69-15-02 BELL: Amdt. 39-815. Applies to Model 206A helicopters equipped with magnesium cyclic bellcrank support assemblies.
Compliance required as indicated.
To prevent failure of the magnesium cyclic bellcrank support assemblies, P/N 206-001- 521, due to fatigue cracks, accomplish the following:
(a) Inspect the right- and left-hand support assemblies, P/N 206-001-521, that have accumulated 25 hours' total time in service after April 15, 1969, before the first flight of each day as follows:
(1) Remove the upper forward cowling, P/N 206-061-801, to expose the hydraulic power cylinders.
(2) Inspect the attachment of the support assemblies to the fuselage for firmness by grasping with the fingers. If the support assembly is loose, torque the nut on the NAS 1304-9 bolt to 80 to 100 inch-pounds and the nut on the NAS 1305-9 bolt to 120 to 145 inch-pounds. If a nut is inaccessible, torque the bolt head in accordance with the method described in paragraph 4 ofBell Helicopter Company Service Bulletin No. 206A-11 Revision A, dated July 23, 1969, or in accordance with a method approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, Southwest Region, FAA.
(3) Inspect visually the right and left-hand support assemblies, P/N 206-001- 521, for cracks in the spotfaced areas around the attachment bolts and in the fillet radii between the base and vertical section of the supports, using a flashlight or equivalent. Both the forward and aft flange fillet radii and spotfaced areas must be inspected.
(4) Smooth out any nicks or corrosion visible in the forward and aft flange fillet radii and the spotfaced areas, using a fine file and crocus cloth.
(b) Remove and replace the support assembly before further flight if cracks are found. Inspect cyclic control rigging in accordance with paragraph 4-30 of the Model 206A Maintenance and Overhaul Instructions when the support assembly is replaced.
(c) Remove and replace right- and left-hand magnesium support assemblies with new aluminum support assemblies, P/N 206-001-544, within 100 hours' time in service after the effective date of this AD in accordance with the procedures in Bell Helicopter Company Service Bulletin No. 206A-11 Revision A, dated July 23, 1969, or in accordance with a procedure approved by the Chief, Engineering and Manufacturing Branch, Flight Standards Division, Southwest Region, FAA.
(d) The inspections in paragraph (a) are no longer required when aluminum bellcrank supports are installed in accordance with paragraph (c).
(Bell Model 206A Maintenance and Overhaul Manual Interim Revision No. 206A-69-16 pertains partially to this subject.)
This supersedes Amendment 39-746 (34 F.R. 6472), AD 69-07-03.
This amendment becomes effective August 16, 1969.