Airworthiness Directives; Airbus Model A330 and A340 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

This amendment adopts a new airworthiness directive (AD) that is applicable to certain Airbus Model A330 and A340 series airplanes. This action requires repetitive inspections to detect discrepancies of the transfer tubes and the collar of the ball nut of the trimmable horizontal stabilizer actuator (THSA); and corrective action, if necessary. This action is necessary to prevent degraded operation of the THSA due to the entrance of water into the ball nut. Degraded operation could lead to reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Effective June 26, 2001.

The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of June 26, 2001.

Comments for inclusion in the Rules Docket must be received on or before July 11, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-135-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. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: 9-anm-iarcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-135-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 for Windows or ASCII text.

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.

FOR FURTHER INFORMATION CONTACT:

Dan Rodina, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2125; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

The Direction Générale 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 A330 and A340 series airplanes. The DGAC advises that four cases of transfer tube disconnection from the ball nut of the trimmable horizontal stabilizer actuator (THSA) have been detected during greasing of in-service Model A330 and A340 series airplanes. The cause was found to be water entering the ball nut of the THSA, resulting in jamming of the ball transfer path when the water froze. There are three independent circuits of balls. The loss of one or two circuits does not impact the THSA operation, as it continues to operate on the remaining circuits. If three circuits are lost, then the THSA operates on the fail-safe nut. Due to the high friction between the fail-safe nut and the screw, THSA operation will be inefficient and it will lock after a few movements. This degraded operation is not detectable by the flight crew as long as the THSA is not locked and could damage the screw and the fail-safe nut. Jamming of the ball transfer paths, if not corrected, could result in degraded operation of the THSA and consequent reduced controllability of the airplane.

Explanation of Relevant Service Information

Airbus has issued All Operator Telexes (AOT) A330-27A3088 and A340-27A4093, both dated April 5, 2001, which describe procedures for repetitive detailed visual inspections of the ball nut in the area of the transfer tubes for, among other things, evidence of ball migration from the ball nut; distortion of the collar or transfer tubes; or disconnection of the transfer tubes from the ball nut; and replacement of the THSA, if necessary. The DGAC classified these AOTs as mandatory and issued French airworthiness directives 2001-141(B) and 2001-140(B), both dated April 18, 2001, in order to assure the continued airworthiness of these airplanes in finance.

FAA's Conclusions

These airplane models are manufactured in and are type certificated for operation in the United States under the provisions of § 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 prevent degraded operation of the THSA due to the entrance of water into the ball nut, and consequent reduced controllability of the airplane. This AD requires accomplishment of the actions specified in the applicable AOT described previously. This AD also requires that operators report results of inspection findings to Airbus.

Interim Action

This is considered to be interim action until final action is identified, at which time the FAA may consider further 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 2001-NM-135-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.

2. Section 39.13 is amended by adding the following new airworthiness directive:

2001-11-09  Airbus Industrie: Amendment 39-12252. Docket 2001-NM-135-AD.

Applicability: Model A330 and A340 series airplanes, certificated in any category, equipped with a trimmable horizontal stabilizer actuator (THSA) part number 47172, and on which Airbus Modification 45299 has been performed.

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 (d) 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 the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent degraded operation of the THSA due to the entrance of water into the ball nut, and consequent reduced controllability of the airplane, accomplish the following:

Repetitive Inspections

(a) Within 150 flight hours from the effective date of this AD, perform a detailed visual inspection to detect discrepancies in the THSA (including distortion of the transfer tubes, disconnection of the tubes, and distortion of the collar of the ball nut), in accordance with All Operators Telex (AOT) A330-27A3088 (for Model A330 series airplanes) or A340-27A4093 (for Model A340 series airplanes), both dated April 5, 2001, as applicable. If any discrepancy, as defined in paragraph 4-2-2/Rejection Criteria of the applicable AOT, is detected, prior to further flight, replace the THSA with a serviceable one, per the applicable AOT.

Note 2:

For the purposes of this AD, a detailed visual 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.”

(b) At intervals not to exceed 150 flight hours, repeat the inspection mandated in paragraph (a) of this AD.

Report of Inspection Findings

(c) Submit a report of inspection findings (both positive and negative) to Airbus; at the applicable time specified in paragraph (c)(1) or (c)(2) of this AD. The report must include the inspection results, a description of any discrepancies found, the airplane serial number, and the number of landings and flight hours on the airplane. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

(1) For airplanes on which the inspection is accomplished after the effective date of this AD: Submit the report within 10 days after performing the inspection required by paragraph (a) or (b) of this AD.

(2) For airplanes on which the inspection has been accomplished prior to the effective date of this AD: Submit the report within 10 days after the effective date of this AD.

Alternative Methods of Compliance

(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, International Branch, ANM-116, Transport Airplane Directorate, FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116.

Note 3:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

Special Flight Permits

(e) Special flight permits may be issued in accordance with §§ 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.

Incorporation by Reference

(f) The inspections and replacement shall be done in accordance with Airbus All Operators Telex A330-27A3088, dated April 5, 2001; or Airbus All Operators Telex A340-27A4093, dated April 5, 2001; as applicable. 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.

Note 4:

The subject of this AD is addressed in French airworthiness directives 2001-141(B) and 2001-140(B), both dated April 18, 2001.

Effective Date

(g) This amendment becomes effective on June 26, 2001.