64-06-04 HUGHES: Amdt. 706 Part 507 Federal Register March 18, 1964. Applies to Model 269A Helicopters, Serial Numbers 0011 to 0314 Inclusive, Model 269A-1 Helicopters, Serial Numbers 0001 to 0007 Inclusive, and Model 269B Helicopters, Serial Numbers 0001 to 0079 Inclusive.
Compliance required as indicated.
As a result of several recent failures of the lower coupling drive shaft (Hughes P/N 269A5504) accomplish the following:
(a) Within 25 hours' time in service after the effective date of this AD, unless already accomplished within the last 75 hours' time in service, and every 100 hours' time in service thereafter from the last inspection until accomplishment of (b), remove the lower coupling drive shaft and conduct a dye penetrant or magnetic particle inspection of the shaft. Pay particular attention to the radii at the end splines, alinement collar and boot mounting collar. Replace any shaft exhibiting evidence of cracking before further flight.
(b) Within500 hours' time in service after the effective date of this AD but not to exceed 1,500 hours total time in service on the part, replace the lower coupling drive shaft P/N 269A5504, with a shaft P/N 269A5504-3.
(Hughes Service Information Notices Nos. 2A-33(269A), 2A-1-01(269A-1) and 2B- 01(269B), all dated February 18, 1964, cover this same subject.)
This directive effective March 18, 1964.