83-24-09 DeHAVILLAND AIRCRAFT OF CANADA, LTD.: Amendment 39-4781. Applies to DeHavilland Model DHC-7 airplanes, Serial Numbers 3 through 92 inclusive.
Compliance is required within the next 750 flight hours or three months after effective date of this AD, whichever occurs first, unless previously accomplished. To protect against loss of trimability and partial loss of pitch control, accomplish the following:
1. Incorporate Modification Number 7/2209 on each elevator and Modification Numbers 7/2211 and 7/2216 on the tailplane in accordance with instruction contained in DeHavilland Service Bulletin No. 7-55-6, Rev. B, dated September 17, 1982.
2. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, 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 as required by this AD.
This amendment becomes effective December 21, 1983.