AD 98-12-15

This amendment adopts a new airworthiness directive (AD), applicable to Eurocopter France Model AS 332C, L, L1, and L2 helicopters that requires visually inspecting the intermediate gearbox-to-structure attachment stirrup (stirrup) front tabs for cracks, and if a crack is discovered, removing the intermediate gearbox and replacing it with an airworthy intermediate gearbox; and inspecting for the conformity of the attachment parts. This amendment is prompted by five reports of failure of the two stirrup tabs. The actions specified by this AD are intended to prevent failure of the intermediate gearbox stirrup front tabs, loss of anti-torque drive, and subsequent loss of control of the helicopter.

Final rule

98-12-15 EUROCOPTER FRANCE: Amendment 39-10571. Docket No. 98-SW-07-AD.
Applicability: Model AS 332C, L, L1, and L2 helicopters, with intermediate gearboxes (IGB), part numbers (P/N) 332A35-0002 all dash numbers, 332A35-0010 all dash numbers, or 332A35-0011-01, installed, except those IGBs modified in accordance with MOD 0761049 or MOD 0761050, certificated in any category.

NOTE 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been 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 use the authority provided in paragraph (c) to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any helicopter from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of the IGB-to-structure attachment stirrup (stirrup) front tabs, loss of anti-torque drive, and subsequent loss of control of the helicopter, accomplish the following:

(a) Before the first flight of each day, perform a visual inspection of the stirrup front tabs for cracks in accordance with paragraph 2.B.1) of the Accomplishment Instructions in Eurocopter France AS 332 Service Bulletin 01.00.47, Revision No. 1, dated September 10, 1997 (SB). If a crack is found, remove the IGB and replace it with an airworthy IGB before further flight. Completion of the conformity procedure contained in paragraph 2.B.2.1.3) of the SB is terminating action for the requirement of this AD to inspect for cracks prior to the first flight of each day.

(b) Within 100 hours time-in-service (TIS), inspect the two front attaching assemblies securing the stirrup of the IGB to the angle bracket of the structure (attachment assembly) for thickness of the stirrup front tabs in accordance with paragraph 2.B.2) of the SB.

(1) If the attachment assembly meets the conformity requirements of either paragraph 2.B.2.1.1) or 2.B.2.1.2) of the SB, reassemble the attachment assembly in accordance with paragraph 2.B.2.1.3) of the SB.

(2) If the attachment assembly does not meet the conformity requirements of either paragraph 2.B.2.1.1) or 2.B.2.1.2) of the SB, replace it with an attachment assembly which does meet the conformity requirements of either of those paragraphs. Install the attachment assembly hardware in accordance with 2.B.2.1.3) of the SB.

(3) If a crack is discovered in the stirrup front tabs as a result of the conformity inspection, remove the IGB and replace it with an airworthy IGB before further flight.

(c) 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, Rotorcraft Directorate, Rotorcraft Standards Staff. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Rotorcraft Standards Staff.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Rotorcraft Standards Staff.

(d) 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.

(e) The inspections and replacement, if necessary, shall be done in accordance with Eurocopter France AS 332 Service Bulletin 01.00.47, Revision No. 1, dated September 10, 1997. 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. 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.

NOTE 3: The subject of this AD is addressed in Direction Generale De L'Aviation Civile (France) AD 96-263-060(AB)R1 for Eurocopter France (ECF) Model AS 332C, L, and L1 helicopters, and AD 96-262-004(AB)R1 for ECF Model AS 332L2 helicopters, both dated November 5, 1997.

(f) This amendment becomes effective on July 14, 1998.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to Eurocopter France Model AS 332C, L, L1, and L2 helicopters was published in the Federal Register on April 7, 1998 (63 FR 16916). That action proposed to require visually inspecting the stirrup front tabs for cracks, and if a crack is discovered, removing the intermediate gearbox and replacing it with an airworthy intermediate gearbox; and inspecting for the conformity of the attachment parts.

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 except for an editorial change in the "Applicability" section of the AD where the word "and" has been changed to "or." This change is to make it clear that this AD applies to the affected model helicopters when either of the three part numbers is installed. The FAA has determined that this change will neither increase the economic burden on an operator nor increase the scope of the AD.

The FAA estimates that 4 helicopters of U.S. registry will be affected by this AD, that it will take approximately 0.25 work hours to inspect the tabs, and 3 work hours to inspect for conformity, and that the average labor rate is $60 per work hour. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $780.

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 sufficientfederalism implications to warrant the preparation of a Federalism Assessment.

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 adding a new airworthiness directive to read as follows: