80-21-01 MCDONNELL DOUGLAS: Amendment 39-3933. Applies to DC-10 Series Airplanes fuselage numbers 1 through 243. \n\n\tCompliance required as indicated, unless already accomplished. To prevent restriction of travel of the wing and tail engine fuel shutoff valve, thereby adversely affecting operation of the engine emergency fire shutoff handles and loss of associated fire fighting safeguards, accomplish the following: \n\n\t(a)\tWithin 300 hours additional time in service after the effective date of this AD replace P/N AA 2603 type cable guard pins in accordance with McDonnell Douglas Alert Service Bulletin A76-28 as dated September 8, 1980. \n\n\t(b)\tSpecial flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of the modifications required by this AD. \n\n\t(c)\tAlternative inspections, modifications or other actions which provide an equivalent level of safety may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region. \n\n\tThis amendment becomes effective October 13, 1980.