X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imo-d23.mx.aol.com ([205.188.139.137] verified) by logan.com (CommuniGate Pro SMTP 5.2.11) with ESMTP id 3411585 for flyrotary@lancaironline.net; Mon, 05 Jan 2009 12:48:23 -0500 Received: from WRJJRS@aol.com by imo-d23.mx.aol.com (mail_out_v39.1.) id q.cfb.4b29e26c (37133) for ; Mon, 5 Jan 2009 12:48:16 -0500 (EST) Received: from smtprly-da02.mx.aol.com (smtprly-da02.mx.aol.com [205.188.249.145]) by cia-ma02.mx.aol.com (v121_r5.5) with ESMTP id MAILCIAMA027-5bb7496247db258; Mon, 05 Jan 2009 12:48:17 -0500 Received: from WEBMAIL-DF11 (webmail-df11.webmail.aol.com [205.188.104.75]) by smtprly-da02.mx.aol.com (v121_r5.5) with ESMTP id MAILSMTPRLYDA026-5bb7496247db258; Mon, 05 Jan 2009 12:48:11 -0500 References: To: flyrotary@lancaironline.net Subject: Re: [FlyRotary] Re: 20B install issues overcome Date: Mon, 05 Jan 2009 12:48:11 -0500 X-AOL-IP: 66.253.96.220 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: wrjjrs@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CB3D74E9101096_14CC_38_WEBMAIL-DF11.sysops.aol.com" X-Mailer: AOL Webmail 40627-STANDARD Received: from 66.253.96.220 by WEBMAIL-DF11.sysops.aol.com (205.188.104.75) with HTTP (WebMailUI); Mon, 05 Jan 2009 12:48:11 -0500 Message-Id: <8CB3D74E8EC4D32-14CC-20@WEBMAIL-DF11.sysops.aol.com> X-Spam-Flag:NO ----------MB_8CB3D74E9101096_14CC_38_WEBMAIL-DF11.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Mark, Take a look at the newest Mistral pictures. They are using a tangental with=20= a "cool tube" something that I drew several years ago for PL's site. They us= e a large down pipe with a annular exit around the tube. If you are doing so= mething 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 per= ception of quietness.=C2=A0 As for the muffler/resonator, 6db is a significa= nt reduction.=C2=A0 I think I still have the drawings you provided.=C2=A0 Th= e nice thing about the tangential muffler design is that it will fit inside=20= my cowl.=C2=A0 The muffler/resonator should fit where the Hushpower 2 is now= .=C2=A0 We'll see. Mark On Sun, Jan 4, 2009 at 10:17 AM, Al Gietzen wrote: Subject: [FlyRotary] Re: 20B install issues overcome =C2=A0 My exhaust exits about 6-7 inches from prop and goes through near the root o= f the blades (pusher). It occurs to me that having my exhaust exit through t= he prop may help reduce or mask the exhaust noise. =C2=A0On 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 th= e 20B =E2=80=93 could make a difference. =C2=A0 The secondary muffler/resonat or I have also helps. =C2=A0On the dyno we measured that resulted in about 6= db reduction. =C2=A0 Al G Agree.=C2=A0 Unfortunately, that's not a comment I hear.=C2=A0 On the contra= ry, they usually tell me that they can hear me before they can see me.=C2= =A0 ;-(=C2=A0=20 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 made fro= m inconel, similar to your design.=C2=A0 I take it from your report that you= r muffler is holding up well?=C2=A0 =C2=A0 =C2=A0 =C2=A0=C2=A0=20 Mark S. =C2=A0 So far it is doing fine. =C2=A0And the inconel tangential and the 321SS seco= ndary muffler (my own design) quiet it down nicely.=C2=A0 A few days ago I p= icked up my brother to go for a ride, while my sister-in-law waited and watc= hed other planes come and go.=C2=A0 When we got back her remark was that my=20= plane was quieter than all the rest. =C2=A0I consider that to be 'expert tes= timony'J. Al G On Sat, Jan 3, 2009 at 5:47 PM, Al Gietzen wrote: Al,=20 That's a great shot.=C2=A0 Have you had any "significant issues" with your i= nstall?=C2=A0 If so, how did you overcome them? Mark S.=C2=A0=20 I had 2 issues that required some time and determination. The first was the=20= RWS EC2.=C2=A0 I had an early version for the 3-rotor, and perhaps the first= installed in a composite airplane. =C2=A0I had some kind of electrical nois= e related corruption of settings which p ersisted through a lot of effort for over a years time. It has been resolved= , and the engine running fine.=C2=A0 That has been discussed here more than=20= 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. =C2=A0The=20= theory was that the differential pressure below/above the wing would help pr= ovide the necessary air flow.=C2=A0 Not the case here as the location is too= far back on the wing; and behind the strake (the inboard section on the can= ard airplane). =C2=A0The pressure differential turned out to be only about 1= " H20 =E2=80=93 very little help.=C2=A0 I added a ram scoop, and installed a= small oil/water heat exchanger in the cowl.=C2=A0 Currently oil temps are f= ine, and the coolant temp is running a bit lower than I like at cruise.=C2= =A0 I may eventually install some sort of air flow adjustment, or even consi= der installing a thermostat in the engine. =C2=A0You may recall discussion o= f these changes here in the past as well. I'm just past 140 hours flying time, and feel quite fortunate with how well=20= things have worked out.=C2=A0 Performance and economy are great. Al G=C2=A0=C2=A0 http://members.cox.net/alg3/airplane.htm =C2=A0 =C2=A0 =C2=A0 =C2=A0 ----------MB_8CB3D74E9101096_14CC_38_WEBMAIL-DF11.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="utf-8" Mark,
Take a look at the newest Mistral pictures. They are using a tangental with=20= a "cool tube" something that I drew several years ago for PL's site. They us= e a large down pipe with a annular exit around the tube. If you are doing so= mething 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 issues overcome

I guess the prop= chopping the noise stream could account for some of the perception of quiet= ness.  As for the muffler/resonator, 6db is a significant reduction.&nb= sp; I think I still have the drawings you provided.  The nice thing abo= ut the tangential muffler design is that it will fit inside my cowl.  T= he muffler/resonator should fit where the Hushpower 2 is now.  We'll se= e.

Mark

On Sun, Jan 4, 2009 at 10:17 AM, Al Gietzen <ALVentures@cox.net>= ; wrote:
Subject: [FlyRotary] Re: 20B install issues overcome
 
My exhaust exits about 6-7 inches fro= m prop and goes through near the root of the blades (pusher). It occurs to m= e that having my exhaust exit through the prop may help reduce or mask the e= xhaust noise.  On a takeoff roll there is a prop blade breaking that ex= haust stream about 130 times per second. Let's see, that's about 1 blade pas= sing for every two exhaust pulses on the 20B =E2=80=93 could make a differen= ce.
 
The secondary muffler/resonator I hav= e also helps.  On the dyno we measured that resulted in about 6 db redu= ction.
 
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 <ALVentures@cox.net= > wrote:
I'm pres= ently gathering materials to fabricate a tangential muffler made from incone= l, similar to your design.  I take it from your report that your muffle= r is holding up well?        

Mark S.
 
So far it is doing fine.  And the incon= el tangential and the 321SS secondary muffler (my own design) quiet it down=20= nicely.  A few days ago I picked up my brother to go for a ride, while=20= my sister-in-law waited and watched other planes come and go.  When we=20= got back her remark was tha t my plane was quieter than all the rest.  I consider that to be 'exper= t testimony'J.
Al G
On Sat, Jan 3, 2009 at 5:47 PM, Al= Gietzen <ALVentures@cox.net>= ; wrote:
Al,
That's a great shot.  Have you had any "significant issues" with your i= nstall?  If so, how did you overcome them?
Mark S. 
I had 2 issues that required some time and det= ermination. The first was the RWS EC2.  I had an early version for the=20= 3-rotor, and perhaps the first installed in a composite airplane.  I ha= d some kind of electrical noise related corruption of settings which persist= ed through a lot of effort for over a years time. It has been resolved, and th= e engine running fine.  That has been discussed here more than once in=20= the past.
The other was less-than-expected performance o= f an oil cooler built into the wing root, without much of a scoop for the in= let below the wing.  The theory was that the differential pressure belo= w/above the wing would help provide the necessary air flow.  Not the ca= se here as the location is too 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 =E2=80=93 very little help.  I adde= d a ram scoop, and installed a small oil/water heat exchanger in the cowl.&n= bsp; Currently oil temps are fine, and the coolant temp is running a bit low= er than I like at cruise.  I may eventually install some sort of air fl= ow adjustment, or even consider installing a thermostat in the engine.  = ;You may recall discussion of these changes here in the past as well.=
I'm just past 140 hours flying time, and feel=20= quite fortunate with how well things have worked out.  Performance and=20= economy are great.
 
 
 
 


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