SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to send any written relevant data, views, or arguments regarding this proposed AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number, “FAA-2010-0122; Directorate Identifier 2009-CE-067-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://www.regulations.gov, including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive concerning this proposed AD.

Discussion

We have received reports that spot-welded V-band exhaust couplings that are installed on certain Piper Aircraft, Inc. Models PA-32R-301T and PA-46-350P airplanes are failing.

The V-band exhaust coupling attaches the exhaust pipe to the engine's turbocharger. The spot welds on the coupling can fail and the coupling may become detached from the turbocharger and expose the firewall to hot exhaust gases.

Several failures of part number 40D21162-340M, a Lycoming spot-welded coupling, on other airplane models have occurred, and some of the failures resulted in an in-flight fire. These failures caused us to issue the following ADs:

• AD 2004-23-17, Amendment 39-13872 (69 FR 67809, November 22, 2004), applicable to Mooney Airplane Company, Inc. Model M20M airplanes; and
• AD 2000-11-04, Amendment 39-11752 (65 FR 34941, June 1, 2000), applicable to Commander Aircraft Company Model 114TC airplanes.

A newer and more robust design V-band exhaust coupling has been developed by the Lycoming supplier that is assembled using rivets instead of spot welds.

This condition, if not corrected, could result in failure of the V-band exhaust coupling, which could cause the exhaust pipe to detach from the turbocharger. This failure could result in release of high temperature gases inside the engine compartment and possibly cause an in-flight fire. An in-flight fire could lead to loss of control.

FAA's Determination and Requirements of the Proposed AD

We are proposing this AD because we evaluated all information and determined the unsafe condition described previously is likely to exist or develop on other products of the same type design. This proposed AD would require replacing any spot-welded V-band exhaust coupling with a riveted V-band exhaust coupling.

Costs of Compliance

We estimate that this proposed AD could affect up to 596 airplanes in the U.S. registry provided they had the affected V-band exhaust coupling installed.

We estimate the following costs to do the proposed replacement: ( printed page 7408)

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.

Regulatory Findings

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. 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 regulatory evaluation of the estimated costs to comply with this proposed AD and placed it in the AD docket.

Examining the AD Docket

You may examine the AD docket that contains the proposed AD, the regulatory evaluation, any comments received, and other information on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone (800) 647-5527) is located at the street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.

The Proposed Amendment

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