AD 86-15-05

86-15-05 DEHAVILLAND AIRCRAFT OF CANADA, LTD.: Amendment 39-5357. Applies to Model DHC-7 airplanes, serial numbers 1 through 14 inclusive, certificated in any category. Compliance is required within 60 days after the effective date of this AD, unless previously accomplished. To assure proper crew warning in the event of the loss of the 400 Hz AC electrical power system, accomplish the following:

1. Modify the 400 Hz AC system in accordance with DeHavilland Service Bulletin 7-24-13, Revision A, dated September 10, 1982.

2. 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, Standardization Branch, ANM-113, FAA, Northwest Mountain Region.

3. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD.

All persons affected by this directive, who have not already received the appropriate service bulletin from the manufacturer, may obtain copies upon request to DeHavilland Aircraft of Canada, Ltd., Downsview, Ontario M3K 1Y5, Canada. This document may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Seattle Aircraft Certification Office, 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective September 4, 1986.