2022-00348. Airworthiness Directives; Stemme AG Gliders

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Final rule; request for comments.

SUMMARY:

The FAA is adopting a new airworthiness directive (AD) for certain Stemme AG Model Stemme S 10-VT and Stemme S 12 gliders. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI identifies the unsafe condition as unintended slipping of the freewheel clutch with overheating (burnishing) of the friction pads inside of the clutch. This AD requires removing the affected freewheel clutch from service. The FAA is issuing this AD to address the unsafe condition on these products.

DATES:

This AD is effective January 27, 2022.

The FAA must receive comments on this AD by February 28, 2022.

ADDRESSES:

You may send comments, using the procedures found in 14 CFR 11.43 and 11.45, by any of the following methods:

• Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.

• Fax: [phone].

• Mail: U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

• Hand Delivery: Deliver to Mail address above between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this AD, contact Stemme AG, Flugplatzstrasse F2, Nr. 6-7, D-15344 Strausberg, Germany; phone: [phone]; fax: [phone]; email: [e-mail]; website: https://www.stemme.com. You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call [phone].

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-1175; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this final rule, the MCAI, any comments received, and other information. The street address for Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT:

Jim Rutherford, Aviation Safety Engineer, General Aviation & Rotorcraft Section, International Validation Branch, FAA, 901 Locust, Room 301, Kansas City, MO 64106; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

Discussion

The European Union Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union, has issued EASA AD 2021-0278-E, dated December 15, 2021 (referred to after this as “the MCAI”), to address an unsafe condition on Stemme AG Model Stemme S10-VT and Stemme S12 gliders. The MCAI states:

Occurrences have been reported of unintended slipping of the freewheel clutch (P/N 12AK) during operation and, subsequently, overheating (burnishing) of the friction pads inside of the clutch.

This condition, if not corrected, could lead to total loss of thrust, possibly resulting in loss of control of the powered sailplane.

Even after a successful implementation of the recommendations for safe operation of the clutch, published in Stemme AG Service Information P064-8900057/01, it has been determined that loss of thrust could occur without signs in advance.

To address this potential unsafe condition, Stemme AG issued the SB [service bulletin], as defined in this AD, to provide applicable instructions.

For the reasons described above, this [EASA] Emergency AD prohibits operation of certain powered sailplanes [glider], and prohibits installation of affected parts.

This [EASA] AD is considered to be an interim action and further AD action may follow.

You may examine the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-1175.

Related Service Information

The FAA reviewed Stemme Service Bulletin Doc. No. P062-980058, Revision 1, dated December 14, 2021. This service information specifies procedures for identifying the serial number of a part number (P/N) 12AK freewheel clutch.

FAA's Determination

This product has been approved by the aviation authority of another country and is approved for operation in the United States. Pursuant to the FAA's bilateral agreement with this State of Design Authority, it has notified the FAA of the unsafe condition described in the MCAI and service information referenced above. The FAA is issuing this AD after determining the unsafe condition is likely to exist or develop in other products of the same type design.

AD Requirements

This AD applies to gliders with a P/N 12AK freewheel clutch with a serial number starting with “12-” and requires removing the freewheel clutch from service. This AD also prohibits installing a P/N 12AK freewheel clutch with a serial number starting with “12-” on any glider.

Differences Between This AD and the MCAI

The MCAI applies to all Stemme AG Model Stemme S10-VT and Stemme S12 gliders and requires an inspection to determine whether an affected P/N 12AK freewheel clutch is installed. This AD only applies to Stemme AG Model Stemme S 10-VT and Stemme S 12 gliders with an affected P/N 12AK freewheel clutch installed.

In addition, EASA considers its MCAI as interim action. The FAA does not identify this AD as interim action since there is no indication that a modification of the affected freewheel clutch is forthcoming and since this AD requires removing the affected clutch from service.

FAA's Justification and Determination of the Effective Date

Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 U.S.C. 551 et seq. ) authorizes agencies to dispense with notice and comment procedures for rules when the agency, for “good cause,” finds that those procedures are “impracticable, unnecessary, or contrary to the public interest.” Under this section, an agency, upon finding good cause, may issue a final rule without providing notice and seeking comment prior to issuance. Further, section 553(d) of the APA authorizes agencies to make rules effective in less than thirty days, upon a finding of good cause.

An unsafe condition exists that requires the immediate adoption of this AD without providing an opportunity for public comments prior to adoption. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because unintended slipping of the freewheel clutch and the consequent overheating (burnishing) of the friction pads inside of the clutch could result in a loss of thrust and loss of glider control. Because this could happen without advance warning, the corrective action must be accomplished before further flight. Accordingly, notice and opportunity for prior public comment are impracticable and contrary to the public interest pursuant to 5 U.S.C. 553(b)(3)(B).

In addition, the FAA finds that good cause exists pursuant to 5 U.S.C. 553(d) for making this amendment effective in less than 30 days, for the same reasons the FAA found good cause to forego notice and comment.

Comments Invited

The FAA invites you to send any written data, views, or arguments about this final rule. Send your comments to an address listed under ADDRESSES . Include “Docket No. FAA-2021-1175 and Project Identifier MCAI-2021-01409-G” at the beginning of your comments. The most helpful comments reference a specific portion of the final rule, explain the reason for any recommended change, and include supporting data. The FAA will consider all comments received by the closing date and may amend this final rule because of those comments.

Except for Confidential Business Information (CBI) as described in the following paragraph, and other information as described in 14 CFR 11.35, the FAA will post all comments received, without change, to https://www.regulations.gov,, including any personal information you provide. The agency will also post a report summarizing each substantive verbal contact received about this final rule.

Confidential Business Information

CBI is commercial or financial information that is both customarily and actually treated as private by its owner. Under the Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public disclosure. If your comments responsive to this AD contain commercial or financial information that is customarily treated as private, that you actually treat as private, and that is relevant or responsive to this AD, it is important that you clearly designate the submitted comments as CBI. Please mark each page of your submission containing CBI as “PROPIN.” The FAA will treat such marked submissions as confidential under the FOIA, and they will not be placed in the public docket of this AD. Submissions containing CBI should be sent to Jim Rutherford, Aviation Safety Engineer, FAA, General Aviation & Rotorcraft Section, International Validation Branch, 901 Locust, Room 301, Kansas City, MO 64106. Any commentary that the FAA receives which is not specifically designated as CBI will be placed in the public docket for this rulemaking.

Regulatory Flexibility Act

The requirements of the Regulatory Flexibility Act (RFA) do not apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt a rule without prior notice and comment. Because FAA has determined that it has good cause to adopt this rule without prior notice and comment, RFA analysis is not required.

Costs of Compliance

The FAA estimates that this AD affects 66 gliders of U.S. registry and estimates the following costs to comply with this AD:

Estimated Costs

Action	Labor cost	Parts cost	Cost per glider	Cost on U.S. operators
Remove freewheel clutch from service	4 work-hours × $85 per hour = $340	$500	$840	$55,440

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.

The FAA is 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

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, and

(2) Will not affect intrastate aviation in Alaska.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

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.

§ 39.13

[Amended]

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

2022-01-09 Stemme AG: Amendment 39-21897; Docket No. FAA-2021-1175; Project Identifier MCAI-2021-01409-G.

(a) Effective Date

This airworthiness directive (AD) is effective January 27, 2022.

(b) Affected ADs

None.

(c) Applicability

This AD applies to Stemme AG Model Stemme S 10-VT and Stemme S 12 gliders, all serial numbers, certificated in any category, with a freewheel clutch part number (P/N) 12AK with a serial number(S/N) starting with “12-” installed.

Note 1 to paragraph (c): Stemme Service Bulletin Doc. No. P062-980058, Revision 1, dated December 14, 2021, contains guidance for identifying the S/N of a P/N 12AK freewheel clutch.

(d) Subject

Joint Aircraft System Component (JASC) Code 7100, Powerplant System.

(e) Unsafe Condition

This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI identifies the unsafe condition as unintended slipping of the freewheel clutch with overheating (burnishing) of the friction pads inside of the clutch. The unsafe condition, if not addressed, could result in a loss of thrust and consequent loss of glider control.

(f) Required Action and Compliance

(1) Before further flight after the effective date of this AD, remove the freewheel clutch from service.

(2) As of the effective date of this AD, do not install a freewheel clutch P/N 12AK with an S/N starting with “12-” on any glider.

(g) Alternative Methods of Compliance (AMOCs)

(1) The Manager, International Validation Branch, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the certification office, send it to the attention of the person identified in paragraph (h)(1) of this AD and email to: [e-mail] .

(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.

(h) Related Information

(1) For more information about this AD, contact Jim Rutherford, Aviation Safety Engineer, General Aviation & Rotorcraft Section, International Validation Branch, FAA, 901 Locust, Room 301, Kansas City, MO 64106; phone: [phone]; fax: [phone]; email: [e-mail] .

(2) Refer to European Union Aviation Safety Agency (EASA) AD 2021-0278-E, dated December 15, 2021, for more information. You may examine the EASA AD in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-1175.

(3) For service information identified in this AD, contact Stemme AG, Flugplatzstrasse F2, Nr. 6-7, D-15344 Strausberg, Germany; phone: [phone]; fax: [phone]; email: [e-mail]; website: https://www.stemme.com . You may view this service information at the FAA, Airworthiness Products Section, Operational Safety Branch, 901 Locust, Kansas City, MO 64106. For information on the availability of this material at the FAA, call [phone].

(i) Material Incorporated by Reference

None.

Issued on January 4, 2022.

Lance T. Gant,

Director, Compliance & Airworthiness Division, Aircraft Certification Service.