<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><BR><DIV><DIV>On Jul 8, 2006, at 11:12 PM, Ed Alt wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"> <DIV><FONT face="Arial" size="2">To Doug's point re. the long tail moments & added stability of Pattern designs, this can be overcome pretty well with enough control throw. Granted, it's not going to be just like a Scale Aerobatic design, but real snaps can be done and barrel rolls can be avoided. I remember the angst that was generated by the reverse avalance in Masters in '05. Fears of bent wing tubes, busted wings etc. Locally at least, there were several examples where very good pilots had to re-do their setups to get enough throw to make this maneuver happen properly and not bend their airplanes. Well, not a single airplane in the district was damaged that I know about, but I do remember having discussions about upping the elevator and also rudder throws to get the autorotation to happen properly. Hey, I admit to having only a short 2.25 year Pattern flying history, but as far as I can tell, it doesn't seem to be part of the Pattern "DNA" to set airplanes up with enough throw in alot of cases. Having the deal with a schedule including the loaded snap in the reverse avalanche has advanced the knowledge because guys had to figure it out.</FONT></DIV></BLOCKQUOTE><DIV><BR class="khtml-block-placeholder"></DIV>Here's a good example of what Ed's talking about relative to using enough control throw to get a good snap: I have a Focus I (very long tail moment) and use 6 degrees of elevator throw for normal flying, but it requires 20 degrees of elevator throw to get a good snap. It sounds excessive, but, if I use less elevator, I have to cut way down on aileron throw to be able to stop it before it over rolls the snap and the snap doesn't look "right".</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Ron Van Putte</DIV><DIV><BLOCKQUOTE type="cite"> <BLOCKQUOTE 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="seefo@san.rr.com" href="mailto:seefo@san.rr.com">Doug Cronkhite</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A title="nsrca-discussion@lists.nsrca.org" href="mailto:nsrca-discussion@lists.nsrca.org">'NSRCA Mailing List'</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, July 08, 2006 8:54 PM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [NSRCA-discussion] Snaps</DIV> <DIV><BR></DIV> <DIV class="Section1"><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">The INBOARD wing dumps lift as a result of the increases angle of attack AND the rapid reduction of airspeed (by a sharp yaw moment – rudder input). The outboard wing’s lift and drag increase rapidly. If the outboard wing dumped lift you’d get no rotation at all or very little. Some airplanes actually snap much better with no aileron usage as the changes in angle of attack on the inboard wing causes it to keep flying and not dump the lift from the yaw input.<O:P></O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><O:P> </O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">I think the biggest problem pattern aircraft have with performing proper snaps is the long long tail moments keep things so stable that it’s very hard to generate the critical angle of attack required to get the stall to happen. So you see barrel rolls with VERY high G-loads on the aircraft. <O:P></O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><O:P> </O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">In full scale aerobatics, there is nearly no G-loading once the stall occurs, except for the rotational forces of the autorotation of the aircraft. There is some G leading up to the break, but once that happens, it’s all kind of non-stressful. <O:P></O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><O:P> </O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial">-Doug<O:P></O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"> <O:P></O:P></SPAN></FONT></P><P class="MsoNormal"><FONT face="Arial" color="navy" size="2"><SPAN style="FONT-SIZE: 10pt; COLOR: navy; FONT-FAMILY: Arial"><O:P> </O:P></SPAN></FONT></P> <DIV> <DIV class="MsoNormal" style="TEXT-ALIGN: center" align="center"><FONT face="Times New Roman" size="3"><SPAN style="FONT-SIZE: 12pt"> <HR tabindex="-1" align="center" width="100%" size="2"> </SPAN></FONT></DIV><P class="MsoNormal"><B><FONT face="Tahoma" size="2"><SPAN style="FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Tahoma">From:</SPAN></FONT></B><FONT face="Tahoma" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Tahoma"> nsrca-discussion-bounces@lists.nsrca.org [<A href="mailto:nsrca-discussion-bounces@lists.nsrca.org">mailto:nsrca-discussion-bounces@lists.nsrca.org</A>] <B><SPAN style="FONT-WEIGHT: bold">On Behalf Of </SPAN></B><A href="mailto:Rcmaster199@aol.com">Rcmaster199@aol.com</A><BR><B><SPAN style="FONT-WEIGHT: bold">Sent:</SPAN></B> Saturday, July 08, 2006 12:45 PM<BR><B><SPAN style="FONT-WEIGHT: bold">To:</SPAN></B> nsrca-discussion@lists.nsrca.org<BR><B><SPAN style="FONT-WEIGHT: bold">Subject:</SPAN></B> Re: [NSRCA-discussion] Snaps</SPAN></FONT><O:P></O:P></P></DIV><P class="MsoNormal"><FONT face="Times New Roman" size="3"><SPAN style="FONT-SIZE: 12pt"><O:P> </O:P></SPAN></FONT></P> <DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">In a message dated 7/8/2006 2:09:25 PM Eastern Standard Time, <A href="mailto:natpenton@centurytel.net">natpenton@centurytel.net</A> writes:<O:P></O:P></SPAN></FONT></P></DIV> <BLOCKQUOTE style="BORDER-RIGHT: medium none; PADDING-RIGHT: 0in; BORDER-TOP: medium none; MARGIN-TOP: 5pt; PADDING-LEFT: 4pt; MARGIN-BOTTOM: 5pt; PADDING-BOTTOM: 0in; MARGIN-LEFT: 3.75pt; BORDER-LEFT: blue 1.5pt solid; PADDING-TOP: 0in; BORDER-BOTTOM: medium none"> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Matt<O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Regards. Two comments. <O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Snap characteristics are independent of scale. The only thing that changes is the clock ( due to changes in moments of inertia ). <O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">When the rudder is applied it is the outboard wing that exceeds the stall AOA and dumps. Actually it is not much of a lift dump but a huge jump in drag.<O:P></O:P></SPAN></FONT></P></DIV></BLOCKQUOTE></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">Nat true. Moments of inertia are design parameters. So are several other key parameters that may make or break a model's ability to perform snaps. That was my point.<O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> <O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">I agree in terms of AOA (outboard aileron low) and drag increase but I am not as sure regards to lift. I know what you are saying though. <O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> <O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial">One question: how does the outboard panel lift over the top if its lift has been dumped?<O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> <O:P></O:P></SPAN></FONT></P></DIV> <DIV><P class="MsoNormal"><FONT face="Arial" size="2"><SPAN style="FONT-SIZE: 10pt; FONT-FAMILY: Arial"> <O:P></O:P></SPAN></FONT></P></DIV></DIV><DIV> <BR class="khtml-block-placeholder"></DIV><HR><DIV><BR class="khtml-block-placeholder"></DIV>_______________________________________________<BR>NSRCA-discussion mailing list<BR><A href="mailto:NSRCA-discussion@lists.nsrca.org">NSRCA-discussion@lists.nsrca.org</A><BR>http://lists.nsrca.org/mailman/listinfo/nsrca-discussion</BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">_______________________________________________</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">NSRCA-discussion mailing list</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="mailto:NSRCA-discussion@lists.nsrca.org">NSRCA-discussion@lists.nsrca.org</A></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><A href="http://lists.nsrca.org/mailman/listinfo/nsrca-discussion">http://lists.nsrca.org/mailman/listinfo/nsrca-discussion</A></DIV> </BLOCKQUOTE></DIV><BR></BODY></HTML>