AD 98-24-22 ACTIVE

This amendment adopts a new airworthiness directive (AD) that is applicable to Agusta A109C helicopters. This action requires, within the next 5 hours time-in-service (TIS), replacing the tail rotor blade grip assemblies (grip assemblies) with modified airworthy grip assemblies. This amendment is prompted by cracks that were found on the grip assemblies during maintenance inspections. This condition, if not corrected, could result in separation of a tail rotor blade and subsequent loss of control of the helicopter.

Final rule; request for comments

98-24-22 AGUSTA S.p.A.: Amendment 39-10907. Docket No. 98-SW-14-AD.

Applicability: Agusta A109C helicopters, all serial numbers (S/N) through 7670, excluding S/Ns 7630, 7633, 7645, 7651, 7653, 7657, 7661, 7663, 7665, 7667, and 7669, with tail rotor grip assembly (grip assembly), part number (P/N) 109-8131-05-109 or -113, 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 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: Within the next 5 hours time in service, unless accomplished previously.

To prevent cracks from developing on the grip assemblies that could result in separation of a tail rotor blade and subsequent loss of control of the helicopter, accomplish the following:

(a) Install airworthy grip assemblies, P/N 109-8131-29-101, or airworthy rotor grip and bushing assemblies, P/N 109-8131-02-129; and airworthy tail rotor blades, P/N 109-8132-01-107.

NOTE 2: Agusta Bollettino Tecnico No. 109-100, dated March 21, 1997, pertains to the subject of this AD.

(b) This AD revises the Limitations Section of the maintenance manual by establishing new retirement times for the tail rotor huband blade assembly components as follows:

Part Number
Nomenclature
Retirement Life (Hours)
109-8132-01-1
Blade
3000
109-8131-07-1
Retention Strap Assembly
2000
109-8131-08-1
Strap Pin
5000
109-8131-06-1
Strap Plug
5000
109-0131-06-7
Hub Assembly
3600
109-8131-09-1
Bolt, Retention Strap
5000
109-8131-29-101
Grip Assembly
3000

(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, Rotorcraft Standards Staff, FAA, 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, Rotorcraft Standards Staff.

NOTE 3: 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 4: The subject of this AD is addressed in Registro Aeronautico Italiano (Italy) AD 97-084, dated March 28, 1997.

(e) This amendment becomes effective on December 9, 1998.

The Registro Aeronautico Italiano (RAI), which is the airworthiness authority for Italy, recently notified the FAA that an unsafe condition may exist on Agusta A109C helicopters. The RAI advises that cracks on the grip assemblies could result in separation of a tail rotor blade and subsequent loss of control of the helicopter.

Agusta has issued Agusta Bollettino Tecnico No. 109-100, Revision A, dated March 21, 1997 (technical bulletin), which specifies replacement of the grip assemblies. The RAI classified this technical bulletin as mandatory and issued RAI AD 97-084, dated March 28, 1997, in order to assure the continued airworthiness of these helicopters in Italy.

This helicopter model is manufactured in Italy 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 RAI has kept the FAA informed of the situation described above. The FAA has examined the findings of the RAI, 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 an unsafe condition has been identified that is likely to exist or develop on other Agusta A109C helicopters of the same type design registered in the United States, this AD is being issued to prevent separation of a tail rotor blade and subsequent loss of control of the helicopter. This AD requires replacing the grip assemblies. The short compliance time involved is required because the previously described critical unsafe condition can adversely affect the controllability and structural integrity of the helicopter. Therefore, replacing the grip assemblies is required within the next 5 hours TIS, 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 17 helicopters will be affected by this proposed AD, that it will take approximately 10 work hours to replace the grip assemblies, and that the average labor rate is $60 per work hour. Required parts will cost approximately $18,286 per helicopter. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $321,062 to replace the grip assemblies on all helicopters.

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 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 inthe 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. 98-SW-14-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 the Regional Counsel, Southwest Region, Attention: Rules Docket No. 98-SW-14-AD, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Mr. Shep Blackman, Aerospace Engineer, FAA, Rotorcraft Directorate, Rotorcraft Standards Staff, 2601 Meacham Blvd., Fort Worth, Texas 76137, telephone (817) 222-5296, fax (817) 222-5961.