Seems like " discussions" always center on torsional vibration testing, or the lack of it when alternative engines are the subject of the discussion. The topic of PSRUs then becomes the dominant point of discussion, and there is always lively discourse about the need for a PSRU and the resultant possibility of problems. It occurred to me that seldom ( if ever) doesthe subject of DIRECT DRIVE failure ever get a thorough discussion. I believe that in general, PSRUs have their "sweet spot" as a choice for engine conversions. Smaller engines seem to thrive on them but there are smaller direct drives that work well too. When you move up to the BIG BOY engines, it seems more difficult to make them work. Getting on with my point for this thread, I would like to hear about examples of DIRECT DRIVE conversions that have had engine or drive failures. I don't know about a lot of them, so here is a chance to bring it to the fore. While all types of examples are welcome, I would especially like to hear about any failures due to TV.