Originally Posted by
DrScoles
I thought just the same thing the other day after reading some of these posts. I'll do a tight turn at 200mph with my bobcat and a P120, that has to load the bearings on the turbine 10X more than a flat spin. No? I'm not an engineer, but I do think I have a fair amount of common sense.
Mike, its not the centrifugal force (G loading) that's the issue. Its the gyroscopic effects of the axis of rotation changing quickly, causing loads on the bearing in addition to G's pulled.
A ~10G turn will give high centrifugal loads, but a shaft assembly weighing 10X the weight still isn't much. In that case, the change in rotational axis direction is actually quite slow as well. 3D manuvers and flopping around, etc. are low centrifugal but very high gyroscopic due to the rapid change in shaft orientation. I haven't done any of the math, but that's the underlying reason.
Kelly