AD 90-11-10

90-11-10 BOEING: Amendment 39-6608. Docket No. 89-NM-144-AD.

Applicability: Model 757 and 767 series airplanes, equipped with Collins flight control computers (FCC), certified in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent intermittent altitude hold, altitude capture, and/or flight director mistracking anomalies, accomplish the following:

A. Within the next 24 months after the effective date of this AD, remove Collins manufactured FCC's which have Boeing P/N S241T100-103, and replace with units reworked to P/N S241T100-108, in accordance with Collins Service Bulletins FCC-701-22-10, Revision 2, dated March 24, 1988, and FCC-701-22-16, dated October 14, 1988.

B. Within the next 12 months after the effective date of this AD, remove Collins manufactured FCC's which have Boeing P/N S241T100-105 or -106, and replace with units reworked to P/N S241T100-108, in accordance with Collins Service Bulletin FCC-701-22-16, dated October 14, 1988.

C. Alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.

NOTE: The request should be forwarded through an FAA Principal Avionics Inspector, who will either concur or comment and then send it to the Manager, Seattle Aircraft Certification Office.

D. Special 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. All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle,Washington, or Seattle Aircraft Certification Office, FAA, Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington.

This amendment (39-6608, AD 90-11-10) becomes effective on July 2, 1990.