04-15667. Airworthiness Directives; Stemme GmbH & Co. Models S10, S10-V, and S10-VT Sailplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule.

SUMMARY:

The FAA adopts a new airworthiness directive (AD) for all Stemme GmbH & Co. Models S10, S10-V, and S10-VT sailplanes. This AD requires you to remove the drive shaft assembly and ship it to the service department of Stemme GmbH & Co. The engine is mounted behind the two side-by-side seats. The engine combined with the carbon fiber drive shaft turn the centrifugally extended propeller. After an initial visual inspection, the service department will perform an operational check to determine whether the drive shaft can be further used or must be replaced. Once corrective action is identified, a drive shaft will be shipped to you for installation. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. We are issuing this AD to detect and correct incorrectly glued drive shafts, which could result in drive shaft failure. During self-takeoff or critical periods of landing, failure of the drive shaft could lead to loss of control of the sailplane.

DATES:

This AD becomes effective on August 21, 2004.

As of August 21, 2004, the Director of the Federal Register approved the incorporation by reference of certain publications listed in the regulation.

ADDRESSES:

You may get the service information identified in this AD from Stemme GmbH & Co. AG, Flugplatzstraße F 2, Nr. 7, D-15344 Strausberg, Germany.

You may view the AD docket at FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 2003-CE-58-AD, 901 Locust, Room 506, Kansas City, Missouri 64106. Office hours are 8 a.m. to 4 p.m., Monday through Friday, except Federal holidays.

FOR FURTHER INFORMATION CONTACT:

Gregory Davison, Aerospace Engineer, Small Airplane Directorate, ACE-112, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: 816-329-4090.

SUPPLEMENTARY INFORMATION:

 

Discussion

What events have caused this AD? The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, recently notified FAA that an unsafe condition may exist on all Stemme GmbH & Co. Models S10, S10-V, and S10-VT sailplanes. The LBA reports that two drive shafts have failed during normal operation of the sailplane. The flanges of the drive shafts started to rotate within the carbon fiber reinforced plastics-tube (CFRP-tube), while the drive shafts still appeared to be intact when looking at them from the outside. The metal flanges on both ends of the drive shafts might not have been properly glued to the CFRP-tube.

What is the potential impact if FAA took no action? Incorrectly glued drive shafts could result in drive shaft failure. This failure could lead to loss of control of the sailplane.

Has FAA taken any action to this point? We issued a proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to all Stemme GmbH & Co. Models S10, S10-V, and S10-VT sailplanes. This proposal was published in the Federal Register as a notice of proposed rulemaking (NPRM) on April 16, 2004 (69 FR 74). The NPRM proposed to require you to remove the drive shaft assembly and ship it to the service department of Stemme GmbH & Co. After an initial visual inspection, the service department will perform an operational check to determine whether the drive shaft can be further used or must be replaced. Once corrective action is taken, the NPRM also proposed to require you to install the returned drive shaft.

Comments

Was the public invited to comment? We provided the public the opportunity to participate in developing this AD. We received no comments on the proposal or on the determination of the cost to the public.

Conclusion

What is FAA's final determination on this issue? We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed except for minor editorial corrections. We have determined that these minor corrections:

—Are consistent with the intent that was proposed in the NPRM for correcting the unsafe condition; and

—Do not add any additional burden upon the public than was already proposed in the NPRM.

Changes to 14 CFR Part 39—Effect on the AD

How does the revision to 14 CFR part 39 affect this AD? On July 10, 2002, the FAA published a new version of 14 CFR part 39 (67 FR 47997, July 22, 2002), which governs the FAA's AD system. This regulation now includes material that relates to altered products, special flight permits, and alternative methods of compliance. This material previously was included in each individual AD. Since this material is included in 14 CFR part 39, we will not include it in future AD actions.

Costs of Compliance

How many sailplanes does this AD impact? We estimate that this AD affects 57 sailplanes in the U.S. registry.

What is the cost impact of this AD on owners/operators of the affected sailplanes? We estimate the following costs to remove the drive shaft, ship it to and from manufacturer's service department, and install the drive shaft after manufacturer's inspection is complete:

Labor cost	Parts cost	Shipping cost to and from manufacturer	Total cost per sailplane	Total cost on U.S operations
6 workhours × $65 per hour = $390	N/A	$1,080	$1,470	$83,790

We estimate the following costs for the manufacturer to do the inspection and any necessary repairs that will be required based on the results of this inspection. We have no way of determining the number of sailplanes that may need this repair:

Labor cost	Parts cost	Total cost per sailplane
Inspection and testing by manufacturer—$210	N/A	$210
Replacement of drive shaft—labor is included in the parts cost	$5,780	5780

Regulatory Findings

Will this AD impact various entities? We have 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.

Will this AD involve a significant rule or regulatory action? 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 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 summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary by sending a request to us at the address listed under ADDRESSES. Include “AD Docket No. 2003-CE-58-AD” in your request.

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 Federal Aviation Administration amends 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. FAA amends § 39.13 by adding a new AD to read as follows:

2004-14-21 Stemme GmbH & Co.: Amendment 39-13730; Docket No. 2003-CE-58-AD.

When Does This AD Become Effective?

(a) This AD becomes effective on August 21, 2004.

What Other ADs Are Affected by This Action?

(b) None.

What Sailplanes Are Affected by This AD?

(c) This AD affects the following sailplane models and serial numbers that are certificated in any category:

Models	Serial nos.
(1) S10-VT	11-001 through 11-055, 11-057, 11-058, and 11-060 through 11-066;
(2) S10-V	14-003, 14-004, 14-007, 14-014, 14-015, and 14-018 through 14-030, as well as conversion serial numbers 14-028M, 14-036M, and 14-038M; and 10-08 and 10-13.
(3) S10	10-08 and 10-13.

What Is the Unsafe Condition Presented in This AD?

(d) The actions specified in this AD are intended to identify incorrectly glued drive shafts, which could result in drive shaft failure. This failure could lead to loss of control of the sailplane.

What Must I Do To Address This Problem?

(e) To address this problem, you must do the following:

Actions	Compliance	Procedures
(1) Remove the drive shaft and ship it to the service department of Stemme GmbH & Co. for inspection at the following address: Stemme GmbH & Co. AG, Flugplatzstraße F 2, Nr. 7, D-15344 Strausberg, Germany. The sailplane's Component History Card and information about the current operating times (time since new, time since overhaul) must be included	Do within 50 hours time-in-service after August 21, 2004 (the effective date of this AD)	Follow the procedures in the Stemme GmbH & Co. Service Bulletin A31-10-058, dated November 8, 2001.
(2) Install the drive shaft after Stemme GmbH & Co. has performed the inspections, determined corrective action, and returned the drive shaft	Before further flight after receiving the returned drive shaft	Follow the procedures in the Stemme GmbH & Co. Service Bulletin A31-10-058, dated November 8, 2001.

May I Request an Alternative Method of Compliance?

(f) You may request a different method of compliance or a different compliance time for this AD by following the procedures in 14 CFR 39.19. Unless FAA authorizes otherwise, send your request to your principal inspector. The principal inspector may add comments and will send your request to the Manager, Standards Office, Small Airplane Directorate, FAA. For information on any already approved alternative methods of compliance, contact Gregory M. Davison, Aerospace Engineer, Small Airplane Directorate, ACE-112, 901 Locust, Room 301, Kansas City, Missouri 64106; telephone: [phone]; facsimile: 816-329-4090.

Does This AD Incorporate Any Material by Reference?

(g) You must do the actions required by this AD following the instructions in Stemme GmbH & Co. Service Bulletin A31-10-058, dated November 8, 2001. The Director of the Federal Register approved the incorporation by reference of this service bulletin in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may get a copy from Stemme GmbH & Co., Flugplatzstraße F 2, Nr. 7, D-15344 Strausberg, Germany. You may review copies at 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 [phone], or go to: http://www.archives.gov/​federal_​register/​code_​of_​federal_​regulations/​ibr_​locations.html.

Is There Other Information That Relates to This Subject?

(h) LBA Airworthiness Directive No. 2002-113, dated May 2, 2002, and Stemme GmbH & Co. Service Bulletin A31-10-058, dated November 8, 2001, also address the subject of this AD.

Issued in Kansas City, Missouri, on June 30, 2004.

David R. Showers,

Acting Manager, Small Airplane Directorate, Aircraft Certification Service.