Discussion
The European Aviation Safety Agency (EASA), which is the airworthiness authority for the European Union (EU), recently notified the FAA that an unsafe condition may exist on certain Stemme GmbH & Co. KG Model STEMME S10-VT sailplanes. The EASA reports that deformations and cracks at an exhaust bend were found during maintenance work. The defective exhaust bend was found on the thermally topmost loaded front- left cylinder. The damaged area is located in the curvature bend near the cylinder flange. If not corrected, exhaust gases may expand into the engine compartment and/or CO may leak into the cockpit section.
Relevant Service Information
We reviewed Stemme GmbH & Co. KG Service Bulletin A31-10-075 Am.- Index: 01.a, dated July 06, 2006. The service information describes procedures for inspecting the exhaust pipes in the curvature bend near the exhaust flange, replacing any damaged pipes found, and reconditioning the heat protection wrapping.
The EASA classified this service bulletin as mandatory and issued EU AD No.: 2006-0217-E, dated July 17, 2006, to ensure the continued airworthiness of these sailplanes in the EU.
FAA's Determination and Requirements of This AD
These Stemme GmbH & Co. KG Model STEMME V10-VT sailplanes are manufactured in Germany and are type-certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement.
Under this bilateral airworthiness agreement, the EASA has kept us informed of the situation described above. We are issuing this AD because we evaluated all the information and determined the unsafe condition described previously is likely to exist or develop on other products of the same type design. This AD requires you to do a one-time inspection of all exhaust bends (each cylinder 1 to 4) in the area of the curvature bend near the cylinder flange, replace any damaged exhaust pipes found, and recondition the heat protection wrapping.
In preparing this rule, we contacted type clubs and aircraft operators to get technical information and information on operational and economic impacts. We did not receive any information through these contacts. If received, we would have included a discussion of any information that may have influenced this action in the rulemaking docket.
FAA's Determination of the Effective Date
Since an unsafe condition exists that requires the immediate adoption of this AD, we determined that notice and opportunity for public comment before issuing this AD are impracticable, and that good cause exists for making this amendment effective in fewer than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and an opportunity for public comment. We invite you to send any written relevant data, views, or arguments regarding this AD. Send your comments to an address listed under the ADDRESSES section. Include the docket number "FAA-2006- 25689; Directorate Identifier 2006-CE-45-AD" at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the AD. We will consider all comments received by the closing date and may amend the 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 we receive concerning this AD.
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 determined that 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); 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 AD and placed it in the AD docket.
Examining the AD Docket
You may examine the AD docket that contains the AD, the regulatory evaluation, any comments received, and other information on the Internet at http://dms.dot.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) 647-5227) is located at the street address stated in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviationsafety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD):