AD 2001-04-12

This amendment adopts a new airworthiness directive (AD) for Eurocopter France Model EC120B helicopters. This action requires visually checking the engine to main gearbox coupling tube assembly (tube) for a crack and replacing any cracked tube. This amendment is prompted by a report of a crack detected on a tube. The actions specified by this AD are intended to prevent a tube failure, loss of engine drive, and a subsequent forced landing.

Final rule; request for comments

2001-04-12 EUROCOPTER FRANCE: Amendment 39-12131. Docket No. 2000-SW-31-AD.
Applicability: Model EC120B helicopters, with engine to main gearbox (MGB) coupling tube assembly (tube), part number C631A1101101, 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 (d) 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 a tube failure, loss of engine drive, and a subsequent forced landing, accomplish the following:

(a) Within 5 hours time-in-service (TIS) and thereafter at intervals not to exceed 5 hours TIS, visually check each affected tube for a crack as follows:

(1) Open the left and right cowlings.
(2) Check inside the MGB in the area of the tube cylindrical casing on either side of the fitting that attaches the tube to the MGB.

(b) Before further flight, replace any cracked tube with an airworthy tube.

Note 2: Eurocopter France Service Bulletin 05-003, dated July 20, 2000, pertains to the subject of this AD.

(c) An owner/operator (pilot) holding at least a private pilot certificate may perform the visual check required by paragraph (a) and must enter compliance with paragraph (a) of this AD into the aircraft maintenance records in accordance with 14 CFR 43.11 and 91.417(a)(2)(v).

(d) 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 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Regulations Group.

(e) Special flight permits will not be issued.

(f) This amendment becomes effective on March 20, 2001.

Note 4: The subject of this AD is addressed in Direction General De L'Aviation Civile (France), AD 2000-176-004(A) R1, dated August 23, 2000.

The Direction Generale De L'Aviation Civile (DGAC), the airworthiness authority for France, notified the FAA that an unsafe condition may exist on Eurocopter France Model EC120B helicopters equipped with tube, part number (P/N) C631A1101101. The DGAC advises that a crack was reported on a reinforced tube, which may lead to a tube failure.

Eurocopter France has issued Eurocopter Service Bulletin 05-003, dated July 20, 2000, which specifies visually checking each tube, P/N C631A1101101, for a crack.

This helicopter model is manufactured in France and is type certificated for operation in the United States under the provisions of 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 operation in the United States.

Since we have identified an unsafe condition that is likely to exist or develop on other Eurocopter France Model EC120B helicopters of the same type design registered in the United States, this AD is being issued to prevent failure of a tube, P/N C631A1101101. This AD requires visually checking each tube, P/N C631A1101101, for a crack. The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the structural integrity of the helicopter. Therefore, visually checking each tube, P/N C631A1101101, for a crack within the next 5 hours time-in-service (TIS) and thereafter at intervals not to exceed 5 hours TIS and replacing any cracked tube with an airworthy tube before further flight are required, and this AD must be issued immediately.

The owner/operator (pilot) may perform the visual check required by this AD and must enter compliance with paragraph (a) of this AD into the aircraft maintenance records in accordance with 14 CFR 43.11 and 91.417(a)(2)(v). This AD allows a pilot to perform this check because it involves only a visual check for a cracked tube and can be performed equally well by a pilot or a mechanic.

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 30 helicopters will be affected by this proposed AD, that it will take approximately 2 work hours to check the tube, and that the average labor rate is $60 per work hour. A replacement tube will cost approximately $4020 per helicopter and will require approximately 2 work hours to install. Based on these figures and on an assumption of one replacement and 100 checks per year per helicopter, the total cost impactof the AD on U.S. operators is estimated to be $484,200.

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 dates for comments 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 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 mailed 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. 2000-SW-31-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 and placed 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, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of theFederal 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: