The Civil Aviation Authority (CAA), which is the airworthiness authority for the United Kingdom (UK), recently notified the FAA that an unsafe condition may exist on Westland 30 series helicopters. The UK CAA advises that two incidents of drive shaft attachment flange cracking occurred on the Lynx model helicopters, the UK military version of the Westland 30 helicopters. Consequently, the appropriate drive shaft lives for the Westland 30 series helicopters have been reconsidered.
Westland has issued GKN Westland Helicopters Ltd. Service Bulletin (SB) Nos. W30-65-48, dated November 29, 1995, and W30-65-48, Annex A, dated November 8, 1996, which specify the procedure to establish the current TIS of the Westland 30 series helicopters drive shafts, the hours at which the drive shafts should be replaced or inspected, and the inspection procedure. The UK CAA classified these SB s as mandatory and issued UK CAA AD 013-11-95, dated January 31, 1996, to ensure the continued airworthiness of these helicopters in the UK.
These helicopter models, manufactured in Yeovil, England, are 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 UK CAA has kept the FAA informed of the situation described above. The FAA has examined the findings of the UK CAA, 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 Westland 30 series helicopters of the same type design eligible for registration in the United States, this AD is being issued to prevent failure of the drive shaft coupling attachment flanges that could result in loss of power to the tail rotor and the subsequent loss of control of the helicopter. This AD requires that the TIS of each of the six drive shafts be determined from the helicopter records and that a component history card or an equivalent record be created for each drive shaft. If drive shaft No. 1, 2, 3, 4, or 5 exceeds 1,000 hours TIS or drive shaft No. 6 exceeds 500 hours TIS, replacement with an airworthy drive shaft in accordance with the SB is required. Alternatively, inspection of any drive shaft (No. 1, 2, 3, 4, or 5) with over 1,000 hours TIS and drive shaft No. 6 with over 500 hours TIS is required in accordance with GKN Westland Helicopters Ltd. SB No. W30-65-48, paragraph 2.B.(3), dated November 29, 1995, prior to further flight and thereafter at intervals not to exceed 3 hours TIS. The actions are required to be accomplished in accordance with the SB s previously described.
None of the Westland 30 series helicopters affected by this action are on the U.S. Register. All helicopters included in the applicability of this rule are currently operated by non-U.S. operators under foreign registry; therefore, they are not directly affected by this AD action. However, the FAA considers this rule 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, it will require approximately 2 work hours to accomplish each required inspection at an average labor rate of $60 per work hour. Based on these figures, the cost impact of this AD will be $1200 per helicopter for accomplishment of 10 drive shaft flange inspections.
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, it is found that notice and opportunity for prior public comment hereon are unnecessary, 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-26-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 public comment are unnecessary in promulgating this regulation, that the regulation 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: