AD 99-03-01

This amendment adopts a new airworthiness directive (AD) that applies to certain Schempp-Hirth K.G. (Schempp-Hirth) Models Standard-Cirrus, Nimbus-2, JANUS, and Mini-Nimbus HS-7 sailplanes. This AD requires installing a safety device for the tailplane locking hook. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany. The actions specified by this AD are intended to prevent the locking hook on the tailplane attachment bracket from disengaging, which could result in the horizontal tailplane coming loose from the fin with possible loss of longitudinal control of the sailplane.

Final rule

99-03-01 SCHEMPP-HIRTH K.G.: Amendment 39-11013; Docket No. 98-CE-52-AD.
Applicability: The following sailplane models and serial numbers, certificated in any category:

Models
Serial Numbers
Standard Cirrus
573, 586, 593, 595, 597 through 599, 601 through
701
Nimbus-2
86, 93, and 96 through 116, 118 through 129, 131,
and 176
JANUS
1 through 55, and 59
Mini-Nimbus HS-7
1 through 60, and 65

NOTE 1: Both Schempp-Hirth Technical Note No. 278-36, 286-33, 295-26, 328-11, 798-3, dated November 11, 1994, and German AD 95-015, dated December 15, 1994, apply to the Model Nimbus-2M sailplanes. This sailplane model is not type certificated for operation in the United States, and therefore is not covered by the applicability of this AD. The Model Nimbus-2M sailplanes could be operating in the United States with an experimental certificate. The FAA recommends that any person operating a Model Nimbus-2M sailplane in the United States with an experimental certificate accomplish the actions specified in the technical note.

NOTE 2: 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 6 calendar months after the effective date of this AD, unless already accomplished.

To prevent the locking hook on the tailplane attachment bracket from disengaging, which could result in the horizontal tailplane coming loose from the fin with possible loss of longitudinal control of the sailplane, accomplish the following:

(a) Install a safety device for the tailplane locking hook in accordance with Schempp-Hirth Appendix to Technical Note No. 278-36, 286-33, 295-26, 328-11, 798-3, dated November 11, 1994.

(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 3: 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 the service information referenced in this document should be directed to Schempp-Hirth Flugzeugbau GmbH, Postbox 14 43, D-73222 Kirchheim unter Teck, Federal Republic of Germany. 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.

(e) The installation required by this AD shall be done in accordance with Schempp-Hirth Appendix to Technical Note No. 278-36, 286-33, 295-26, 328-11, 798-3, dated November 11, 1994. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Schempp-Hirth Flugzeugbau GmbH, Postbox 14 43, D-73222 Kirchheim unter Teck, Federal Republic of Germany. Copies may be inspected at the FAA, Central Region, Office of the Regional Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC.

NOTE 4: The subject of this AD is addressed in German AD 95-015, dated December 15, 1994.

(f) This amendment becomes effective on March 12, 1999.

Events Leading to the Issuance of This AD
A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an AD that would apply to certain Schempp-Hirth Models Standard-Cirrus, Nimbus-2, JANUS, and Mini-Nimbus HS-7 sailplanes was published in the Federal Register as a supplemental notice of proposed rulemaking (NPRM) on November 9, 1998 (63 FR 60224). The supplemental NPRM proposed to require installing a safety device for the tailplane locking hook. Accomplishment of the proposed action as specified in the supplemental NPRM would be in accordance with Schempp- Hirth Appendix to Technical Note No. 278-36, 286-33, 295-26, 328-11, 798-3, dated November 11, 1994.

The NPRM was the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for Germany.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed rule or the FAA's determination of the cost to the public.

The FAA's Determination
After careful review of all available information related to the subject presented above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed except for minor editorial corrections. The FAA has determined that these minor corrections will not change the meaning of the AD and will not add any additional burden upon the public than was already proposed.

Cost Impact
The FAA estimates that 91 sailplanes in the U.S. registry will be affected by this AD, that it will take approximately 3 workhours per sailplane to accomplish this action, and that the average labor rate is approximately $60 an hour. Parts cost approximately $35 per sailplane. Based on these figures, the total cost impact of this AD on U.S. operators is estimated to be $19,565, or $215 per sailplane.

Compliance Time of This AD
Although the unsafe condition identified in this AD occurs during flight and is a direct result of sailplane operation, the FAA has no way of determining how much time will elapse before the tailplane is not securely attached to the fin. For example, the condition could exist on a sailplane with 200 hours time-in-service (TIS), but could be developing on a sailplane with 50 hours TIS and not actually exist on this sailplane until 300 hours TIS. For this reason, the FAA has determined that a compliance based on calendar time should be utilized in this AD in order to assure that the unsafe condition is addressed on all sailplanes in a reasonable time period.

Differences Between the Technical Note, German AD, and This AD
Both Schempp-Hirth Technical Note No. 278-36, 286-33, 295-26, 328-11, 798-3, dated November 11, 1994, and German AD 95-015, dated December 15, 1994, apply to the Model Nimbus-2M sailplanes. This sailplane model is not type certificated for operation in the United States and thereforeis not covered by the applicability of this AD.

The Model Nimbus-2M sailplanes could be operating in the United States with an experimental certificate. The FAA is including a NOTE in this AD to recommend that any person operating a Model Nimbus-2M sailplane in the United States with an experimental certificate accomplish the actions specified in the technical note.

Regulatory Impact
The regulations adopted herein will 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 final rule does 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) 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 final evaluation prepared for this action is contained 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, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to 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. Section 39.13 is amended by adding a new airworthiness directive (AD) to read as follows: