Airworthiness Directives; Eurocopter France Model AS-350B, BA, B1, B2, and D, and Model AS-355E, F, F1, F2, and N 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 AS-350B, BA, B1, B2, and D, and Model AS-355E, F, F1, F2, and N helicopters, that currently requires inspecting the main gearbox suspension bi-directional cross-beam (cross-beam) for cracks, and replacing the cross-beam if a crack is found. This action would require the same inspections as the existing AD but would add the time intervals for performing repetitive dye-penetrant inspections on cross-beams with 5,000 or more hours time-in-service (TIS). This proposal is prompted by the discovery that time intervals for performing the required dye-penetrant inspections are not included in the existing AD. The actions specified by the proposed AD are intended to prevent failure of the cross-beam that could cause the main gearbox to pivot resulting in severe vibrations and a subsequent forced landing.

DATES:

Comments must be received on or before April 11, 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-39-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:

Jim Grigg, Aerospace Engineer, FAA, Rotorcraft Directorate, ASW-111, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5490, 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-39-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-39-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Discussion

On June 19, 1998, the FAA issued AD 98-14-01, Amendment 39-10635 (63 FR 35128, June 29, 1998), to require visual and dye-penetrant inspections of the cross-beam for cracks and replacement with an airworthy cross-beam if a crack is found. That action was prompted by several reports of cracks in the cross-beam. The requirements of that AD are intended to provide a terminating action to prevent failure of the cross-beam that could cause the main gearbox to pivot resulting in severe vibrations and a subsequent forced landing.

Since the issuance of that AD, the FAA has discovered that the time intervals for performing the required repetitive dye-penetrant inspections on cross-beams with 5,000 or more hours TIS were not included. The initial dye-penetrant inspection for cracks must be performed when the cross-beams attain 5,000 hours TIS or 2,750 cycles, whichever occurs first. Thereafter, repetitive dye-penetrant inspections for cracks must be performed at intervals not to exceed 550 hours TIS or 2,750 operating cycles, whichever occurs first.

Since an unsafe condition has been identified that is likely to exist or develop on other Eurocopter France Model AS-350B, BA, B1, B2, and D, and Model AS-355E, F, F1, F2, and N helicopters of the same type design, the proposed AD would supersede AD 98-14-01 to require, at specified time intervals or cycles, repetitive visual and dye-penetrant inspections of the cross-beam for cracks, and replacing, if necessary, the cross-beam with an airworthy cross-beam.

The FAA estimates that 454 helicopters of U.S. registry would be affected by this proposed AD; that it would take approximately 0.5 work hour per helicopter to accomplish each visual inspection, with an estimated average of 150 visual inspections per helicopter, 3 work hours per helicopter to accomplish a dye-penetrant inspection, with an estimated average of 3 dye-penetrant inspections per helicopter, and 6 work hours per helicopter to replace the cross-beam, if necessary; and that the average labor rate is $60 per work hour. Parts would cost approximately $6,000 per cross-beam. Based on these figures, the total cost impact of the proposed AD on U.S. operators is estimated to be $5,175,600 to perform 150 visual inspections and an average of 3 dye-penetrant inspections per helicopter and to replace the cross-beam on all 454 helicopters.

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 and responsibilities 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.