AD 97-03-02

This amendment adopts a new airworthiness directive (AD) that applies to Glasflugel Models H301 "Libelle", H301B "Libelle", Standard "Libelle", Standard Libelle 201B, Club Libelle 205, and Kestrel sailplanes. This AD requires measuring and adjusting the control surface weight and static moment, and inserting amendments into the Glasflugel Flight and Service Manual. This AD results from reports of considerable variation of the weight and static moment of the control surface on the affected sailplanes found during repair or repainting of the control surface. The actions specified by this AD are intended to prevent sailplane flutter because the weight and static moment of the control surface are not within certain limits, which could result in flutter and subsequent loss of control of the sailplane.

Final rule

97-03-02 GLASFLUGEL: Amendment 39-9908; Docket No. 96-CE-38-AD.

Applicability: Models H301 "Libelle", H301B "Libelle", Standard "Libelle", Standard Libelle 201B, Club Libelle 205, and Kestrel sailplanes (all serial numbers), 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 (e) 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 addressit.

Compliance: Required within the next three calendar months after the effective date of this AD or at the time of any repair to or repainting of the control surface, whichever occurs first, unless already accomplished.

To prevent sailplane flutter because the weight and static moment of the control surface are not within certain limits, which could result loss of control of the sailplane, accomplish the following:

(a) Measure and adjust the control surface weight and static moment in accordance with the Glasflugel Flight and Service Manual amendments referenced in paragraph (b) of this AD.

(b) Insert the following amendments into the sailplane maintenance manual, as applicable:

Sailplane Models
Glasflugel Flight and Service Manual Amendment Page Numbers
H301 Libelle and
H301B Libelle
pages 14a and 14b
Standard Libelle
pages E14a and E14b
Standard Libelle 201B
pages E15a and E15b
Club Libelle 205
pages 42a and 42b
Kestrel
pages 27a and 27b

(c)Inserting the amendments into the Glasflugel Flight and Service Manual as required by paragraph (b) of 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 43.11 of the Federal Aviation Regulations (14 CFR 43.11).

(d) 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.

(e) 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 MaintenanceInspector, 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.

(f) The inspections required by this AD shall be done in accordance with the following Glasflugel Flight and Service Manual amendments, as applicable:

Sailplane Models
Glasflugel Flight and Service Manual Amendment
Page Numbers

Manual Date
H301 Libelle and
H301B Libelle
pages 14a and 14b
May 1965
Standard Libelle
pages E14a and E14b
October 1968
Standard Libelle 201B
pages E15a and E15b
July 1972
Club Libelle 205
pages 42a and 42b
October 1974
Kestrel
pages 27a and 27b
April 1971

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 Glasflugel, c/o Hr. H. Streifeneder, Glasfaser-Flugzeug-Service GmbH, Hofener Weg, D-72582 Grabenstetten, Germany. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief 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.

(g) This amendment becomes effective on March 21, 1997.

Events Leading to 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 Glasflugel Models H301 "Libelle", H301B "Libelle", Standard "Libelle", Standard Libelle 201B, Club Libelle 205, and Kestrel sailplanes was published in the Federal Register on October 15, 1996 (61 FR 53683). The action proposed to require measuring and adjusting the control surface weight and static moment, and inserting the following amendments into the Glasflugel Flight and Service Manual, as applicable:

Sailplane Models
Glasflugel Flight and Service Manual Amendment Page Numbers
H301 Libelle and
H301B Libelle
pages 14a and 14b
Standard Libelle
pages E14a and E14b
Standard Libelle 201B
pages E15a and E15b
Club Libelle 205
pages 42a and 42b
Kestrel
pages 27a and 27b

Accomplishment of the proposed action as specified in the notice of proposed rulemaking (NPRM) would be in accordance withthe instructions in the above-referenced Glasflugel Flight and Service Manual amendments.

The NPRM resulted from reports of considerable variation of the weight and static moment of the control surface on the affected sailplanes found during repair or repainting of the control surface.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were received on the proposed AD 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.

Compliance Time of This AD
The compliance time for this ADis presented in calendar time and whenever the control surface is repaired or repainted (the prevalent one being that which occurs first). The FAA has determined that a calendar time for compliance is desirable because the unsafe condition described by this AD is not directly related to sailplane operation. The control surface weight and static moment could become outside the specified limits after repair or repainting instead of occurring during normal operation of the sailplane. Also, if the sailplane control surface is already scheduled for repair or repainting, then accomplishing this action at the time of repair or repainting will not force the owner/operator to schedule this action at a later time and will allow the action to be accomplished during already-scheduled maintenance.

Cost Impact
The FAA estimates that 174 sailplanes in the U.S. registry will be affected by this AD, that it will take approximately 1 workhour per sailplane to accomplish the required action, andthat the average labor rate is approximately $60 an hour. Material to accomplish the surface control weight and static moment balance costs approximately $10 per sailplane. Based on these figures, the total cost impact of the AD on U.S. operators is estimated to be $12,180. This figure only takes into account the one-time measurement and adjustment of the control surface weight and static moment; it does not reflect the time it would take an owner/operator of an affected sailplane to insert the amendments into the Glasflugel Flight and Service Manual.

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 preparationof 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 USC 106(g), 40113, 44701.

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