01-22947. Airworthiness Directives; Bell Helicopter Textron, Inc. Model 206A, 206B, 206A-1, 206B-1, 206L, and 206L-1 Helicopters

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of Proposed rulemaking (NPRM).

SUMMARY:

This document proposes to revise an existing airworthiness directive (AD) for Bell Helicopter Textron, Inc. (BHTI) Model 206A, 206B, 206A-1, 206B-1, 206L, and 206L-1 helicopters that currently establishes a retirement life for the main rotor trunnion (trunnion) based on hours time-in-service (TIS). This action would retain those requirements but would revise the AD to remove the trunnion, part number (P/N) 206-011-120-103, from the applicability. This proposal is prompted by the issuance of another AD for the BHTI Model 206L and 206L-1 helicopters that requires a different method of calculating the retirement life for the trunnions. The actions specified by this AD are intended prevent failure of the trunnion due to fatigue cracks and subsequent loss of control of the helicopter.

DATES:

Comments must be received by November 13, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 81-ASW-27, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137. You may also send comments electronically to the Rules Docket at the following address: [e-mail].

FOR FURTHER INFORMATION CONTACT:

Sharon Miles, Aviation Safety Engineer, FAA, Rotorcraft Directorate Regulations Group, Fort Worth, Texas 76193-0111, telephone [phone], fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed 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 above. All communications received on or before the closing date for comments will be considered before taking action on the proposed rule. The proposals contained in this document may be changed in light of the comments received.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their mailed comments submitted in response to this proposal must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket No. 81-ASW-27.” The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Office of the Regional Counsel, Southwest Region, Attention: Rules Docket No. 81-ASW-27, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Discussion

The FAA issued AD 81-18-01, Amendment 39-4192 (46 FR 42651, August 24, 1981), to require a retirement life on the trunnions installed on BHTI Model 206A, 206B, 206A-1, 206B-1, 206L, and 206L-1 helicopters. That action was prompted by the FAA's determination that a retirement life should be imposed on the trunnion based on fatigue testing, fatigue analysis, and service experience. That condition, if not corrected, could result in failure of the trunnion due to fatigue cracks and subsequent loss of control of the helicopter.

Since the issuance of AD 81-18-01, the FAA has issued AD 99-17-19 (64 FR 45433, August 20, 1999) that required a different method of calculating the retirement life for the trunnion, part number (P/N) 206-011-120-103, installed on BHTI Model 206L series helicopters. AD 81-18-01 established a retirement life for certain trunnions based on hours TIS. AD 99-17-19 requires a retirement life based on a Retirement Index Number (RIN) for the trunnion, P/N 206-011-120-103, installed on the Model 206L series helicopters. This AD revises AD 81-18-01 to remove the trunnion, P/N 206-011-120-103, from the applicability of that AD so that the trunnions for those models will only be affected by the RIN retirement life as required by AD 99-17-19. However, the model 206L and 206L-1 helicopters must be included in this AD because the other trunnions affected by the AD may be installed on these helicopters.

Since we have identified an unsafe condition that is likely to exist or develop on other BHTI Model 206A, 206B, 206A-1, 206B-1, 206L, and 206L-1 helicopters of the same type designs, the proposed AD would revise AD 81-18-01. This AD would contain the same requirements as AD 81-18-01 but would remove trunnion, P/N 206-011-120-103, from the applicability of that AD.

The FAA estimates that since the requirements of the AD are not changed and fewer helicopters of U.S. registry will be affected by this proposed AD revision, there will be no additional cost impact from the AD revision on U.S. operators.

The regulations proposed herein would 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 proposal would not have federalism implications under Executive Order 13132.

For the reasons discussed above, I certify that this proposed regulation (1) is not a “significant regulatory action” under Executive Order 12866; (2) is not a “significant rule” under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); (3) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action 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
• Safety

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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 39-4192 (46 FR 42651, August 24, 1981), and by adding a new airworthiness directive (AD) to read as follows:

Bell Helicopter Textron, Inc.: Docket No. 81-ASW-27. Revises AD 81-18-01, Amendment 39-4192, Docket No. 81-ASW-27.

Applicability

Model 206A, 206B, 206A-1, 206B-1, 206L, and 206L-1 helicopters, with main rotor (trunnion), part number (P/N) 206-010-104-3, 206-011-113-001, 206-011-120-001, or 206-011-113-103, 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 (i) 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 failure of the trunnion due to fatigue cracks, accomplish the following:

(a) Any trunnion, P/N 206-011-120-001, with 1100 or more hours time-in-service (TIS) must be retired from service within the next 100 hours TIS.

(b) Any trunnion, P/N 206-011-120-001, with less than 1100 hours TIS must be retired from service on or before attaining 1200 hours TIS.

(c) Any trunnion, P/N 206-010-104-3, and 206-011-113-001, with 2300 or more hours TIS must be retired from service within the next 100 hours TIS.

(d) Any trunnion, P/N 206-010-104-3, and 206-011-113-001, with less than 2300 hours TIS must be retired from service on or before attaining 2400 hours TIS.

(e) Any trunnion, P/N 206-011-113-103, with 4700 or more hours TIS must be retired from service within the next 100 hours TIS.

(f) Any trunnion, P/N 206-011-113-103, with less than 4700 hours TIS must be retired from service on or before attaining 4800 hours TIS.

(g) The retirement times, for the trunnions, established by this AD, are as follows:

P/N	Service life hours TIS
206-011-120-001	1200
206-010-104-3	2400
206-011-113-001	2400
206-011-113-103	4800

Note 2:

The FAA issued AD 99-17-19 (64 FR 45433, August 20, 1999) to establish a retirement life for trunnion, P/N 206-011-120-103.

(h) This AD revises the Limitations section of the maintenance manual by establishing a retirement life of 1200 hours TIS for trunnion, P/N 206-011-120-001; 2400 hours TIS for P/N 206-010-104-3 and 206-011-113-001; and 4800 hours TIS for P/N 206-011-113-103.

Note 3:

Bell Helicopter Textron Alert Service Bulletins 206-80-7 and 206L-80-9, both Revision B, and dated October 15, 1980, pertain to the subject of this AD.

(i) 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.

(j) Special flight permits may be issued in accordance with 14 CFR 21.197 and 21.199 to operate the helicopter to a location where the requirements of this AD can be accomplished.

Issued in Fort Worth, Texas, on September 4, 2001.

David A. Downey,

Manager, Rotorcraft Directorate, Aircraft Certification Service.