AD 90-08-05

90-08-05 BOEING OF CANADA, LTD., DE HAVILLAND DIVISION: Amendment 39- 6561. Docket No. 89-NM-227-AD.

Applicability: De Havilland Model DHC-8 series airplanes, Serial Numbers 1 through 179, certificated in any category.

Compliance: Required within 12 months after the effective date of this AD, unless previously accomplished.

To ensure the proper operation of the emergency lighting system when required, accomplish the following:

A. Relocate the emergency lights circuit breaker on the circuit breaker panel from the right essential bus to the right secondary bus and terminate a wire, in accordance with the Accomplishment Instructions of de Havilland Service Bulletin No. 8-33-17, dated August 25, 1989.

B. An 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, New York Aircraft Certification Office, ANE-170, FAA, New England Region.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who will either concur or comment and then send it to the Manager, New York Aircraft Certification Office, ANE-170.

C. 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 of Canada, Ltd., de Havilland Division, Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 17900 Pacific Highway South, Seattle, Washington, or at the FAA, New England Region, New York Aircraft Certification Office, 181 South Franklin Avenue, Room 202, Valley Stream, New York.

This amendment (39-6561, AD 90-08-05) becomes effective on May 4, 1990.