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 A300 B2 and B4 series airplanes. The DGAC advises that two reports were received which indicated that, during regularly scheduled maintenance, damage to the variable lever arm (VLA) of the rudder control system was found. Further investigation revealed that the VLA spring box mountings, the mounting trunnion, and a tie rod also were damaged. Such damage was attributed to corrosion of the spring boxes. Both affected spring boxes were installed per the pre-vendor service bulletin (VSB) 27-21-1H standard, causing stiff operation of the springs and subsequent damage. Failure of one spring box of the VLA does not affect safety of flight, but failure of both spring boxes could result in loss of rudder control and consequent reduced controllability of the airplane.
Explanation ofRelevant Service Information
Airbus has issued All Operators Telex (AOT) A300-27A0196, dated September 20, 2001, which describes procedures for determining the part and amendment numbers of the variable lever arm (VLA) of the rudder control system to verify the spring boxes were installed using the post-VSB 27-21-1H standard, and corrective actions, if necessary. The corrective actions include a detailed visual inspection of the VLA tie rod for damage (bent or ruptured rod) if the part and amendment numbers of the VLA are incorrect, and replacement of any damaged tie rod with a new tie rod.
The DGAC classified this AOT as mandatory and issued French telegraphic airworthiness directive T 2001-447(B), dated September 24, 2001, in order to assure 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 ofthe 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 failure of both spring boxes of the variable lever arm (VLA) due to corrosion damage, which could result in jammed rudder pedals, loss of rudder control, and consequent reduced controllability of the airplane. This AD requires a one-time inspection to determine the part number of the VLA of the rudder control system, andfollow-on actions, if necessary. The actions are required to be accomplished in accordance with the AOT described previously.
Interim Action
This is considered to be interim action. The manufacturer is gathering data that will enable it to obtain better insight into the nature, cause, and extent of the corrosion damage, and eventually to develop final action to address the unsafe condition. Once final action has been identified, 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-300-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.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: