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 Eurocopter France Model SA341G and SA342J helicopters. The DGAC advises that cracks have been found in the welds of the support tripod, part number 341A23-1136-00 -01, or -02, and is mandating a visual inspection, and if the results of the visual inspection are inconclusive, a dye-penetrant inspection for cracks.
Eurocopter France has issued Eurocopter SA 341/342 Service Bulletin No. 05.32, dated July 17, 1997, which specifies visual inspections, and if there is any doubt about the results of the visual inspection, a dye-penetrant inspection, for cracks on the support tripod and replacement with an airworthy support tripod if a crack is found. The DGAC classified this service bulletin as mandatory and issued AD 97-144-038(B), dated July 2, 1997, in order to assure the continued airworthiness of these helicopters in France.
This helicopter 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.
Since an unsafe condition has been identified that is likely to exist or develop on other Eurocopter France Model SA341G and SA342J helicopters of the same type design registered in the United States, this AD is being issued to detect cracks at the welds of the tail gearbox support tripod, which could cause failure of one or more of the tripod arms, separationof the tail gearbox and subsequent loss of control of the helicopter. This AD requires, before further flight, and thereafter, prior to the first flight of each day, or at intervals not to exceed 10 hours time-in-service, whichever occurs first, visual inspections of the support tripod for cracks. If the visual inspections indicate potential cracks, a dye-penetrant inspection is required. If a crack is found, replacing the support tripod with an airworthy support tripod is required. The actions are required to be accomplished in accordance with the service bulletin described previously.
The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the controllability of the helicopter. Therefore, the inspections for cracks are required prior to further flight, and this AD must be issued immediately.
The FAA estimates that 24 helicopters of U.S. registry would be affected by this AD, that it would take approximately one-half work hour to conduct the visual inspection and 9 work hours to replace the support tripod, and that the average labor rate is $60 per work hour. Required parts would cost approximately $203,304. Based on these figures, the total cost impact of this AD on U.S. operators is estimated to be $4,892,976, if the support tripod is replaced in all of the U.S. fleet.
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 should 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 No. 97-SW-51-AD." The postcard will be date stamped and returned to the commenter.
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.
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 a new airworthiness directive to read as follows: