FROM BHT
The Bell position on the approved gimbal ring is quite clear and very simple. ASB 47-76-4 was issued on 5 April 1976 and requires the installation of gimbal ring assembly 47-120-014-23 not later than 1 September 1976 regardless of the number of flight hours on the previous gimbal ring assembly. Gimbal ring assembly 47-120-014-23 has a 4800 hour retirement life and is usable on all commercial Bell 47 model designations. No other Bell 47 gimbal ring assembly is authorized for use by Bell Helicopter.