81-19-07 BOEING: Amendment 39-4212. Applies to Boeing Model 727 airplanes certificated in all categories with the Air Flow Multiplier installed, through line number 1264, on which AiResearch Service Bulletin 21-2291 has not been incorporated. \n\n\tWithin 300 hours time-in-service after the effective date of this AD, accomplish one of the following, unless already accomplished: \n\n\tA.\tBegin performing the repetitive inspections of the Air Flow Multiplier in accordance with Boeing Alert Service Bulletin 727-21A95, dated May 29, 1981. This inspection must be repeated at intervals not to exceed 1000 hours time-in-service. Step B or C below may be used for terminating action for these repetitive inspections. \n\n\tB.\tAccomplish the modification to the air flow multiplier in accordance with AiResearch Service Bulletin 21-2291.\n \n\tC.\tAlternative inspections, repairs, or other action which provide an equivalent level of safety may be used when approved by the Chief, Seattle Area Aircraft Certification Office, FAA Northwest Region.\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 the above specified alert service bulletin from the manufacturer may obtain copies upon request to Boeing Commercial Airplane Company, P.O. Box 3707, Seattle, Washington 98124, or it may be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108. \n\n\tThis amendment becomes effective September 20, 1981.