number (S/N) of both MLG sliding tubes, per Airbus All Operators Telex (AOT) A320-32A1273, dated February 5, 2004.

(1) If both the P/N and S/N of any MLG sliding tube are not listed in the AOT: No further action is required by this paragraph for that MLG sliding tube.

(2) If both the P/N and S/Nof any MLG sliding tube are listed in the AOT: Before further flight, do a detailed inspection of the MLG sliding tube for cracking, per the AOT.

(i) If no cracking is found in any MLG sliding tube: Repeat the detailed inspection thereafter at intervals not to exceed 10 days.

(ii) If any cracking is found in any MLG sliding tube: Before further flight, replace the part with a new or serviceable part per a method approved by either the FAA or the Direction Generale de l'Aviation Civile (or its delegated agent). Chapter 32 of the Airbus A318/A319/A320/A321 Aircraft Maintenance Manual is one approved method. Installation of a MLG sliding tube that does not have both a P/N and a S/N listed in Airbus AOT A320-32A1273, dated February 5, 2004, is terminating action for the repetitive inspections required by paragraph (a)(2)(i) of this AD for that MLG sliding tube only.

Note 1: For the purposes of this AD, a general visual inspection is defined as: "A visual examination of an interior or exterior area, installation, or assembly to detect obvious damage, failure, or irregularity. This level of inspection is made from within touching distance unless otherwise specified. A mirror may be necessary to enhance visual access to all exposed surfaces in the inspection area. This level of inspection is made under normally available lighting conditions such as daylight, hangar lighting, flashlight, or droplight and may require removal or opening of access panels or doors. Stands, ladders, or platforms may be required to gain proximity to the area being checked."

Note 2: For the purposes of this AD, a detailed inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required."

Submission of Cracked Parts Not Required

(b) The AOT specifies to send any cracked part to Messier-Dowty. This AD does not include such a requirement.

Reporting Requirement

(c) Submit a report of any positive findings of cracking found during any detailed inspection required by paragraph (a)(2)(i) of this AD to Airbus Customer Services, Engineering and Technical Support, Attention: M.Y. Quimiou, SEE33, fax +33+ (0) 5.6193.32.73, at the applicable time specified in paragraph (c)(1) or (c)(2) of this AD. The report must include the MLG P/N and S/N, date of inspection, a description of any cracking found, the airplane serial number, and the number of flight cycles on the MLG at the time of inspection. Under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has approved the information collection requirements contained in thisAD and has assigned OMB Control Number 2120-0056.

(1) If the inspection is done after the effective date of this AD: Submit the report within 30 days after the inspection.
(2) If the inspection was done prior to the effective date of this AD: Submit the report within 30 days after the effective date of this AD.

Parts Installation

(d) As of the effective date of this AD, no person may install a MLG sliding tube having both a P/N and S/N specified in Airbus AOT A320-32A1273, dated February 5, 2004, on any airplane, unless the part has been inspected, and any applicable correction accomplished, per paragraph (a) of this AD.

Alternative Methods of Compliance

(e) In accordance with 14 CFR 39.19, the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, is authorized to approve alternative methods of compliance for this AD.

Incorporation by Reference

(f) Unless otherwise specified in this AD, the actions shall be done in accordance with Airbus All Operators Telex A320-32A1273, dated February 5, 2004. (The manufacturer, date, and document number of the All Operators Telex only appear on page 1 of the document.) 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, 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.

Note 3: The subject of this AD is addressed in French airworthiness directive F-2004-022, dated February 18, 2004.

(g) This amendment becomes effective on April 14, 2004.

The Direction Generale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, notified the FAA that an unsafe condition may exist on all Airbus Model A318, A319, A320, and A321 series airplanes. The DGAC advises that during a routine visual inspection of a main landing gear (MLG) sliding tube, a linear crack was found at the intersection of the cylinder and the axle. Investigation revealed that the crack was caused by non-metallic inclusions in the base metal. A specific batch of MLG sliding tubes that may have these inclusions has been identified. Such cracking, if not corrected, could result in failure of the affected MLG sliding tube, loss of one axle, and consequent reduced controllability of the airplane.

Explanation of Relevant Service Information

Airbus has issued All Operators Telex (AOT) 320-32A1273, dated February 5, 2004, which describes procedures for identifying the part number (P/N) and (S/N) of both MLG sliding tubes. The procedures for the P/N and S/N identification include visually inspecting ("checking") and cleaning the part number plate, and reporting the S/ N to Airbus. For airplanes on which the S/N is included in the batch of affected S/Ns listed in the AOT, the procedures include:
Cleaning the visible part of the MLG sliding tube and visually inspecting the part for surface cracking.
Removing any MLG sliding tube with cracking from the airplane, reporting the cracking to Airbus, and sending the affected part to Messier-Dowty.
Repeating the inspection for cracking at intervals not exceeding 10 days, until a final fix is found.

The DGAC classified this AOT as mandatory and issued French airworthiness directive F-2004-022, dated February 18, 2004, to ensure the continued airworthiness of these airplanes in France.

FAA's Conclusions

These airplane models are manufactured in France and are 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 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 detect and correct cracking in a MLG sliding tube, which could result in failure of the sliding tube, loss of one axle, and consequent reduced controllability of the airplane. This AD requires a one-time general visual inspection to determine the P/N and S/N of both MLG sliding tubes, and related investigative and corrective actions if necessary. The related investigative actions include repetitive detailed inspections for cracking of the MLG sliding tubes. The corrective actions include replacement of a cracked part with a new or serviceable part. Installation of a replacement part that does not have a S/N as listed in Airbus AOT A320-32A1273 eliminates the need for the repetitive inspections for only that part.

The actions are required to be accomplished in accordance with the AOT described previously, except as discussed below under "Differences Among the French Airworthiness Directive, Service Information, and This AD."

This AD also includes a reporting requirement. When the unsafe condition addressed by an AD is likely due to a manufacturer's quality control (QC) problem, a reporting requirement is instrumental in ensuring that we can gather as much information as possible regarding the extent and nature of the QC problem or breakdown, especially in cases where such data may not beavailable through other established means. This information is necessary to ensure that proper corrective action will be taken.

Differences Among the French Airworthiness Directive, Service Information, and This AD

The applicability of the French airworthiness directive does not include Airbus Model A318 series airplanes, but the effectivity of the AOT does include that model. The applicability of this AD includes the Airbus Model A318 series airplanes to ensure that all airplanes that might have an affected MLG sliding tube are inspected and any necessary corrective actions taken.

Also, the applicability of the French airworthiness directive and the effectivity of the AOT include P/Ns and the list of affected S/Ns for the MLG sliding tubes. The applicability of this AD does not include any P/Ns or S/Ns. We find that listing the P/Ns and S/Ns in the applicability is not necessary because paragraph (a) of this AD requires a general visual inspection to determine the P/N and S/N of both MLG sliding tubes.

The AOT specifies to send any cracked part to Messier-Dowty. This AD does not include such a requirement.

Clarification of Inspection Terminology

The Airbus AOT specifies to "visually check" the serial number displayed on the MLG sliding tube. This AD requires a general visual inspection, which is defined in Note 1 of this AD. For certain airplanes, the AOT also specifies to "visually check" the MLG sliding tube for surface cracking. This AD requires a detailed visual inspection, which is defined in Note 2 of this AD.

Clarification of Corrective Action

The Airbus AOT specifies to remove any cracked MLG sliding tube from the airplane, but does not specify to replace the affected part with another part. This AD requires the replacement of any cracked part with a new or serviceable part.

Interim Action

We consider this AD to be interim action. The manufacturer is currently developing a non-destructive inspection technique todetect non-metallic inclusions in the base metal of the MLG sliding tube, which, along with any necessary corrective actions, will address the unsafe condition identified in this AD. Once this inspection is developed, approved, and available, we may consider additional rulemaking.

Determination of Rule's Effective Date

Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an 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.

Submit comments using the following format:

Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
For each issue, state what specific change to the AD is being requested.
Include justification (e.g., reasons or data) for each request.

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 2004-NM-43-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Impact

The regulations adopted herein will not have a substantial direct effect 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, it is determined that this final rule does not have federalism implications under Executive Order 13132.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, 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: