89-12-07 BOEING: Amendment 39-6232. \n\tApplicability: All Model 747 series airplanes, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo prevent reduced lateral control caused by icing of the aileron control cables, accomplish the following: \n\n\tA.\tWithin the next 15 months after the effective date of this AD, unless already accomplished within the last 3 months, and thereafter at intervals not to exceed 18 months, perform the following: \n\n\t\t1.\tGain access to the cavity aft of the wing center section. \n\t\t2.\tRemove all debris and foreign material, clean the cavity, and verify all drains are open and clean. \n\n\tB.\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, Northwest Mountain Region. \n\n\tNOTE: The request should be forwarded through an FAA Principal MaintenanceInspector (PMI), who may add any comments and then send it to the Manager, Seattle Aircraft Certification Office. \n\n\tC.\tSpecial flight permits may be 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 FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, FAA, Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington. \n\n\tThis amendment (39-6232, AD 89-12-07) becomes effective on July 10, 1989.