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Airworthiness Directives; Alexander Schleicher Model ASK-21 Sailplanes

AD 98-2780 Published 1998-02-05 1 model 43 US-registered tails affected Federal Register ↗

Abstract

This document proposes to adopt a new airworthiness directive (AD) that would apply to Alexander Schleicher Model ASK-21 sailplanes. The proposed action would require removing certain pages from the sailplane flight manual and replacing these pages with new pages having different information regarding spin and stall recovery. The proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by the proposed AD are intended to prevent operators from using inaccurate stall and spin recovery information provided in the sailplane flight manual (SFM), which, if not corrected, could result in the inability to recover from a spin or stall during flight.

Applicability

Aircraft makes and models this AD applies to, sorted by US-registered fleet size.

Federal Register text

Verbatim from the Federal Register publication — required actions, compliance times, parts/serial numbers, and methods of compliance. The Federal Register is the legally binding document; this rendering is for readability. Cite: 63 FR 5904.

[Federal Register Volume 63, Number 24 (Thursday, February 5, 1998)] [Proposed Rules] [Pages 5904-5905] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 98-2780]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-108-AD] RIN 2120-AA64

Airworthiness Directives; Alexander Schleicher Model ASK-21 Sailplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to adopt a new airworthiness directive (AD) that would apply to Alexander Schleicher Model ASK-21 sailplanes. The proposed action would require removing certain pages from the sailplane flight manual and replacing these pages with new pages having different information regarding spin and stall recovery. The proposed AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by the proposed AD are intended to prevent operators from using inaccurate stall and spin recovery information provided in the sailplane flight manual (SFM), which, if not corrected, could result in the inability to recover from a spin or stall during flight.

DATES: Comments must be received on or before March 3, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 97--CE-108--AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106. Comments may be inspected at this location between 8 a.m. and 4 p.m., Monday through Friday, holidays excepted. Service information that applies to the proposed AD may be obtained from Alexander Schleicher, Segelflugzeugbau, 6416 Poppenhausen, Wasserkuppe, Federal Republic of Germany; telephone 49.6658.890 or 49.6658.8920; facsimile: 49.6658.8923 or 49.6658.8940. This information also may be examined at the Rules Docket at the address above.

FOR FURTHER INFORMATION CONTACT: Mr. J. Mike Kiesov, Project Officer, Sailplanes/Gliders, Small Airplane Directorate, Aircraft Certification Service, FAA, 1201 Walnut, suite 900, Kansas City, Missouri 64106; telephone (816) 426-6932; facsimile (816) 426-2169.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket. Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: ``Comments to Docket No. 97--CE-108--AD.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, Central Region, Office of the Regional Counsel, Attention: Rules Docket No. 97--CE-108--AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Discussion

The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for the Federal Republic of Germany, recently notified the FAA that an unsafe condition may exist on Alexander Schleicher Model ASK-21 sailplanes. The LBA reports that the manufacturer's flight manual does not accurately document the stall and spin characteristics. The safety of the operator and the sailplane could be at risk when relying on the information contained in the SFM. The inaccuracy of the SFM, if not corrected, could result in the inability of the operator to recover from a stall or spin during flight.

Relevant Service Information

Alexander Schleicher has issued Technical Note No. 23, dated January 29, 1991, which specifies procedures for removing SFM pages 2, 22, 24, 33, and 34, and replacing these pages with new pages of the same numbers, but have a footnote ``TN 23 dated Jan 1991.'' The LBA classified this service bulletin as mandatory and issued AD 91-112 Schleicher, dated June 19, 1991, in order to assure the continued airworthiness of these sailplanes in Germany.

The FAA's Determination

The Alexander Schleicher Model ASK-21 sailplane model is manufactured in Germany and is 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. Pursuant to this bilateral airworthiness agreement, the LBA has kept the FAA informed of the situation described above. The FAA has examined the findings of the LBA, reviewed all available information, including the service information referenced above, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of the Provisions of the Proposed AD

Since an unsafe condition has been identified that is likely to exist or develop in other Alexander Schleicher Model ASK-21 sailplanes of the same type design registered in the United States, the proposed AD would require removing certain pages from the Alexander Schleicher Model ASK-21 SFM, and replacing them with new pages of the same numbers, dated January, 1991. Accomplishment of the proposed SFM change would be in accordance with the Action section of Alexander Schleicher Technical Note No. 23, dated January, 1991.

Cost Impact

The FAA estimates that 30 sailplanes in the U.S. registry would be affected by the proposed AD, that it would take approximately 1 workhour per sailplane to accomplish the proposed action, and that the average labor rate is approximately $60 an hour. The SFM pages are provided by the manufacturer at no cost to the owner/operator. Inserting the pages into the SFM may be performed by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the

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Federal Aviation Regulations (14 CFR 43.7), and must be entered into the aircraft records showing compliance with this AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9). Based on these figures, there is no cost impact of the proposed AD on U.S. owners/operators because the proposed action can be accomplished by the owner/operator.

Proposed Compliance Time

The proposed action, the LBA AD, and the Alexander Schleicher Technical Note No. 23, dated January 29, 1991, differ on the compliance time. The LBA AD and the Technical Note require that the replacement of the SFM pages be accomplished at the next annual inspection. The FAA is proposing a calendar compliance time instead of the next annual inspection because the service history on the U.S.-registered Schleicher Model ASK-21 sailplane does not warrant a need for immediate compliance, and because each sailplane has a different time for the next annual inspection. The calendar compliance will ensure that all of the sailplanes have changed the flight manual and be aware of the new information at approximately the same time.

Regulatory Impact

The regulations proposed herein would not have substantial direct effects 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. Therefore, in accordance with Executive Order 12612, it is determined that this proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this action (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) if promulgated, 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. A copy of the draft regulatory evaluation prepared for this action has been placed in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows:

Alexander Schleicher: Docket No. 97-CE-108-AD.

Applicability: Model ASK-21 sailplanes, serial numbers 21-001 through 21-205, certificated in any category.

Note 1: This AD applies to each sailplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For sailplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required within the next 3 calendar months after the effective date of this AD, unless already accomplished. To prevent operators from using inaccurate stall and spin recovery information provided in the sailplane flight manual (SFM), which, if not corrected, could result in the inability to recover from a spin or stall during flight, accomplish the following: (a) Remove pages 2, 22, 24, 33, and 34 from the Alexander Schleicher Model ASK-21 SFM, and replace these pages with new pages of the same numbers that have footnote ``TN 23 dated Jan 1991'', in accordance with Alexander Schleicher ASK 21 Technical Note No. 23, dated January 29, 1991. (b) Incorporating the SFM revisions, as required by this AD, may be performed by the owner/operator holding at least a private pilot certificate as authorized by section 43.7 of the Federal Aviation Regulations (14 CFR 43.7), and must be entered into the aircraft records showing compliance with this AD in accordance with section 43.9 of the Federal Aviation Regulations (14 CFR 43.9). (c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the sailplane to a location where the requirements of this AD can be accomplished. (d) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Small Airplane Directorate, Aircraft Certification Service, 1201 Walnut, suite 900, Kansas City, Missouri 64106. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Small Airplane Directorate.

Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Small Airplane Directorate.

(e) Questions or technical information related to Alexander Schleicher Technical Note No. 23, dated January 29, 1991, should be directed to Alexander Schleicher, Segelflugzeugbau, 6416 Poppenhausen, Wasserkuppe, Federal Republic of Germany; telephone 49.6658.890 or 49.6658.8920; facsimile: 49.6658.8923 or 49.6658.8940. This service information may be examined at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Note 3: The subject of this AD is addressed in German AD No. 91- 112 Schleicher, dated June 19, 1991.

Issued in Kansas City, Missouri, on January 29, 1998. Terry L. Chasteen, Acting Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 98-2780 Filed 2-4-98; 8:45 am] BILLING CODE 4910-13-U

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