80-20-02 BOEING: Amendment 39-3928. Applies to all Boeing Model 747 airplanes which are equipped with B.F. Goodrich slides or turbofans identified in B.F. Goodrich Service Bulletin 25-060 dated July 14, 1980. \n\n\tNOTE: Boeing Service Bulletin 747-25-2543 dated September 5, 1980, lists the airplanes originally delivered with the affected slides. These slides may be on airplanes not listed in this service bulletin.\n \n\tCompliance is required as indicated. Accomplish the following: \n\n\tA.\tWithin 30 days from the effective date of this AD, unless already accomplished, replace the flapper valves in affected B.F. Goodrich slides installed on the upper deck of any Model 747-200F and 747-200C airplanes carrying passengers on the upper deck only. Install flapper valves in accordance with B.F. Goodrich Service Bulletin 25-060 dated July 14, 1980, or later FAA approved revisions or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. \n\n\tB.\tPrior to January 1, 1981, replace the flapper valves in all remaining B.F. Goodrich slides and turbofans in accordance with B.F. Goodrich Service Bulletin 25-060 dated July 14, 1980, or later FAA approved revisions or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region.\n \n\tC.\tUpon request of the operator, an FAA Maintenance Inspector, subject to prior approval by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region may adjust the compliance times if the request contains substantiating data to justify the changes. \n\n\tThe manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). \n\n\tAll persons affected by this directive who have not already received these documents from the manufacturer, may obtain copies upon request to Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124. These documents mayalso be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108. \n\n\tThis amendment becomes effective October 7, 1980.