[Federal Register Volume 64, Number 243 (Monday, December 20, 1999)] [Rules and Regulations] [Pages 71012-71014] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 99-32735] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION Federal Aviation Administration 14 CFR Part 39 [Docket No. 99-SW-63-AD; Amendment 39-11474; AD 99-26-14] RIN 2120-AA64 Airworthiness Directives; Agusta S.p.A. Model AB412 Helicopters AGENCY: Federal Aviation Administration, DOT. ACTION: Final rule; request for comments. ----------------------------------------------------------------------- SUMMARY: This amendment adopts a new airworthiness directive (AD) applicable to Agusta S.p.A. Model AB412 helicopters. This action requires removing and replacing certain main rotor yokes with airworthy main rotor yokes before further flight. This amendment is prompted by the fatigue failure of a main rotor yoke (yoke). Fatigue analysis indicates that certain yokes are on the low end of the manufacturer's tolerance for thickness and do not have the desired margin of safety. This condition, if not corrected, could result in fatigue failure of the yoke, loss of a main rotor blade, and subsequent loss of control of the helicopter. DATES: Effective January 4, 2000. Comments for inclusion in the Rules Docket must be received on or before February 18, 2000. ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 99-SW-63-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. The service information referenced in this AD may be obtained from Agusta, 21017 Cascina Costa di Samarate (VA), Via Giovanni Agusta 520, telephone (0331) 229111, fax (0331) 229605-222595. This information may be examined at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. FOR FURTHER INFORMATION CONTACT: Shep Blackman, Aerospace Engineer, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5296, fax (817) 222-5961. SUPPLEMENTARY INFORMATION: The Registro Aeronautico Italiano (RAI), the airworthiness authority for Italy, notified the FAA that an unsafe condition may exist on Agusta S.p.A. Model AB412 helicopters. The RAI advises removing and replacing the yoke, part number (P/N) 412-010-101- 123 or -127, with an airworthy yoke, P/N 412-010-101-129. Agusta S.p.A. has issued Alert Bollettino Tecnico 412-74, dated March 16, 1999, (technical bulletin) which specifies reducing the retirement life of the yoke, P/N 412-010-101-123 and -127, from 5000 hours to 4500 hours time-in-service (TIS), and replacing a yoke having 4500 or more hours TIS with an airworthy yoke, P/N 412-010-101-129, which has a retirement life of [[Page 71013]] 5000 hours. The RAI classified this technical bulletin as mandatory and issued AD 99-179, dated April 16, 1999, to require replacing the yoke, P/N 412-010-101-123 or -127, with an airworthy yoke, P/N 412-010-101- 129, before further flight, 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. Since an unsafe condition has been identified that is likely to exist or develop on other Agusta S.p.A. Model AB412 helicopters of the same type design registered in the United States, this AD is being issued to prevent fatigue failure of the yoke, loss of a main rotor blade, and subsequent loss of control of the helicopter. This AD requires removing and replacing a yoke, P/N 412-010-101-123 or -127, with an airworthy yoke, P/N 412-010-101-129, before further flight. The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the structural integrity and controllability of the helicopter. Therefore, removing and replacing certain unairworthy yokes with airworthy yokes is required prior to further flight and this AD must be issued immediately. None of the Agusta S.p.A. Model AB412 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 60 work hours to replace the yoke, at an average labor rate of $60 per work hour. Required parts would cost $89,742 per helicopter. Based on these figures, the cost impact of this AD would be $93,342 per helicopter. 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. 99-SW-63-AD.'' The postcard will be date stamped and returned to the commenter. The regulations adopted herein will not impose substantial direct compliance costs on states or local governments or 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 13132, the FAA has not consulted with States or local authorities prior to the publication of this rule. The FAA has determined no U.S. registered helicopters are affected by this regulation 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, 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 a new airworthiness directive to read as follows: AD 99-26-14 AGUSTA S.p.A.: Amendment 39-11474. Docket No. 99-SW-63- AD. Applicability: Model AB412 helicopters, with main rotor yoke, part number (P/N) 412-010-101-123 or -127, installed, certificated in any category. Note 1: This AD applies to each helicopter 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 helicopters 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 (b) 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: Before further flight, unless accomplished previously. [[Page 71014]] To prevent fatigue failure of a main rotor yoke (yoke), loss of a main rotor blade, and subsequent loss of control of the helicopter, accomplish the following: (a) Remove and replace each yoke, P/N 412-010-101-123 or -127, with an airworthy yoke, P/N 412-010-101-129. Note 2: Agusta S.p.A. Bollettino Tecnico 412-74, dated March 16, 1999, pertains to the subject of this AD. (b) 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, Regulations Group, FAA, Rotorcraft Directorate. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Regulations Group. Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group. (c) Special flight permits may be issued in accordance with Sec. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the helicopter to a location where the requirements of this AD can be accomplished. (d) This amendment becomes effective on January 4, 2000. Note 4: The subject of this AD is addressed in Registro Aeronautico Italiano (Italy) AD 99-179, dated April 16, 1999. Issued in Fort Worth, Texas, on December 10, 1999. Larry M. Kelly, Acting Manager, Rotorcraft Directorate, Aircraft Certification Service. [FR Doc. 99-32735 Filed 12-17-99; 8:45 am] BILLING CODE 4910-13-U