langwadt wrote: I would have thought there was some kind of mechanical "fuse" if prop strikes are something that happens with any regularity.........The guys I know that spend half a car on a racing bicycle still use aluminium rims, with CF most damage requires replacement since it tends to fail catastrophically
There is no "mechanical fuse" for aircraft propellor strikes. They simply bend, break or dent. The degree to which they do depends upon the density of the debris or surface that they impact.
Of course, your comments about the relative impact response of a metal structure versus a composite structure is quite valid. Metal structures tend to fail more gracefully than composite structures due to impacts. This is one reason that most high-speed aircraft still use metal leading edges on their wings.