07-26. Airworthiness Directives; Robinson Helicopter Company Model R44 and R44 II Helicopters

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes adopting a new airworthiness directive (AD) for robinson Helicopter Company (Robinson) Model R44 and R44 II helicopters that have a certain seat belt buckle (buckle) assembly installed. The AD would require removing the buckle assembly and the buckle assembly spacer, and replacing them with airworthy parts. This proposal is prompted by an accident in which a seat belt failed, and also by reports of cracking in the buckle assembly stainless support strap (support strap). The actions specified by the proposed AD are intended to prevent cracking in the support strap and failure of a seat belt.

DATES:

Comments must be received on or before March 12, 2007.

ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD:

• DOT Docket Web site: Go to http://dms.dot.gov and follow the instructions for sending your comments electronically;
• Government-wide rulemaking Web site: Go to http://www.regulations.gov follow the instructions for sending your comments electronically;
• Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, Washington, DC 20590;
• Fax: [phone]; or
• Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

You may get the service information identified in this proposed AD from Robinson Helicopter Company, 2901 Airport Drive, Torrance, California 90505, telephone [phone], fax [phone].

You may examine the comments to this proposed AD in the AD docket on the Internet at http://dms.dot.gov.

FOR FURTHER INFORMATION CONTACT:

Venessa Stiger, Aviation Safety Engineer, FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Blvd., Lakewood, California 90712-4137, telephone [phone], fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any written data, views, or arguments regarding this proposed AD. Send your comments to the address listed under the caption ADDRESSES. Include the docket number “FAA-2006-26696, Directorate Identifier 2006-SW-19-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light of those comments.

We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact with FAA personnel concerning this proposed rulemaking. Using the search function of our docket Web site, you can find and read the comments to any of our dockets, including the name of the individual who sent or signed the comment. You may review the DOT's complete Privacy Act Statement in the Federal Register published on April 11, 2000 (65 FR 19477-78) or you may visit http://dms.dot.gov.

Examining the Docket

You may examine the docket that contains the proposed AD, any comments, and other information in person at the Docket Management System (DMS) Docket Office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone [phone]) is located at the plaza level of the Department of Transportation Nassif Building in Room PL-401 at 400 Seventh Street, SW., Washington, DC. Comments will be available in the AD docket shortly after the DMS receives them.

Discussion

This document proposes adopting a new AD for Robinson model R44 helicopters, through serial number (S/N) 1576, and Model R44 II helicopters, through S/N 11107, that have a C628-4, revision M or prior, buckle assembly installed. The AD would require, within 100 hours time-in-service, removing the buckle assembly and the A130-52 buckle assembly spacer, and replacing them with a C628-4, revision N buckle assembly and a new A130-52 buckle assembly spacer. The A130-52 buckle assembly spacers have been redesigned to be slightly longer than the previous A130-52 buckle assembly spacers, to reduce friction in the joint. This proposal is prompted by an investigation in which a seat belt failed during an accident, and also by reports of cracking in the buckle assembly support strap. Excessive bending of the buckles can damage their stainless support straps. The actions specified by the proposed AD are intended to prevent cracking in the support strap and failure of a seat belt.

We have reviewed Robinson Service SB-56, dated March 29, 2006, which describes procedures for inspecting the buckle assemblies for cracks and replacing the buckle assemblies. This proposed AD would not require inspecting the buckle assemblies for cracks.

This unsafe condition is likely to exist or develop on other helicopters of the same type design. Therefore, the proposed AD would require removing any C628-4, revision M or prior, buckle assembly and any A130-52 buckle assembly spacer, and replacing them with a C628-4, revision N buckle assembly and a new A130-52 buckle assembly spacer. Replacing the buckle assembly and buckle assembly spacer with a C628-4, Revision N buckle assembly and a new A130-52 buckle assembly spacer would be the terminating action for the requirements of this proposed AD. The replacement would be required to be accomplished by following specified portions of the service bulletin described previously.

We estimate that this proposed AD would affect 900 helicopters of U.S. registry, and replacing a buckle assembly would take approximately 0.2 work hour per buckle to accomplish at an average labor rate of $80 per work hour. Required parts would cost approximately $105 for each C628-4, revision N buckle assembly, and $8.25 for each A130-52 buckle assembly spacer. Based on these figures, the total cost impact of the proposed AD on U.S. operators would be $517 for each helicopter, or $465,300 for the entire fleet, assuming that four buckle assemblies and buckle assembly spacers are replaced in each helicopter.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. Additionally, this proposed AD 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.

For the reasons discussed above, I certify that the 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); 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.

We prepared a draft economic evaluation of the estimated costs to comply with this proposed AD. See the DMS to examine the draft economic evaluation.

Authority for This Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

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 adding a new airworthiness directive to read as follows:

Robinson Helicopter Company: Docket No. FAA-2006-26696; Directorate Identifier 2006-SW-19-AD.

Applicability: Model R44 helicopters, through serial number (S/N) 1576, and Model R44 II helicopters, through S/N 11107, with a seat belt buckle assembly (buckle assembly) part number C628-4, revision M or prior, installed, certificated in any category.

Compliance: Required within 100 hours time-in-service, unless accomplished previously.

To prevent cracking in the buckle assembly stainless support strap and failure of a seat belt, accomplish the following:

(a) Remove the buckle assembly and any A130-52 buckle assembly spacer, and replace them with a C628-4, revision N buckle assembly and a new A130-52 buckle assembly spacer, in accordance with the Compliance Procedure, paragraph 3, in Robinson Helicopter Company Service Bulletin SB-56, dated March 29, 2006. The new A130-52 buckle assembly spacers have been redesigned to be slightly longer than the previous A130-52 buckle assembly spacers, to reduce friction in the joint.

Note:

Inspecting the buckle assembly for cracks is not required by this AD.

(b) Replacing the buckle assembly and buckle assembly spacer with a C628-4, Revision N buckle assembly and a new A130-52 buckle assembly spacer is a terminating action for the requirements of this AD.

(c) to request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. Contact the Manager, Los Angeles Aircraft Certification Office, FAA, ATTN: Venessa Stiger, Aviation Safety Engineer, 3960 Paramount Blvd., Lakewood, California 90712-4137, telephone [phone], fax [phone], for information about previously approved alternative methods of compliance.

Issued in Fort Worth, Texas, on December 18, 2006.

David A. Downey,

Manager, Rotorcraft Directorate, Aircraft Certification Service.