NEW TN DG-500 and DG-800 – LIFE TIME OF DRIVE BELT
The life-time of the drive belt was limited initially to 50 h engine time. This limitation had no rational substantiation. It was just set to a reasonable limit to gain experience.
Now after about 3 decades of operational experience DG found that the max. life-time limitation of the drive belts is not necessary, as only failures (belt torn off) have been reported during engine start on the ground, but never in the air. Therefor the drive belts may be operated on condition. A thorough periodical check of the belts after 50 belt operation hours and then every following 25 operation hoursd is mandatory.
You find the new TNs here.