AD 86-15-10 R2

This amendment revises an existing airworthiness directive (AD), applicable to Eurocopter France Model AS-350B, BA, B1, B2, C, D, and D1, and AS-355E, F, F1, F2 and N helicopters, that currently requires repetitive inspections of the main rotor head components, the main gearbox (MGB) suspension bars, and the ground resonance prevention system components at intervals not to exceed 400 hours time-in-service (TIS). This amendment requires the same inspections, but at intervals not to exceed 500 hours TIS. This amendment is prompted by reports of confusion and unnecessary costs associated with the difference in the current 400 hours TIS inspection interval and the current manufacturer's master service recommendation of 500 hours TIS inspection interval. The actions specified by this AD are intended to eliminate confusion and unnecessary costs and to prevent ground resonance due to reduced structural stiffness, which could lead to failure of a main rotor head or MGB suspensioncomponent and subsequent loss of control of the helicopter.

Final rule

86-15-10 R2 EUROCOPTER FRANCE: Amendment 39-11681. Docket No. 98-SW-82-AD. Revises AD 86-15-10, Amendment 39-5517 and AD 86-15-10 R1, Amendment 39-6515.
Applicability: Model AS-350B, BA, B1, B2, C, D, and D1, and AS-355E, F, F1, F2 helicopters, 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 (f) 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: Required as indicated, unless accomplished previously.

To prevent ground resonance due to reduced structural stiffness, which could lead to failure of a main rotor head or main gearbox (MBG) suspension component and subsequent loss of control of the helicopter, accomplish the following:

(a) Within 10 hours time-in-service (TIS):

(1) For Model AS-350B, BA, B1, B2, C, D, and D1 helicopters, inspect the main rotor head components, the MGB suspension bars (struts), and the landing gear ground resonance prevention components (aft spring blades and hydraulic shock absorbers) in accordance with paragraph CC.3 of Aerospatiale Service Bulletin (SB) No. 01.17a (not dated).

(2) For Model AS-355E, F, F1, F2 helicopters, inspect the main rotor head components, the MGB suspension bars (struts), and the landing gear ground resonance prevention components (aft spring blades and hydraulic shock absorbers) in accordance with paragraph CC.3 of SB No. 01.14a (not dated).

(b) Rework or replace damaged components in accordance with SB No. 01.17a or SB No. 01.14a, as applicable.

(c) Repeat the inspections and rework required by paragraphs (a) and (b) of this AD at intervals not to exceed 500 hours TIS.

(d) If the helicopter is subjected to a hard landing or to high surface winds, when parked without effective tiedown straps installed, repeat the inspections required by paragraph (a) of this AD for the main rotor head star arms and the MGB suspension bars before further flight.

(e) In the event of a landing which exhibits abnormal self-sustained dynamic vibrations (ground resonance type vibrations), repeat all the inspections contained in paragraph (a) of this AD.

(f) 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, FAA, Regulations Group, 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 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group.

(g) Special flight permits may be issued in accordance with sections 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.

(h) The inspections and modification shall be done in accordance with Aerospatiale Service Bulletin No. 01.17a or No. 01.14a (neither is dated). This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from American Eurocopter Corporation, 2701 Forum Drive, Grand Prairie, Texas 75053-4005, telephone (972) 641-3460, fax (972) 641-3527. Copies may be inspected at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(i) This amendment becomes effective on May 23, 2000.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by revising AD 86-15-10, Amendment 39-5517 (52 FR 13233, April 22, 1987) and AD 86-15-10 R1, Amendment 39-6515 (55 FR 5833, February 20, 1990), which is applicable to Eurocopter France Model AS-350B, BA, B1, B2, C, D, and D1, and AS-355E, F, F1, F2 and N helicopters, was published in the Federal Register on January 20, 2000 (65 FR 3165). The action proposed to require repetitive inspections of the main rotor head components, the MGB suspension bars, and the ground resonance prevention system components at intervals not to exceed 500 hours TIS.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

The FAA has determined that this regulation is relieving in nature and imposes no additional costs or regulatory burden on any person.

The regulations adopted herein will 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 final rule does not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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 removing Amendment 39-5517 (52 FR 13233, April 22, 1987) and Amendment 39-6515 (55 FR 5833, February 20, 1990) and by adding a new airworthiness directive (AD), Amendment 39-11681, to read as follows: