61-22-01 BELL: Amdt. 361 Part 507 Federal Register November 7, 1961. Applies to All Model 47 Series Helicopters.
Compliance required as indicated.
To preclude failure of the main rotor pitch link rod end bearing P/N RE4F7 which causes loss of main rotor control, the following one-time only inspection is required to determine that the bearing is correctly installed.
(a) Within the next 10 hours' time in service after the effective date of this AD, on all Model 47 Series helicopters, inspect the main rotor control pitch link located between the stabilizer bar mixing lever and the main rotor blade control horn to see that the rod end bearing sides are parallel to the clevis slot. These surfaces must be adjusted parallel to prevent binding of the rod end bearing at extreme ends of travel, as specified in all applicable model maintenance manuals.
(b) Within the next 10 hours' time in service after the effective date of this AD, inspect all Models 47D, 47D-1, 47H-1, 47G, 47G-2, and 47J helicopters equipped with Fafnir P/N RE4F7 rod end bearing as follows:
(1) Remove the RE4F7 rod end bearing in accordance with the applicable maintenance manual and visually inspect for obvious damage or defect of the outer race such as nicks and gouges adjacent to the shield, looseness, roughness, distortion or kinks in bearing shields.
(2) If any damage or defect is found, replace the bearing prior to further flight.
(3) If no damage or defect is found, the bearing may be reinstalled.
(4) The installation of the bearings under subparagraphs (2) or (3) shall be made in accordance with the applicable maintenance manual making positive that requirements of paragraph (a) are followed.
(c) Helicopters listed in paragraph (b) that are not equipped with the Fafnir P/N RE4F7 bearings are equipped with Bell P/N 47-140-241-3 rod end bearings. These bearings are of a different make and only require the inspection called for in paragraph (a).(Bell Service Instruction 345 SI covers this same subject for the models listed under (b)).
This directive effective November 7, 1961.