82-04-06 MCDONNELL DOUGLAS: Amendment 39-4320. Applies to McDonnell Douglas Model DC-10-40 airplanes equipped with Pratt and Whitney JT9D-20 series engines, certificated in all categories. Compliance required within twelve (12) calendar months from the effective date of this AD, unless already accomplished. \n\n\tTo minimize the possibility of separation of the nose cowl from the aircraft in the event of fan blade failure, accomplish the following: \n\n\tA.\tReplace the nose cowl attaching bolts and nuts on engines 1 and 3 as outlined in the Accomplishment Instructions and Material Information in McDonnell Douglas DC-10 Service Bulletin 71-123 dated June 23, 1981, or later revisions approved by the Chief, Los Angeles Area Aircraft Certification Office, FAA Northwest Mountain Region. \n\n\tB.\tAlternate means of compliance with this AD which provide an equivalent level of safety may be used when approved by the Chief, Los Angeles Area Aircraft Certification Office, FAA Northwest Mountain 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 these documents from the manufacturer may obtain copies upon request to: McDonnell Douglas Corporation, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Director, Publications and Training, C1-750 (54-60). These documents also may be examined at the FAA Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington 98108, or 4344 Donald Douglas Drive, Long Beach, California 90808. \n\n\tThis amendment becomes effective March 4, 1982.