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<DIV>Lance</DIV>
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<DIV>The auto folks spend a lot of time trying to isolate (rather smooth) engines so that our vehicles are pleasant to operate. The fewer the cylinders, the larger the task. A few years ago I was intrigued by a mount design that consisted of an elastomeric material with enclosed chambers of different sizes that were fluid filled and connected by passages that were sized so that the fluid failed to flow (transfer) at certain frequencies. This allowed them to tune the mount for a range of conditions. Somewhat similar to shock absorber technology and possibly applicable toward providing variable dampening to the YS type mount.</DIV>
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<DIV>I've wondered if the stretching of the elastomer at high throttle changes the characteristic of the Hyde type mount beneficially. Allowing for some frequency dampening variability over the operating range.</DIV>
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<DIV>Certainly resonance issues with mechanical systems are often very complex. Amazing how well we've gotten our airplanes to work by trial and error.</DIV>
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<DIV>Earl</DIV></BODY></HTML>