84-21-01 R1 BRITISH AEROSPACE: Amendment 39-4932 as amended by Amendment 39- 4993. Applies to all Model DH/HS/BH 125 series airplanes certificated in all categories, with the serial numbers specified in the service bulletins listed below. Compliance is required as indicated. To prevent electrical failures in the 'ZL' panel, accomplish the following within the next 90 days after the effective date of this AD unless previously accomplished:
A. Replace the two existing 80 amp fuses on the 'ZL' panel with 100 amp fuses, in accordance with the Accomplishment Instructions of British Aerospace 125 Aircraft Service Bulletin 24-239-(2885), Revision 1, dated February 27, 1984.
B. Install covers on the 'ZL' panel as follows:
1. For aircraft that have accomplished STC SA3870WE or STC SA3925WE, in accordance with the Accomplishment Instructions of AiResearch Aviation Company Service Bulletin No. 6-7, dated October 25, 1983.
2. For any other aircraft fitted with Garrett TFE 731-3 engines, in accordance with the Accomplishment Instructions of British Aerospace 125 Aircraft Service Bulletin 24-220-(2749), Revision 3, dated March 3, 1983.
C. 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.
D. 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.
Amendment 39-4932 became effective November 14, 1984.
This Amendment 39-4993 becomes effective February 11, 1985.