Airworthiness Directives; Alexander Schleicher Segelflugzeugbau Model ASK-21 Sailplanes

[Federal Register Volume 62, Number 244 (Friday, December 19, 1997)] [Proposed Rules] [Pages 66560-66561] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 97-33144]

======================================================================== Proposed Rules Federal Register ________________________________________________________________________ This section of the FEDERAL REGISTER contains notices to the public of the proposed issuance of rules and regulations. The purpose of these notices is to give interested persons an opportunity to participate in the rule making prior to the adoption of the final rules. ========================================================================

Federal Register / Vol. 62, No. 244 / Friday, December 19, 1997 / Proposed Rules

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-CE-107-AD] RIN 2120-AA64

Airworthiness Directives; Alexander Schleicher Segelflugzeugbau 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 certain Alexander Schleicher Segelflugzeugbau (Alexander Schleicher) Model ASK-21 sailplanes. The proposed AD would require replacing any tow release cable assembly that does not have a swivel-type end with a cable assembly that does have a swivel-type end. 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 the inability to release the tow rope because of the design of the cable assembly, which could result in loss of control of the sailplane during towing operations.

DATES: Comments must be received on or before January 19, 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-107-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-107-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-107-AD, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106.

Discussion

The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, notified the FAA that an unsafe condition may exist on certain Alexander Schleicher Model ASK-21 sailplanes. The LBA reports that service difficulty reports indicate that the tow release cable creates loops over time. The loops are relatively short and lead to strong bending loads on the cable, mainly at the binding clamp. The original design of the tow release cable does not consist of a swivel- type end. This condition, if not corrected, could result in the inability to release the tow rope with consequent loss of control of the sailplane during towing operations.

Relevant Service Information

Alexander Schleicher has issued Technical Note No. 10, dated October 10, 1983, which specifies procedures for replacing any tow release cable assembly that does not have a swivel-type end with a tow release cable assembly that does have a swivel-type end. The LBA classified this service bulletin as mandatory and issued German AD No. 84-2, dated January 13, 1984, in order to assure the continued airworthiness of these sailplanes in Germany.

The FAA's Determination

This sailplane model is manufactured in Germany and is type certificated for operation in the United States under the provisions of Sec. 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

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States, the FAA is proposing AD action. The proposed AD would require replacing any tow release cable assembly that does not have a swivel- type end with a tow release cable assembly that does have a swivel-type end. Accomplishment of the proposed installation would be in accordance with the technical note previously referenced.

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 2 workhours per sailplane to accomplish the proposed replacement, and that the average labor rate is approximately $60 an hour. Parts cost approximately $20 per sailplane. Based on these figures, the total cost impact of the proposed AD on U.S. operators is estimated to be $4,200, or $140 per sailplane.

Compliance Time of the Proposed AD

Although the loops that form in the cable assembly would only occur during flight over time and the bending loads are related to sailplane operation, the FAA has no basis to determine the approximate number of hours time-in-service (TIS) when the unsafe condition is likely to occur. For example, the loops could form in the tow release cable assembly on a sailplane with 10 hours TIS, but not form until 500 hours TIS on another sailplane. For this reason, the FAA has determined that a compliance based on calendar time should be utilized in the proposed AD in order to assure that the unsafe condition is addressed on all sailplanes in a reasonable time period.

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 Segelflugzeugbau: Docket No. 97-CE-107-AD.

Applicability: Model ASK-21 sailplanes, serial numbers 21-001 through 21-196, certificated in any category, that are equipped with a tow release cable assembly that does not have a swivel-type end.

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 (c) 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 the inability to release the tow rope because of the design of the cable assembly, which could result in loss of control of the sailplane during towing operations, accomplish the following: (a) Replace any tow release cable assembly that does not have a swivel-type end with a tow release cable assembly that does have a swivel-type end in accordance with Alexander Schleicher Technical Note No. 10, dated October 10, 1983. (b) 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. (c) 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, FAA, 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. (d) Questions or technical information related to Alexander Schleicher Technical Note No. 10, dated October 10, 1983, 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.

Note 3: The subject of this AD is addressed in German AD No. 84- 2, dated January 13, 1984.

Issued in Kansas City, Missouri, on December 11, 1997. Michael Gallagher, Manager, Small Airplane Directorate, Aircraft Certification Service. [FR Doc. 97-33144 Filed 12-18-97; 8:45 am] BILLING CODE 4910-13-U