80-08-02 BOEING: Amendment 39-3738. Applies to all Model 747 series airplanes certificated in all categories equipped with General Electric CF6 or Pratt and Whitney JT9D-3, - 7, engines. Compliance required within 300 landings after the effective date of this AD unless already accomplished. Inspect diagonal braces as follows: \n\n\tA.\tMeasure the outboard engine strut diagonal brace forward clevis root area wall thickness. If root wall thickness is 0.350 inch or greater, no further action is required. If the wall thickness is less than 0.350 inch, penetrant inspect the area for cracks, in accordance with Boeing Service Bulletin 747-54-2070. If cracks are found, prior to further flight replace brace or rework in accordance with paragraph B of this AD. \n\n\tB.\tParts cracked within the limits of paragraph III of Boeing Service Bulletin 747-54- 2070 may be reworked as noted therein. Parts with cracks exceeding these limits must be replaced or reworked in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region.\n\n\tC.\tUpon request of the operator, an FAA Principal Maintenance Inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA Northwest Region may adjust the compliance times if the request contains substantiating data to justify the increase for that operator. \n\n\tD.\tThis AD may be amended in the future to require a repeat inspection interval or terminating action.\n \n\tE.\tAircraft may be ferried to a base for maintenance in accordance with Section 21.197 and 21.199 of the Federal Aviation Regulations. The 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 may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108. \n\n\tThis amendment becomes effective April 17, 1980.