AD 2013-05-14

This AD is effective April 26, 2013.

For service information identified in this AD, contact Bell Helicopter Textron, Inc., P.O. Box 482, Fort Worth, TX 76101; telephone (817) 280-3391; fax (817) 280-6466; or at http://www.bellcustomer.com/files/. You may review a copy of the referenced service information at the FAA, Office of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, Texas 76137.

Michael Kohner, Aviation Safety Engineer, Rotorcraft Certification Office, Rotorcraft Directorate, FAA, 2601 Meacham Blvd., Fort Worth, TX 76137; telephone (817) 222-5447; email 7-avs-asw-170@faa.gov.

On September 24, 2012, at 77 FR 58794, the Federal Register published our notice of proposed rulemaking (NPRM), which proposed to amend 14 CFR part 39 to include an AD that would apply to Bell Model 412 and 412EP helicopters, with an outer ring, part number (P/N) 412-010-407-105. That NPRM proposed to require establishing a lower life limit on certain outer rings, revising the retirement life on the components' history card or equivalent record, and revising the maintenance manual or ICA. The proposal also proposed prohibiting the installation of these outer rings on any helicopter. The outer rings had a life limit of 10,000 hours TIS, but Bell has recommended reducing that limit to 2,500 hours TIS because of reports of cracking in the outer rings. The proposed requirements were intended to prevent failure of an outer ring, which could lead to the loss of M/R blade pitch control and subsequent loss of helicopter control.

We gave the public the opportunity to participate in developing this AD, but we received no comments on the NPRM (77 FR 58794, September 24, 2012).

We have reviewed the relevant information and determined that an unsafe condition exists and is likely to exist or develop on other products of these same type designs and that air safety and the public interest require adopting the AD requirements as proposed with minor editorial changes. These changes are consistent with the intent of the proposals in the NPRM (77 FR 58794, September 24, 2012) and will not increase the economic burden on any operator nor increase the scope of the AD.

We have reviewed Bell Helicopter Alert Service Bulletin No. 412-08-131, Revision B, dated October 29, 2009 (ASB), which describes procedures for establishing a new retirement life for the outer ring and replacing the outer ring at 2,500 hours TIS.

The ASB sets a calendar date for compliance. This AD does not.

We estimate that this AD affects 143 helicopters. We estimate that it takes about 1 work-hour to revise the component history card or equivalent record, as well as the maintenance manual or ICA, at an average labor rate of $85 per work hour, for a total cost of $85 per helicopter and $12,155 for the U.S. operator fleet. Replacing an outer ring takes 26 work-hours and required parts costs an estimated $25,725. Based on these figures, we calculate the total cost to be $27,935 per helicopter to replace an outer ring.

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.

This AD will not have federalism implications under Executive Order 13132. This AD 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.

For the reasons discussed above, I certify that this AD:

(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);

(3) Will not affect intrastate aviation in Alaska to the extent that it justifies making a regulatory distinction; and

(4) 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 an economic evaluation of the estimated costs to comply with this AD and placed it in the AD docket.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):