AD 98-06-12 ACTIVE

This amendment adopts a new airworthiness directive (AD) that is applicable to Eurocopter France Model AS-350B, BA, B1, B2, and D helicopters, and Model AS 355E, F, F1, F2, and N helicopters. This action requires replacing certain tailboom attachment bolts located above the cargo compartment floor. This amendment is prompted by two reports of attachment bolts strength properties not meeting design specifications during manufacture. The actions specified in this AD are intended to identify and remove the weaker bolts and to prevent the separation of the tailboom from the helicopter, and subsequent loss of control of the helicopter.

Final rule; request for comments

98-06-12 Eurocopter France: Amendment 39-10390. Docket No. 97-SW-33-AD.
Applicability: Model AS-350B, BA, B1, B2, and D helicopters, and Model AS 355E, F, F1, F2, and N 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 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 within 10 hours time-in-service (TIS), unless accomplished previously.

To identify and remove the weaker bolts and to prevent the separation of the tailboom from the helicopter, and subsequent loss of control of the helicopter, accomplish the following:

(a) For helicopters that either were delivered from the manufacturer with zero-time before May 16, 1997, were overhauled before May 16, 1997, or have had any tailboom attachment bolt (bolt), part number (P/N) 22201BC060008L, replaced after July 1, 1994:

(1) Inspect the markings on each of the 23 bolts located above the baggage compartment floor.

(2) Remove any of the 23 bolts, P/N 22201BC060008L, that are marked with the letter "M" above the designation "BC" and replace each of them, one-by-one, with an airworthy bolt, P/N 22201BC060008L, that is marked with a letter other than "M". Torque each replacement bolt to between 67 and 79 inch-lbs. using only new nuts.

NOTE 2: These inspections and replacements are not required for helicopters that were delivered from the manufacturer with zero-time after May 15, 1997, were overhauled after May 15, 1997, and have had no bolt, P/N 22201BC060008L, replaced after July 1, 1994.

NOTE 3: The inspection and replacement of the 4 bolts located below the baggage compartment are not required by this AD.

NOTE 4: Eurocopter France AS 350 Service Telex No. 01.00.46, Eurocopter France AD 355 Service Telex No. 01.00.43, and Work Card 53.00.00.402 pertain to this AD.

(b) Replacement of all the bolts, P/N 22201BC060008L, with airworthy bolts marked with a letter other than "M" constitutes terminating action for the requirements of this AD.

(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 theManager, Rotorcraft Standards Staff, 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, Rotorcraft Standards Staff.

NOTE 5: 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.

NOTE 6: The subject of this AD is addressed in Direction Generale De L'Aviation Civile (France) AD 97-146-054(AB) and AD 97-147-072(AB), both dated July 16, 1997.

(e) This amendment becomes effective on March 30, 1998.

The Direction Generale De L Aviation Civile (DGAC) which is the airworthiness authority for France, recently notified the FAA that an unsafe condition may exist on Eurocopter France Model AS-350B, BA, B1, B2, and D helicopters, and Model AS 355E, F, F1, F2, and N helicopters. The DGAC advises that due to the discovery of the installation of tailboom attachment bolts in the affected model helicopters which do not meet metallurgical design requirements, replacement of certain attachment bolts is required within 100 flying hours.

Eurocopter France has issued Eurocopter France Service Telex No. 00031/00153/97, dated June 2, 1997, (Eurocopter France AS 350 Service Telex No. 01.00.46 and Eurocopter France AS 355 Service Telex No. 01.00.43), which specifies checking the marking on the heads of the 23 attachment bolts of the tailboom-to-aircraft junction located above the baggage compartment floor, and scrapping all attachment bolts that are marked withthe letter "M" above the designation "BC"; and, replacing the unairworthy attachment bolts with airworthy attachment bolts, in accordance with the special instructions given in Maintenance Manual (MET) work card 53.00.00.402, paragraph 4. Replacement bolts must be marked with a symbol other than the letter "M". The DGAC classified this service telex as mandatory and issued DGAC AD 97-147-072(AB), and AD 97-146-054(AB), both dated July 16, 1997, in order to assure 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 provisions of section 21.29 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, anddetermined that AD action is necessary for products of this type design that are certificated for operation in the United States.

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 helicopters, and Model AS 355E, F, F1, F2, and N helicopters of the same type design registered in the United States, this AD is being issued to require the removal of understrength tailboom attachment bolts to prevent separation of the tailboom, and subsequent loss of control of the helicopter. This AD requires removal and replacement of certain tailboom attachment bolts within 10 hours time-in-service for helicopters that were delivered from the manufacturer prior to May 16, 1997, or were overhauled prior to May 16, 1997, or had any tailboom attachment bolts, part number (P/N) 22201BC060008L, replaced after July 1, 1994. If the helicopter meets either of those criteria, the AD requires an inspection of the marking on each of the 23 attachment bolts that are located above the baggage compartment floor, and replacement of any attachment bolt that is marked with the letter "M" above the designation " BC" on the head of the attachment bolts with an airworthy attachment bolt marked with a letter other than "M". 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 replacement of the attachment bolts is required within 10 hours time-in-service, 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.

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 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, both before andafter 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. 97-SW-33-AD." The postcard will be date stamped and returned to the commenter.

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 sufficient federalism implications to warrant the preparation of a Federalism Assessment.

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 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:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of Regional Counsel, Southwest Region, Attention: Rules Docket No. 97-SW-33-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Mr. Mike Mathias, Aerospace Engineer, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5123, fax (817) 222-5961.