Airworthiness Directives; Eurocopter France Model SA-365C, C1, C2, N, and N1; AS-365N2 and N3; and SA-366G1 Helicopters

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of an existing airworthiness directive (AD) applicable to Eurocopter France Model SA-365C, C1, C2, N, and N1; AS-365N2, and SA-366G1 helicopters. This proposal contains the same requirements as the existing AD but would add the Model AS-365N3 helicopter to the applicability. This proposal would require inspecting the tightening torque of the main rotor hub blade attach beam spherical thrust bearing bolts (bolts) and either applying a specified torque or, if necessary, inspecting for a crack in the metal components. This proposal would also require replacing the spherical thrust bearing (bearing) with an airworthy bearing if a crack is found. This proposal is prompted by reports of cracks in the metal components of the bearing attachment joint and the need to add the Eurocopter France Model AS 365 N3 helicopter to the applicability. The actions specified by the proposed AD are intended to prevent loosening of bearing bolts in flight, which may cause cracks in the metal components, failure of the bearing, and subsequent loss of control of the helicopter.

DATES:

Comments must be received on or before May 1, 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-62-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. Comments may be inspected at this location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal holidays.

The service information referenced in the proposed rule may be obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-3527. This information may be examined at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas.

FOR FURTHER INFORMATION CONTACT:

Shep Blackman, Aerospace Engineer, FAA, Rotorcraft Directorate, Regulations Group, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5296, fax (817) 222-5961.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed 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 above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket No. 99-SW-62-AD.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 99-SW-62-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Discussion

On October 5, 1999, the FAA issued AD 99-21-24, Amendment 39-11369 (64 FR 55621), applicable to Eurocopter France Model SA-365C, C1, C2, N, and N1; AS-365N2; and SA-366G1 helicopters, to require inspecting the tightening torque of the bolts and either applying a specified torque or, if necessary, dye-penetrant inspecting for a crack in the metal components, and replacing any unairworthy bearing with an airworthy bearing. That action was prompted by reports of cracks in the metal components of the bearing attachment joint. The requirements of that AD were intended to prevent failure of the bearing and subsequent loss of control of the helicopter.

Since the issuance of that AD, the FAA has discovered the inadvertent omission in the applicability of the Eurocopter France Model AS-365N3 helicopter. This proposal would add the Model AS 365 N3 helicopter.

Since an unsafe condition has been identified that is likely to exist or develop on other Eurocopter France Model SA-365C, C1, C2, N, and N1; AS-365N2 and N3; and SA-366G1 helicopters of the same type design, the proposed AD would supersede AD 99-21-24 but would contain the same requirements as AD 99-21-24 with the addition of the Eurocopter France Model AS-365N3 to the applicability.

The FAA estimates that 101 helicopters of U.S. registry would be affected by this proposed AD, that it would take approximately 0.5 work hour per helicopter and approximately 3,000 inspections per helicopter over the life of the fleet to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Required parts would cost approximately $3,000 per helicopter. Based on these figures, the total cost impact of the proposed AD on U.S. operators is estimated to be $9,123,000, assuming 11 ship sets of bearings would need to be replaced on the fleet.

The regulations proposed herein would 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 among the various levels of government. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) Is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting 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

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.