X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from rv-out-0506.google.com ([209.85.198.236] verified) by logan.com (CommuniGate Pro SMTP 5.2.11) with ESMTP id 3411708 for flyrotary@lancaironline.net; Mon, 05 Jan 2009 14:05:20 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.198.236; envelope-from=msteitle@gmail.com Received: by rv-out-0506.google.com with SMTP id f6so9323360rvb.7 for ; Mon, 05 Jan 2009 11:04:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:in-reply-to:mime-version:content-type:references; bh=9taNkOyP9QGsXwDlC4aRvHPGfpOhwK5cK2DV+x08kTk=; b=NdQhNbWJXmUeet2tRmQtj/EDoQ8aicVTUzTANOqsGSc4HU02Rr3bWpBTrdE0Q9qwLe aigH+X4Dg+b+iq2E4gYlLwuhZCkjmB8DltQQ+w1i/CArEHr8Eh8MNmwBVbX7/uFlQHZK 6Y9xIw3iDwcEFflXw2ljzOyLylTrOWvuiVxt4= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:in-reply-to:mime-version :content-type:references; b=GStLRyEIDnwJBXdwQw71VguZqaeKa1AEVQMTMzjmthVtCZOOWWpEXn0kichC+Lt4Kl 2zTcqy/rJ9fwpDAqCk7hOeez9Iz2cUi4hiipEBJxMhUyVw9lxEXzdEhEZwxVP72lr+Kf O/xEOpu/X5ByogZfIVRZgEDGIC75SHXaW+MME= Received: by 10.140.202.21 with SMTP id z21mr10527353rvf.68.1231182282744; Mon, 05 Jan 2009 11:04:42 -0800 (PST) Received: by 10.140.166.4 with HTTP; Mon, 5 Jan 2009 11:04:42 -0800 (PST) Message-ID: <5cf132c0901051104j3722d0f1lee2fb66a77f9f15e@mail.gmail.com> Date: Mon, 5 Jan 2009 13:04:42 -0600 From: "Mark Steitle" To: "Rotary motors in aircraft" Subject: Re: [FlyRotary] Re: 20B install issues overcome In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_113415_30274806.1231182282732" References: ------=_Part_113415_30274806.1231182282732 Content-Type: text/plain; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Bill, Yes, I remember the discussions surrouding the cool tube. I may give it a try, if for no other reason but to help the muffler live a little longer. Lowering the EGT surely couldn't hurt anything. Do you know of anyone who has actually tried the cool tube idea? Mark On Mon, Jan 5, 2009 at 11:48 AM, wrote: > Mark, > Take a look at the newest Mistral pictures. They are using a tangental wi= th > a "cool tube" something that I drew several years ago for PL's site. They > use a large down pipe with a annular exit around the tube. If you are doi= ng > something new it is worth a look. Material is 321 I think. > Bill Jepson > > > -----Original Message----- > From: Mark Steitle > To: Rotary motors in aircraft > Sent: Sun, 4 Jan 2009 8:45 am > Subject: [FlyRotary] Re: 20B install issues overcome > > I guess the prop chopping the noise stream could account for some of the > perception of quietness. As for the muffler/resonator, 6db is a signific= ant > reduction. I think I still have the drawings you provided. The nice thi= ng > about the tangential muffler design is that it will fit inside my cowl. = The > muffler/resonator should fit where the Hushpower 2 is now. We'll see. > > Mark > > On Sun, Jan 4, 2009 at 10:17 AM, Al Gietzen wrote: > >> *Subject:* [FlyRotary] Re: 20B install issues overcome >> >> My exhaust exits about 6-7 inches from prop and goes through near the ro= ot >> of the blades (pusher). It occurs to me that having my exhaust exit thro= ugh >> the prop may help reduce or mask the exhaust noise. On a takeoff roll t= here >> is a prop blade breaking that exhaust stream about 130 times per second. >> Let's see, that's about 1 blade passing for every two exhaust pulses on = the >> 20B =96 could make a difference. >> >> The secondary muffler/resonator I have also helps. On the dyno we >> measured that resulted in about 6 db reduction. >> >> Al G >> Agr ee. Unfortunately, that's not a comment I hear. On the contrary, >> they usually tell me that they can hear me before they can see me. ;-( >> >> Mark S. >> ANR headsets mandatory >> On Sun, Jan 4, 2009 at 12:22 AM, Al Gietzen wrote: >> I'm presently gathering materials to fabricate a tangential muffler mad= e >> from inconel, similar to your design. I take it from your report that y= our >> muffler is holding up well? >> >> Mark S. >> >> So far it is doing fine. And the inconel tangential and the 321SS >> secondary muffler (my own design) quiet it down nicely. A few days ago = I >> picked up my brother to go for a ride, while my sister-in-law waited and >> watched other planes come and go. When we got back her remark was tha t= my >> plane was quieter than all the rest. I consider that to be 'expert >> testimony'J. >> Al G >> On Sat, Jan 3, 2009 at 5:47 PM, Al Gietzen wrote: >> Al, >> >> That's a great shot. Have you had any "significant issues" with your >> install? If so, how did you overcome them? >> Mark S. >> I had 2 issues that required some time and determination. The first was >> the RWS EC2. I had an early version for the 3-rotor, and perhaps the fi= rst >> installed in a composite airplane. I had some kind of electrical noise >> related corruption of settings which persisted through a lot of effort f= or >> over a years time. It has been resolved, and the engine running fine. T= hat >> has been discussed here more than once in the past. >> The other was less-than-expected performance of an oil cooler built into >> the wing root, without much of a scoop for the inlet below the wing. Th= e >> theory was that the differential pressure below/above the wing would hel= p >> provide the necessary air flow. Not the case here as the location is to= o >> far back on the wing; and behind the strake (the inboard section on the >> canard airplane). The pressure differential turned out to be only about= 1" >> H20 =96 very little help. I added a ram scoop, and installed a small >> oil/water heat exchanger in the cowl. Currently oil temps are fine, and= the >> coolant temp is running a bit lower than I like at cruise. I may eventu= ally >> install some sort of air flow adjustment, or even consider installing a >> thermostat in the engine. You may recall discussion of these changes he= re >> in the past as well. >> I'm just past 140 hours flying time, and feel quite fortunate with how >> well things have worked out. Performance and economy are great. >> Al G http://members.cox.net/alg3/airplane.htm >> >> >> >> >> > > > ------------------------------ > Get a *free MP3* every day with the Spinner.com Toolbar. Get it Now. > > ------=_Part_113415_30274806.1231182282732 Content-Type: text/html; charset=WINDOWS-1252 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
Bill,
 
Yes, I remember the discussions surrouding the cool tube.  I may = give it a try, if for no other reason but to help the muffler live a little= longer.  Lowering the EGT surely couldn't hurt anything.  Do= you know of anyone who has actually tried the cool tube idea? 
 
Mark

On Mon, Jan 5, 2009 at 11:48 AM, <wrjjrs@aol.com> wrot= e:
Mark,
Take a look at the newe= st Mistral pictures. They are using a tangental with a "cool tube"= ; something that I drew several years ago for PL's site. They use a lar= ge down pipe with a annular exit around the tube. If you are doing somethin= g new it is worth a look. Material is 321 I think.
Bill Jepson


-----Original Message-----
From: Mark Steitle <= ;msteitle@gmail.com= >
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Sun, 4 Jan 2009 8:45 am
Subject: [FlyRotary] Re: 20B install issue= s overcome

I guess the prop chopping the noise stream could account for some of t= he perception of quietness.  As for the muffler/resonator, 6db is a si= gnificant reduction.  I think I still have the drawings you provided.&= nbsp; The nice thing about the tangential muffler design is that it will fi= t inside my cowl.  The muffler/resonator should fit where the Hushpowe= r 2 is now.  We'll see.

Mark

On Sun, Jan 4, 2009 at 10:17 AM, Al Gietzen <A= LVentures@cox.net> wrote:
Subject:= [FlyRotary] Re: 20B ins= tall issues overcome
 
My exhaust exits about 6-7 in= ches from prop and goes through near the root of the blades (pusher). It oc= curs to me that having my exhaust exit through the prop may help reduce or = mask the exhaust noise.  On a takeoff roll there is a prop blade break= ing that exhaust stream about 130 times per second. Let's see, that'= ;s about 1 blade passing for every two exhaust pulses on the 20B =96 could = make a difference.
 
The secondary muffler/resonat= or I have also helps.  On the dyno we measured that resulted in about = 6 db reduction.
 
Al G
<= font face=3D"Times New Roman" size=3D"3">Ag= r ee.  Unfortunately, that's not a comment I hear.  On the co= ntrary, they usually tell me that they can hear me before they can see me.&= nbsp; ;-( 

Mark S.
ANR headsets mandatory
On Sun, Jan 4, 2009 at 12:22= AM, Al Gietzen <ALVentures@cox.net> wrote:
I= 9;m presently gathering materials to fabricate a tangential muffler made fr= om inconel, similar to your design.  I take it from your report that y= our muffler is holding up well?        

Mark S.
<= font face=3D"Verdana" color=3D"blue" size=3D"2"> 
<= font face=3D"Verdana" color=3D"blue" size=3D"2">So far it is doing fine.  And = the inconel tangential and the 321SS secondary muffler (my own design) quie= t it down nicely.  A few days ago I picked up my brother to go for a r= ide, while my sister-in-law waited and watched other planes come and go.&nb= sp; When we got back her remark was tha t my plane was quieter than all the= rest.  I consider that to be 'expert testimony'= J.
<= font face=3D"Verdana" color=3D"blue" size=3D"2">Al G
<= span style=3D"FONT-SIZE: 12pt">On Sat, Jan 3, 2009 at 5:47 PM= , Al Gietzen <AL= Ventures@cox.net> wrote:
<= font face=3D"Times New Roman" size=3D"3">Al= ,

That's a great shot.  Have you had any "significant= issues" with your install?  If so, how did you overcome them? Mark S. 
I had 2 issues that required some tim= e and determination. The first was the RWS EC2.  I had an early versio= n for the 3-rotor, and perhaps the first installed in a composite airplane.=  I had some kind of electrical noise related corruption of settings w= hich persisted through a lot of effort for over a years time. It has been r= esolved, and the engine running fine.  That has been discussed here mo= re than once in the past.
The other was less-than-expected perf= ormance of an oil cooler built into the wing root, without much of a scoop = for the inlet below the wing.  The theory was that the differential pr= essure below/above the wing would help provide the necessary air flow. = ; Not the case here as the location is too far back on the wing; and behind= the strake (the inboard section on the canard airplane).  The pressur= e differential turned out to be only about 1" H20 =96 very little help= .  I added a ram scoop, and installed a small oil/water heat exchanger= in the cowl.  Currently oil temps are fine, and the coolant temp is r= unning a bit lower than I like at cruise.  I may eventually install so= me sort of air flow adjustment, or even consider installing a thermostat in= the engine.  You may recall discussion of these changes here in the p= ast as well.
I'm just past 140 hours flying ti= me, and feel quite fortunate with how well things have worked out.  Pe= rformance and economy are great.
 
 
<= span style=3D"FONT-SIZE: 12pt"> 
 


Get a free MP3 every day with the Spinner.com Toolbar. Get it Now.

------=_Part_113415_30274806.1231182282732--