Originally Posted by
ShyTorque
I can imagine a scenario where the damaged section of the driveshaft cover was pressed downwards onto the shaft, a score line could easily be formed, such that the shaft broke cleanly across it. These driveshafts are lightweight by design and it wouldn't take much damage to cause it to shear.
I consider myself lucky to have escaped an inclined driveshaft failure on an S-76 when an inadequately secured part of the wiring harness contacted it (a maintenance error). As it happened, it involved the wiring to the TGB chip detector and that shorted out, putting on the chip warning light. I put out a Pan call and inside two minutes I was on the ground at the minor airfield I just happened to passing and talking to. Even by then, although the wiring wasn't heavy in weight, it had badly scored the shaft, which had to be scrapped.
Similar on a 330. One of the clips securing the GPS antenna wire had failed and the wire sagged just enough to touch the top of the TRDS. No idea how long it had been like that but it had already removed the paint off the shaft.