AD 2007-15-03

We are adopting a new airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Service experience showed that the connection screw of the propeller blade follower type 10AP-VM may break and the main part of the blade follower can be lost in flight. This condition, if not corrected, could lead to high vibration during powered flight and consequently result in decreased control of the aircraft.

We are issuing this AD to require actions to correct the unsafe condition on these products.

Final rule.

2007-15-03 Stemme GmbH & Co. KG: Amendment 39-15132; Docket No. FAA- 2007-27431; Directorate Identifier 2007-CE-016-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective August 28, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Models STEMME S10-V and STEMME S10-VT powered sailplanes, all serial numbers, that:

(1) Are certificated in any category; and

(2) Have not incorporated the actions in their entirety of STEMME F & D SB A31-10-078, Am.-index: 01.a, dated November 6, 2006, which references STEMME F & D Installation Instruction A34-10-078-E, Am.-index: 01.a, dated February 20, 2007.

Subject

(d) Air Transport Association of America (ATA) Code 61: Propellers.

Reason

(e) The mandatory continuing airworthiness information (MCAI) states:

Service experience showed that the connection screw of the propeller blade follower type 10AP-VM may break and the main part of the blade follower can be lost in flight. This condition, if not corrected, could lead to high vibration during powered flight and consequently result in decreased control of the aircraft.

Stemme has developed a new blade follower, Model 10AP-VP, which is reinforced on the shaft and has an Allen head screw installed instead of a slotted screw. For the reason stated above, this Emergency Airworthiness Directive (EAD) requires the replacement of the blade follower type 10AP-VM with the new type 10AP-VP.

This EAD has been revised to correct the TCDS reference and the applicability statement. No separate TC was issued for the affected propellers. These propellers are part of the aircraft type design.

Paragraph (4) of the "Compliance'' section of this EAD has been corrected.

Actions and Compliance

(f) Unless already done, within the next 25 engine operating hours after August 28, 2007 (the effective date of this AD) or 90 days after August 28, 2007 (the effective date of this AD), whicheveroccurs first, do the following actions:

(1) Replace the blade follower type 10AP-VM with the new type 10AP-VP following the instructions contained in STEMME F & D SB A31- 10-078, Am.-index: 02.a, dated March 2, 2007, which references STEMME F & D Installation Instruction A34-10-078-E, Am.-index: 01.a, dated February 20, 2007.

(2) As of 25 engine operating hours after August 28, 2007 (the effective date of this AD) or 90 days after August 28, 2007 (the effective date of this AD), whichever occurs first, do not install a propeller type 10AP-F, 10AP-V or 11AP-V on any aircraft, unless that propeller has the new type 10AP-VP blade follower installed following the instructions contained in STEMME F & D SB A31-10-078, Am.-index: 02.a, dated March 2, 2007, which references STEMME F & D Installation Instruction A34-10-078-E, Am.-index: 01.a, dated February 20, 2007.

FAA AD Differences

Note: This AD differs from the MCAI and/or service information as follows: The MCAI requires an amendment to the aircraft flight manual before further flight as an interim requirement to the replacement. We consider before flight as an urgent safety of flight compliance time, and we do not consider this unsafe condition to be an urgent safety of flight condition. We feel that 25 engine operating hours or 90 days, whichever occurs first, for the replacement is an adequate compliance for this AD action. We do encourage you to incorporate these flight manual amendments referenced in the MCAI and service information until you replace the propeller blade follower.

Other FAA AD Provisions

(g) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, Standards Staff, FAA, ATTN: Gregory Davison, Aerospace Engineer, FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri, 64106; telephone: (816) 329-4130; fax: (816) 329-4090, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Before using any approved AMOC on any airplane to which the AMOC applies, notify your appropriate principal inspector (PI) in the FAA Flight Standards District Office (FSDO), or lacking a PI, your local FSDO.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et. seq.), the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120-0056.

Related Information

(h) Refer to MCAI European Aviation Safety Agency (EASA) Emergency AD No.: 2006-0373R1-E, dated December 15, 2006, corrected January 5, 2007; STEMME F & D SB A31-10-078, Am.-index: 02.a, dated March 2, 2007; and STEMME F & D Installation Instruction A34-10-078- E, Am.-index: 01.a, dated February 20, 2007 for related information.

Material Incorporated by Reference

(i) You must use STEMME F & D SB A31-10-078, Am.-index: 02.a, dated March 2, 2007, which references STEMME F & D Installation Instruction A34-10-078-E, Am.-index: 01.a, dated February 20, 2007, to do the actions required by this AD, unless the AD specifies otherwise.

(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) For service information identified in this AD, contact Stemme GmbH & Co. KG, Gustav-Meyer-Allee 25, D-13355 Berlin, Germany; Telephone: 49.3341.3111.70; Facsimile: 49.3341.3111.73.

(3) You may review copies at the FAA, Central Region, Office of the Regional Counsel, 901 Locust, Room 506, Kansas City, Missouri 64106; or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal- register/cfr/ibr-locations.html .

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on April 23, 2007 (72 FR 20072). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states that:

Service experience showed that the connection screw of the propeller blade follower type 10AP-VM may break and the main part of the blade follower can be lost in flight. This condition, if not corrected, could lead to high vibration during powered flight and consequently result in decreased control of the aircraft.

Stemme has developed a new blade follower, Model 10AP-VP, which is reinforced on the shaft and has an Allen head screw installed instead of a slotted screw. For the reason stated above, this Emergency Airworthiness Directive (EAD) requires the replacement of the blade follower type 10AP-VM with the new type 10AP-VP.

This EAD has been revised to correct the TCDS reference and the applicability statement. No separate TC was issued for the affected propellers. These propellers are part of the aircraft type design.

Paragraph (4) of the "Compliance'' section of this EAD has been corrected.

Comments

We gave the public the opportunity to participate in developing this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Conclusion

We reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Differences Between This AD and the MCAI or Service Information

We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.

We might also have required different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a Note within the AD.

Costs of Compliance

We estimate that this AD will affect 53 products of U.S. registry. We also estimate that it will take about 3 work-hours per product to comply with basic requirements of this AD. The average labor rate is $80 per work-hour. Required parts will cost about $117 per product. Where the service information lists required parts costs that are covered under warranty, we have assumed that there will be no charge for these parts. As we do not control warranty coverage for affected parties, some parties may incur costs higher than estimated here. Based on these figures, we estimate the cost of this AD to the U.S. operators to be $18,921 or $357 per product.

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 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 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 AD docket contains the NPRM, the regulatory evaluation, anycomments received, and other information. The street address for the Docket Office (telephone (800) 647-5527) is 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, Aviation safety, 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 AD: