<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML><HEAD>
<META http-equiv=Content-Type content="text/html; charset=iso-8859-1">
<META content="MSHTML 6.00.2900.2668" name=GENERATOR>
<STYLE></STYLE>
</HEAD>
<BODY dir=ltr bgColor=#ffffff>
<DIV><FONT face=Arial size=2>Hello Bill</FONT></DIV>
<DIV><FONT face=Arial size=2>Just finished series of tests with OS140RX
20% nitro 17% oil.</FONT></DIV>
<DIV><FONT face=Arial size=2>OS header and ES 20" CF tune pipe and Hyde ARIA
mount. Test is 3 meters from the model on grass field:</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>APC 17x12 2
blades = ~ 91.5 - 93dB (Very powerful but risky for competition and
slow down rate is low)</FONT></DIV>
<DIV><FONT face=Arial size=2>
<DIV><FONT face=Arial size=2>APC 16x14 2
blades = ~ 89 - 90dB (Powerful but fly too fast
slow down rate is low)</FONT></DIV>
<DIV>
<DIV><FONT face=Arial size=2>APC 16x12 2
blades = Not tested yet</FONT></DIV>
<DIV></FONT><FONT face=Arial size=2><FONT face=Arial size=2>APC 15.75x13 3
blades = ~ 88 - 90dB (Good performance, slow down
rate is better but not enough)</FONT></DIV></DIV></DIV></FONT>
<DIV><FONT face=Arial size=2>
<DIV><FONT face=Arial size=2>APC 15.5x12 4 blades = ~ 86 -
98dB (Best flying on normal conditions. Will have
not enough power on strong windy day, very good speed
control)</FONT></DIV>
<DIV> </DIV>
<DIV>Not tested but I am tending to think that for YS160 the 4 blades will
be a good solution.</DIV>
<DIV></FONT><FONT face=Arial size=2></FONT> </DIV></DIV>
<DIV><FONT face=Arial size=2>Amram</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2></FONT> </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=Aviram@ashrad.com href="mailto:Aviram@ashrad.com">Aviram Arbel</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> Monday, June 27, 2005 9:35 AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> RE: Noise Limits for FAI</DIV>
<DIV><FONT face=Arial size=2></FONT><FONT face=Arial size=2></FONT><BR></DIV>
<DIV dir=ltr align=left><SPAN class=874393507-27062005><FONT face=Arial
color=#0000ff size=2>Hi Bill</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=874393507-27062005><FONT face=Arial
color=#0000ff size=2>I'm using APC 4 blade 15.5X12 30% CP - 87-89 DB
</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=874393507-27062005><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=874393507-27062005><FONT face=Arial
color=#0000ff size=2>Aviram</FONT></SPAN></DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=rtl align=right>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> <A
href="mailto:discussion-request@nsrca.org">discussion-request@nsrca.org</A>
[mailto:discussion-request@nsrca.org] <B>On Behalf Of </B><A
href="mailto:vicenterc@comcast.net">vicenterc@comcast.net</A><BR><B>Sent:</B>
Monday, June 27, 2005 3:50 AM<BR><B>To:</B> <A
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A>; <A
href="mailto:discussion@nsrca.org">discussion@nsrca.org</A><BR><B>Cc:</B>
William Ahrens<BR><B>Subject:</B> Re: Noise Limits for
FAI<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV>Hi Bill,</DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>Did you check wiht 3 or 4 blade prop? Probably you could reduce it
wiht those props.</DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>Vicente</DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<BLOCKQUOTE
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px solid">--------------
Original message -------------- <BR><BR>> Group <BR>> <BR>> For a
YS 160 what prop and exhaust will get me to 94dB(A) and work well. <BR>>
<BR>> Currently using a 17 x 12 wide with EX Composite pipe and 30
percent Nitro. <BR>> Today at about 101 degrees heat index my plane
measured about 98dB(A) with a <BR>> Radio Shack meter. <BR>> <BR>>
Thanks <BR>> Bill <BR>> <BR>>
================================================= <BR>> To access the
email archives for this list, go to <BR>>
http://lists.f3a.us/pipermail/nsrca-discussion/ <BR>> To be removed from
this list, go to http://www.nsrca.org/discussionA.htm <BR>> and follow
the instructions. <BR>> <BR>> List members email returned for mailbox
full will be removed from the list. <BR>>
</BLOCKQUOTE></BLOCKQUOTE></BODY></HTML>