90-21-06: Engine Mount

90-21-06 DORNIER: Amendment 39-6755. Docket No. 90-CE-24-AD. Applicability: Models Do28D and Do28D-1 (all serial numbers) airplanes, certificated in any category. Compliance: Required as indicated in the body of the AD, unless already accomplished. To prevent engine mount failure, accomplish the following: (a) Within the next 50 hours time-in-service (TIS) after the effective date of this AD visually inspect the riveted connections between the L-section and formed sheet of the right-hand and left-hand engine mounts. (1) If no loose or damaged rivets are found, reinspect the connections at intervals of 100 hours TIS thereafter. (2) If any loose or damaged rivets are found, prior to further flight remove and replace any damaged rivets, and replace all universal and Huck blind rivets having a diameter of 3.2mm (.126 in) with steel blind rivets having a diameter of 4.0mm in accordance with the instructions contained in Dornier Service Bulletin No. 1131-1613, dated August 2, 1989. Reinspect the connections at intervals of 100 hours TIS thereafter. (b) Airplanes may be flown in accordance with FAR 21.197 to a location were this AD may be accomplished. (c) An alternate method of compliance or adjustment of the initial or repetitive compliance times, which provides an equivalent level of safety, may be approved by the Manager, Aircraft Certification Staff, Europe, Africa, and Middle East Office, FAA, c/o American Embassy, 1000 Brussels, Belgium. NOTE: The request should be forwarded through an FAA Maintenance Inspector, who may add comments and then send it to the Manager, Brussels Aircraft Certification Staff. All persons affected by this directive may obtain copies of the document referred to herein upon request to Dornier Luftfahrt GmbH, P.O. Box D-8031 Wessling, Federal Republic of Germany; or may examine this document at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri 64106. This amendment (39-6755, AD 90-21-06) becomes effective on November 13, 1990.