Now that you guys have hopefully finished with the condescending remarks, perhaps we could continue the conversation. Some replies did give a good reminding information about vibration and I now have an incident report that I plan to read. Thanks to those posters.
I expect that tdracer has some more good information that he could post on the subject which is what normally happens. Obviously, making useless comments on a thread by people who don't know what they are talking about is frustrating(as we frequently) but a technical question that is obvously showing that the person is a neophyte can lead to some interesting info, if we don't intimidate them off the board.