91-11-03 MCDONNELL DOUGLAS: Amendment 39-6999. Docket No. 90-NM-287-AD. Supersedes AD 90-22-05. \n\n\tApplicability: Model DC-9-80 (MD-80) series airplanes and Model MD-88 airplanes, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo prevent passenger service unit (PSU) oxygen doors from being jammed closed, accomplish the following: \n\n\tA.\tWithin 45 days after November 5, 1990 (the effective date of Amendment 39- 6780, AD 90-22-05), and thereafter at intervals not to exceed 45 days, inspect all PSU oxygen doors for proper closure, in accordance with McDonnell Douglas Alert Service Bulletin A25-315, Revision 1, dated August 24, 1990. \n\n\tB.\tAny jammed PSU oxygen doors found during the inspection required by paragraph A. of this AD must be readjusted prior to further flight, in accordance with Phase I of paragraph 2 of the Accomplishment Instructions of McDonnell Douglas Alert Service Bulletin A25-315, Revision 1, datedAugust 24, 1990. \n\n\tC.\tWithin 12 months after the effective date of this AD install PSU oxygen door stops in accordance with Phase II of paragraph 2 of the Accomplishment Instructions of McDonnell Douglas Alert Service Bulletin A25-315, Revision 1, dated August 24, 1990. Such installation constitutes terminating action for the repetitive inspections required by paragraph A. of this AD. \n\n\tD.\tAn alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. \n\n\tNOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Los Angeles ACO. \n\n\tNOTE: Previously granted approval for an alternative method of compliance to AD 90- 22-05 also constitutes approval for this AD. \n\n\tE.\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 McDonnell Douglas Corporation, Post Office Box 1771, Long Beach, California 90801, Attn: Business Unit Manager, Technical Publications, C1-HCW (54-60). These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington, or the Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California. \n\n\tThis amendment supersedes Amendment 39-6780, AD 90-22-05. \n\n\tThis amendment (39-6999, AD 91-11-03) becomes effective on June 24, 1991.