AD 91-15-07

91-15-07 SCHEMPP-HIRTH: Amendment 39-7070. Docket No. 91-CE-17-AD.

Applicability: Cirrus and Cirrus VTC sailplanes (serial numbers 1 through 183, with or without a Y suffix), certificated in any category.

Compliance: Required within the next 30 calendar days after the effective date of this AD, unless already accomplished.

To prevent tail flutter that could result in complete loss of control of the sailplane, accomplish the following:

(a) Replace the 8mm diameter drive tube on the elevator drive lever with a round bar in accordance with drawing Cirrus No. 30.011/1 - Elevator Drive Axle of Schempp-Hirth Technical Note No. 265-6, dated April 27, 1982.

(b) Determine the elevator hinge moments and weights using the criteria on page 27 of the Cirrus service manual. If the moments and weights exceed the published criteria, prior to further flight, accomplish the following:

(1) Remove the tail parachute from operation and perform the requirements in Action 3, a) through d), of Schempp-Hirth Technical Note No. 265-6, dated April 27, 1982.

(2) Install a mass balance on the elevator in accordance with drawing Cirrus No. 30.001/1 - Elevator mass balance of Schempp-Hirth Technical Note No. 265-6, dated April 27, 1982.

NOTE: Although not required by this AD, the pages referenced by Action 3 e) and Action 5 of Schempp-Hirth Technical Note No. 265-6, dated April 27, 1982, should be incorporated into the service manual.

(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, Brussels Aircraft Certification Office, Europe, Africa, Middle East office, FAA, c/o American Embassy, 1000 Brussels, Belgium. The request should be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Brussels Aircraft Certification Office.

(d) The inspections and replacements required by this AD shall be done in accordance with Schempp-Hirth Technical Note No. 265-6, dated April 27, 1982, which incorporates the following pages:

Pages Revision Level Date 1 through 4 Original April 27, 1982 Cirrus No. 30.001/1, as referenced on page 2 of Technical Note 265-6. Attachment Undated Cirrus No. 30.011/1, as referenced on page 1 of Technical Note 265-6. Attachment Undated Page 27 of the Schempp-Hirth Cirrus Service Manual Attachment April 27, 1982 (The attachments listed in the above table are sent by the manufacturer as part of Technical Note 265-6). 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, Postfach 1443, D-7312 Kirchheim, Federal Republic of 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, 1100 L Street, NW, Room 8401, Washington, DC.

This amendment (39-7070, AD 91-15-07) becomes effective on September 1, 1991.