AD 81-14-09

81-14-09 ROCKWELL INTERNATIONAL: Amendment 39-4157. Applies to Models NA-265-40, Serial Numbers 282-1 through 282-97, and NA-265-60, Serial Numbers 306-1 through 306-63, airplanes certificated in any category not modified in accordance with life extension modifications per North American Rockwell Drawing No. 306-053010.

COMPLIANCE: Required as indicated unless already accomplished.

To prevent inadvertent cabin depressurization, accomplish the following:

A) On aircraft with 2,000 or more hours total time-in-service as of the effective date of this AD, within the next 600 hours additional time-in-service or within the next 12 months, whichever occurs first:

1. Conduct a dye penetrant inspection of the door stop (beam) in accordance with the Inspection Instructions of Sabreliner Service Bulletin No. 55 dated March 31, 1980, as revised June 16, 1980.

2. If no cracks are detected, repeat the inspection at intervals not to exceed 600 hours time-in-service or 1year, whichever occurs first.

3. If cracks are detected, replace the cracked part with a new part and after an additional 2,000 hours aircraft time-in-service, resume inspections at 600 hour time-in-service intervals, or modify the aircraft in accordance with Sabreliner Service Bulletin No. 3, dated December 19, 1975, as revised August 4, 1978. Installation of the applicable kit in accordance with Sabreliner Service Bulletin No. 3 eliminates the inspection requirement of this AD.

B) On aircraft with less than 2,000 hours total time-in-service as of the effective date of this AD, prior to accumulating 2,600 hours time-in-service or within the next 12 months from the time the aircraft has accumulated 2,000 hours time-in-service, whichever occurs first, accomplish the inspection and corrective action specified in Paragraph A) as applicable.

C) Aircraft may be flown in accordance with FAR 21.197 to a location where this AD may be accomplished.

D) Any equivalent methodof compliance with this AD must be approved by the Chief, Aircraft Certification Program, Room 238, Terminal Building 2299, Mid-Continent Airport, Wichita, Kansas 67209; telephone (316) 942-4285.

E) Record compliance with this AD by an appropriate entry in the airplane maintenance records. This should include those airplanes where the provisions of this AD have already been accomplished.

This Amendment becomes effective July 13, 1981.