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<DIV>Hi Bob:</DIV>
<DIV> </DIV>
<DIV>Hmm, you are right, the guide doesn't say anything explicitely about track
shift. I've been to their judging class and this got talked to
death. The outcome was that Ray Rose instructed us that there ought to be
some track displacement and that there was no particular downgrade for the
displacement itself. Different event, different rules I know, but the
physics are the same. A real snap is going to have some displacement, so
we ought to be expecting it and not downgrading when we see it happen. I
think it's hard to see the displacement in many cases and we ought to be much
more focused on the pitch break at the onset of autorotation and rotating motion
of the tail during the autorotation to tell that a snap really happened.</DIV>
<DIV> </DIV>
<DIV>Ed</DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=rcaerobob@cox.net href="mailto:rcaerobob@cox.net">Bob Pastorello</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> Wednesday, December 29, 2004 7:27
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Displacement during snap
rolls (was Why is it so quiet?)</DIV>
<DIV><BR></DIV>
<DIV>Ed - I checked the IMAC Flying and Judging Guide; couldn't find a
comment to address this question of lateral shift of track.</DIV>
<DIV> </DIV>
<DIV>Anywhere else to look?</DIV>
<DIV><BR>Bob Pastorello<BR>NSRCA 199 AMA 46373<BR><A
href="mailto:rcaerobob@cox.net">rcaerobob@cox.net</A><BR><A
href="http://www.rcaerobats.net">www.rcaerobats.net</A></DIV>
<DIV> </DIV>
<DIV> </DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=Rcmaster199@aol.com
href="mailto:Rcmaster199@aol.com">Rcmaster199@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> Tuesday, December 28, 2004 11:17
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Displacement during snap
rolls (was Why is it so quiet?)</DIV>
<DIV><BR></DIV><FONT id=role_document face=Arial color=#000000 size=2>
<DIV>
<DIV>I am interested in what this Scale Aerobatics Judging guide has to say.
Is there a web site?</DIV>
<DIV> </DIV>
<DIV>MattK</DIV>
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style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><FONT
style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size=2>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=mailto:Ed_Alt@hotmail.com href="mailto:Ed_Alt@hotmail.com">Ed
Alt</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=mailto:discussion@nsrca.org
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, December 28, 2004
11:04 PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Displacement during snap
rolls (was Why is it so quiet?)</DIV>
<DIV><BR></DIV>
<DIV><FONT face=Arial size=2>Good topic Bob. If the model really did
a snap roll, it had to displace somewhat. If not, and if you could
actually tell that it did not, that could be an indicator that a snap
roll did not actually happen. Generally, the model has to displace to a
new track, however slight, from the yawing and pitching moments
introduced. The criteria should perhaps be that you are able to able
to maintain the new track exactly in parallel to the pre-snap track.
How much offset is OK is hard to say, but things generally start looking
suspicious whan it's much more than a couple of wingspans. You would
generally start to see other obvious problems, such as barrel rolling, if
the displacement were really large. For another perspective, I think
the Scale Aerobatics Flying and Judging Guide does a decent job
of describing how to grade a snap.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Ed</FONT></DIV></FONT></BLOCKQUOTE></DIV>
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