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<DIV>Earl,</DIV>
<DIV> </DIV>
<DIV>Your absolutely right on the automotive engine mount thing. The
Acuras that we work on have that same type of mount you are talking about.
I have thought hard about trying to make a viscous fluid type mount for my model
airplane. But the size, weight and type of materials and
machining would make it difficult to make in my garage. In order to
produce a smooth running single cylinder engine a counterbalance would have to
be incorporated. Thus adding weight and size to our power
plants. </DIV>
<DIV> I am not sure why but my current new plane is super smooth and quite
and it is using the same engine,mount,and exhaust system that I had in my old
plane(different design). I am sure it has much to do with the shape
and size of the fuse and wings more then anything then the type of mount or
engine or its just the right combination of the whole package.</DIV>
<DIV> </DIV>
<DIV>Wayne Galligan</DIV>
<DIV> </DIV>
<DIV>--- Original Message ----- </DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=EHaury@aol.com href="mailto:EHaury@aol.com">EHaury@aol.com</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Thursday, February 19, 2004 10:21
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Tonight's Dumb Idea...</DIV>
<DIV><BR></DIV>
<DIV>Lance</DIV>
<DIV> </DIV>
<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>
<DIV> </DIV>
<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>
<DIV> </DIV>
<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>
<DIV> </DIV>
<DIV>Earl</DIV></BLOCKQUOTE></BODY></HTML>