90-09-51 BOEING: Amendment 39-6659. Docket No. 90-NM-72-AD. Final copy of telegraphic AD T90-09-51, issued April 19, 1990.\n \n\tApplicability: All model 767 series airplanes, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo prevent unacceptable asymmetric slat deployment, accomplish the following: \n\n\tA.\tWithin the next 20 days after the effective date of this AD, conduct a one-time inspection of the leading edge slat drive mechanism to check for torque tube damage, check for proper coupling installation, and ensure that screws on the couplings are in place and lockwired. Perform this inspection in accordance with Part I of Boeing Alert Service Bulletin 767-27A0095, Revision 1, dated February 22, 1990. \n\n\tB.\tRepair all discrepancies that are revealed by the inspection required by paragraph A., above, prior to further flight, in accordance with Boeing Alert Service Bulletin 767-27A0095, Revision 1, dated February 22, 1990. \n\n\tC.\tWithin 10 days after the completion of the inspection required by paragraph A., above, submit a report of findings of discrepancies in the leading edge slat drive mechanism to the Manager, Seattle Aircraft Certification Office, ANM-100S, 17900 Pacific Highway South, C- 68966, Seattle, Washington 98168. Reports must include a description of the defective parts, their location with regard to the drive system, the airplane serial number, and the total flight hours and flight cycles on that airplane. \n\n\tD.\tAn alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Transport Airplane Directorate. \n\n\tNote: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, Seattle Aircraft Certification Office. \n\n\tE.\tSpecial flight permits maybe issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD. \n\n\tAll persons affected by this directive who have not already received the appropriate service documents from the manufacturer, may obtain copies upon request to Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington. \n\n\tThis amendment (39-6659, AD 90-09-51) becomes effective on July 31, 1990, as to all persons, except those persons to whom it was made immediately effective by telegraphic AD T90-09-51, issued April 19, 1990, which contained this amendment.