81-16-06 R1 McDONNELL DOUGLAS: Amendment 39-4177 as amended by Amendment 39-4234. Applies to McDonnell Douglas Model DC-10 series airplanes certificated in all categories. Compliance required within 10 days after the effective date of this AD. \n\n\tA.\tTo prevent temporary loss of all electrical flight instruments and lighting, incorporate in the Limitations Section of the FAA Approved Airplane Flight Manual a revision which specifies the following: \n\n\t\t1.\tPrior to each takeoff, stabilize engine RPM above 60% N2. With generators paralleled, check to ensure that generator frequency is below 420 Hz; or, if generators are nonparalleled, check to ensure that each operating generator is below 420 Hz. \n\n\t\t2.\tWhen operating at night or in instrument meteorological conditions, and before reaching 10,000 feet MSL during descent for landing, complete procedure to operate generators nonparalleled until landing. \n\n\tB.\tA copy of this AD inserted in the Airplane Flight Manual may be considered as an acceptable means of compliance with the required Airplane Flight Manual revision. \n\n\tC.\tAlternative means of compliance providing an equivalent level of safety may be used when approved by the Chief, Los Angeles Area Aircraft Certification Office, FAA Northwest Region. \n\n\tD.\tThe installation of new voltage sensing relay components in accordance with Group I, Phase I of Part 2, in the Accomplishment Instructions of McDonnell Douglas DC-10 Service Bulletin 24-116, dated August 21, 1981, or later revisions approved by the Chief, Los Angeles Area Aircraft Certification Office, FAA Northwest Region may be accomplished in lieu of the Flight Manual Revision and test procedure specified in paragraphs (A) and (B) above; and constitutes terminating action for this AD. \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). All persons affected by this directivewho have not already received these documents from the manufacturer may obtain copies upon request to the 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 FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108 or 4344 Donald Douglas Drive, Long Beach, California 90808. \n\n\tAmendment 39-4117 became effective August 10, 1981. \n\n\tThis amendment becomes effective October 26, 1981.