AD 2000-05-17

This amendment supersedes an existing airworthiness directive (AD), applicable to Eurocopter France Model EC 120B helicopters, that currently requires, at specified time intervals, inspecting the engine coupling tube for cracks and replacing any cracked engine coupling tube with an airworthy engine coupling tube. This amendment requires, at specified time intervals, visually inspecting and dye-penetrant inspecting the coupling tube for any crack and replacing any cracked coupling tube with a reinforced, airworthy coupling tube. Replacing all coupling tubes and certain engine support fitting components is required on or before March 31, 2000. This amendment is prompted by the discovery of cracks in several coupling tubes. The actions specified by this AD are intended to prevent coupling failure, loss of engine drive, and a subsequent forced landing.

Final rule; request for comments

2000-05-17 EUROCOPTER FRANCE: Amendment 39-11627. Docket No. 99-SW-85-AD. Supersedes AD 99-19-23, Amendment 39-11343, Docket No. 99-SW-53-AD.
Applicability: Model EC 120B helicopters with engine coupling tube (coupling tube), part number (P/N) C631A1002101, installed, 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 (e) 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 coupling failure, loss of engine drive, and a subsequent forced landing, accomplish the following:

(a) Within 10 hours time-in-service (TIS), and thereafter at intervals not to exceed 10 hours TIS except when required to perform the inspection required by paragraph (b) of this AD while each coupling tube, P/N C631A1002101, is installed, inspect for any crack in accordance with the Accomplishment Instructions, paragraph 2.B.1., of Eurocopter Service Bulletin No. 05-001, dated September 23, 1999 (SB 05-001).

(b) Within 10 hours TIS, and thereafter at intervals not to exceed 30 hours TIS, after each coupling tube, P/N C631A1002101, has been removed, inspect for any crack in accordance with paragraph 2.B.2. of SB 05-001.

NOTE 2: Operators are not required to inform the manufacturer when a crack is found.

(c) When a crackis found as a result of the inspections conducted in accordance with either paragraph (a) or (b) of this AD, or by March 31, 2000, whichever occurs first, replace the coupling tube with a reinforced, airworthy coupling tube, P/N C631A1101101, and replace the engine mount fittings in accordance with Eurocopter Service Bulletin No. SB 63-001, dated November 10, 1999, using new, airworthy, engine mount fitting components to replace the following:

o Teflon spacer, P/N C714A1010208;

o Black-colored spring washers, 10.2 x 28 Type-C;

o Blue-colored hinge yoke, P/N C714A1010212; and

o Special washer, P/N C714A1010213.

NOTE 3: Eurocopter Service Bulletin No. 01-002 pertains to unairworthiness of the four engine mount fitting components listed in paragraph (c) of this AD.

(d) Installing the reinforced, airworthy coupling tubes, P/N C631A1101101, and replacing the engine mount fitting components using new, airworthy, engine mount fitting components, as specified in paragraph (c) of this AD, constitutes terminating action for the requirements of this AD.

(e) 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, Regulations Group, Rotorcraft Directorate, FAA. 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 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group.

(f) 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.

(g) The inspections and modifications shall be done in accordance with the Accomplishment Instructions, paragraph 2.B.1., of Eurocopter Service Bulletin No. 05-001, dated September 23, 1999; Eurocopter Service Bulletin No. 63-001, dated November 10, 1999; and Eurocopter Service Bulletin No. 01-002, dated December 23, 1999. 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.

(h) This amendment becomes effective on March 27, 2000.

NOTE 5: The subject of this AD is addressed in Direction Generale de L'Aviation Civile (France) AD 1999-349-002(A) R2, dated November 3, 1999 and AD 2000-058-003(A), dated February 9, 2000.

On September 2, 1999, the FAA issued Emergency Priority Letter AD 99-19-23 and on September 22, 1999, issued the final rule; request for comments for AD 99-19-23, Amendment 39-11343 (64 FR 53623, October 4, 1999), to require within 10 hours time-in-service (TIS), and thereafter, at intervals not to exceed 10 hours TIS, inspecting a specified engine coupling tube for cracks and replacing any cracked engine coupling tube with an airworthy engine coupling tube. That action was prompted by the discovery, during routine maintenance inspections, of three cracked engine coupling tubes caused by structural resonance. That condition, if not corrected, could result in coupling failure, loss of engine drive, and a subsequent forced landing.

Since the issuance of that AD, the manufacturer has issued Eurocopter Service Bulletin No. 05-001, dated September 23, 1999, which introduces a new alternative check procedure. The Direction Generale de L'Aviation Civile (DGAC), which is the airworthiness authority for France, classified this service bulletin as mandatory and issued AD 1999-349-002(A) R2, dated November 3, 1999, to ensure the continued airworthiness of these helicopters in France. The manufacturer has also issued Eurocopter Service Bulletin No. 63-001, dated November 10, 1999, which recommends installing a reinforced coupling tube and disassembling the engine mount fitting assembly. The manufacturer then issued Eurocopter Service Bulletin No. 01-002, dated December 23, 1999, which declares that coupling tubes, P/N C631A1002101, and certain engine support fitting components are unfit for flight after March 31, 2000. The DGAC classified this service bulletin as mandatory and issued AD 2000-058-003(A), dated February 9, 2000, to ensure the continued airworthiness of these helicopters in France.

This helicopter model is manufactured in France and is type certificated for operation in the United States under the provision of section21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the DGAC has kept the FAA informed of the situation described above. The FAA has examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operations in the United States.

Since an unsafe condition has been identified that is likely to exist or develop on other Eurocopter France Model EC 120B helicopters of the same type design, this AD supersedes AD 99-19-23 to require periodic visual and dye-penetrant inspections on each coupling tube, replacement of any cracked coupling tube, and replacement of the coupling tube and certain engine mount fitting components on or before March 31, 2000. The actions must be accomplished in accordance with the service bulletins described previously. The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the structural integrity of the helicopter. Therefore, the actions stated previously must be accomplished at the specified time intervals, and this AD must be issued immediately.

Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

The FAA estimates that 12 helicopters will be affected by this proposed AD, that it will take approximately 1 work hour to visually inspect each coupling tube and 6.5 work hours to dye-penetrant inspect each coupling tube. Replacing each coupling tube and installing the engine mount fitting components will take approximately 12 work hours per helicopter. The average labor rate is $60. The manufacturer states that they will provide the components necessary for replacing the coupling tubes free of charge. Based on these figures and the manufacturer's representation that it will provide the repair parts free of charge, the total cost impact of the AD on U.S. operators is estimated to be $19,400, assuming 2 visual inspections, 2 dye-penetrant inspections, 1 coupling tube replacement, and 1 installation of the engine support fitting components on each helicopter.

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 forcomments 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. 99-SW-85-AD." The postcard will be date stamped and returned to the commenter.

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.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, 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 andplaced 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 removing Amendment 39-11343 (64 FR 53623, October 4, 1999), and by adding a new airworthiness directive (AD), Amendment 39-11627, to read as follows: