86-20-05 BOEING: Amendment 39-5426. Applies to Boeing Model 707-300 series airplanes modified in accordance with Supplemental Type Certificate (STC) SA2699NM, certificated in any category. Compliance required as indicated, unless previously accomplished. \n\n\tTo prevent loss of engine core cowl door, within 150 hours time in service, or within 30 days, whichever occurs earlier after the effective date of this AD, accomplish the following: \n\n\tA.\tModify the core cowl doors and pylon support brackets in accordance with Tracor Aviation Alert Service Bulletins AQ707-71-006, Revision 1, dated February 18, 1986; AQ707-71-012, Revision 1, dated September 5, 1986; AQ707-71-013, dated September 4, 1986; and Tracor Aviation Service Bulletins Q707-71-007, dated March 7, 1986; Q707-71-009, Revision 1, dated July 9, 1986; Q707-71-010, dated May 30, 1986; or later FAA-approved revisions. \n\n\tB.\tAlternate means of compliance which provide an acceptable level of safety may be used when approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region. \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 Tracor Aviation, Inc., 495 South Fairview Avenue, Goleta, California 93117, Attention: Customer Services. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Los Angeles Aircraft Certification Office, 4344 Donald Douglas Drive, Long Beach, California. \n\n\tThis amendment becomes effective October 13, 1986.