72-21-02 BRANTLY: Amdt. 39-1534 as amended by Amendment 39-1569. Applies to Model B-2, B-2A and B-2B Helicopters certificated in all categories.
Compliance required as indicated, unless already accomplished:
To prevent fatigue failure of the pylon outboard bearing shaft, Part Number 280-5 or 280- 6, replace these parts (three per helicopter) with serviceable parts having Part Number 280-6 within the next 10 hours time in service after the effective date of this AD, or upon the accumulation of 500 hours total time in service, whichever occurs later. The replacement pylon outboard bearing shafts must be torqued to 2500 plus or minus 100 inch-pounds and secured with an AN435-4-9 rivet or equivalent.
This AD effectively revises the service life limits published in Type Certificate Data Sheet No. 2H2 for Part Numbers 280-5 and 280-6, which are a part of the hub and inboard blade assembly Part Number 305-1. Part Numbers 280-5 and 280-6 pylon outboard bearing shafts, willnow have a service life limit of 500 hours time in service.
Type Certificate Holder, Mr. M. K. Hynes, 1241 Lake Horney Drive, Lakeland, Florida, 33801, may be contacted for information regarding installation tools, replacement parts, etc.
Amendment 39-1534 became effective October 14, 1972, for all persons except those to whom it was made effective upon receipt of the air mail letter dated October 3, 1972, which contained this amendment.
This Amendment 39-1569 becomes effective on December 8, 1972