AD 2001-20-18

This amendment adopts a new airworthiness directive (AD) for Robinson Helicopter Company (RHC) Model R44 helicopters that requires establishing a life limit of 2200 hours time-in-service (TIS) for affected horizontal stabilizers. This amendment is prompted by engineering analysis which indicates that certain vertical-to-horizontal stabilizer attach channels (channels) will crack sooner than the original life limit of the horizontal stabilizer. The actions specified by this AD are intended to prevent a crack through a channel, separation of the stabilizers, and subsequent loss of directional control of the helicopter.

Final rule

2001-20-18 Robinson Helicopter Company: Amendment 39-12466. Docket No. 2000-SW-67-AD.

Applicability: Model R44 helicopters, with horizontal stabilizer assembly (assembly), part number (P/N) C044-1; horizontal stabilizer serial number (S/N) 0009 through 0224, except S/N 0018, 0090, 0094, 0111, 0129, 0144, 0161, 0178, 0201, and 0223, 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 (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed bythis 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 crack through a vertical-to-horizontal stabilizer attach channel (channel), which can cause separation of the stabilizers and subsequent loss of control of the helicopter, accomplish the following:

(a) Before accumulating 2200 hours time-in-service (TIS) on the assembly:

(1) Remove the vertical stabilizer to inspect the nutplate on channels, P/N D283-1 and -2.

(2) If the nutplates are P/N MS21086L4, no further action is required by this AD.

(3) If the nutplates are P/N NAS697A4, replace the channels with airworthy channels, P/N D296-1 or -2.

Note 2: Robinson Helicopter Company Service Bulletin SB-39, dated September 12, 2000, pertains to the subject of this AD.

(b) This AD revises the Limitations section of the maintenance manual by establishing a retirement life of 2200 hours TIS for assembly, P/N CO44-1, with channels, P/N D283-1 or -2, with nutplates, P/N NAS697A4, installed.

(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, Los Angeles Aircraft Certification Office (LAACO), FAA. Operators shall submit their requests through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, LAACO.

Note 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the LAACO.

(d) 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.

(e) This amendment becomes effective on November 19, 2001.

A proposal to amend 14 CFR part 39 to include an AD for RHC R44 helicopters was published in the Federal Register on June 25, 2001 (66 FR 33653). That action proposed a life limit of 2200 hours TIS for affected horizontal stabilizers and removing, inspecting, and replacing certain channels with airworthy channels.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposal or the FAA's determination of the cost to the public. The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

The FAA estimates that 3 helicopters of U.S. registry will be affected by this AD, that it will take approximately 1/2 work hour per helicopter to inspect the horizontal stabilizer and replace the channels. The average labor rate is $60 per work hour. The manufacturer states in their service bulletin that there will be no charge for the parts. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $90.

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.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of itmay be obtained from the Rules Docket at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas.

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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding a new airworthiness directive to read as follows: