The Registro Aeronautico Italiano (RAI), which is the airworthiness authority for Italy, recently notified the FAA that an unsafe condition may exist on Agusta Model AB 412 helicopters with tail rotor blades, part number (P/N) 212-010-750-105, serial number A5-(all numbers). The RAI advises that debond voids can result in loss of the tip cap closure block, P/N 209-010-719-3, from the blade, causing a severely out-of-balance tail rotor assembly, increased helicopter vibration levels, damage to the tail rotor drive system or tail rotor assembly, and subsequent loss of control of the helicopter.
Agusta has issued Agusta Bollettino Tecnico (Technical Bulletin) No. 412-66, dated June 27, 1997, which specifies an inspection of the tail rotor blades for debond voids between the tip cap and blade spar/skin. The RAI classified this Technical Bulletin as mandatory and issued AD 97-194, dated July 9, 1997, in order to assure the continued airworthiness of these helicopters in Italy.
This helicopter model is manufactured in Italy 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 RAI has kept the FAA informed of the situation described above. The FAA has examined the findings of the RAI, 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.
This AD is being issued to prevent increased vibration levels, damage to the tail rotor drive system or tail rotor assembly, and subsequent loss of control of the helicopter. This AD requires an inspection of the tail rotor blades for debond voids and replacement, if necessary. The actions are required to be accomplished in accordance with the technical bulletin described previously.
None of the Agusta Model AB 412 helicopters affected by this action are on the U.S. Register. All helicopters included in the applicability of this rule currently are operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, the FAA considers that this rule is necessary to ensure that the unsafe condition is addressed in the event that any of these subject helicopters are imported and placed on the U.S. Register in the future.
Should an affected helicopter be imported and placed on the U.S. register in the future, it would require approximately 1 work hour per helicopter for the inspection and 4 work hours for the replacement, if necessary, of a tail rotor blade. The average labor rate is $60 per work hour. Required blades, if needed, would cost $7,922 per blade. Based on these figures, the cost impact of this AD, should a helicopter be placed on the U.S. Register, wouldbe $8,222 per helicopter, assuming an inspection and replacement of a tail rotor blade are accomplished.
Since this AD action does not affect any helicopter that is currently on the U.S. register, it has no adverse economic impact and imposes no additional burden on any person. Therefore, notice and public procedures hereon are unnecessary and the amendment may be made effective in less than 30 days after publication in the Federal Register.
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-63-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 notice and prior public comment are unnecessary in promulgating this regulation and therefore, it can be issued immediately to correct an unsafe condition in aircraft since none of these model helicopters are registered in the United States, 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: