X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail04.syd.optusnet.com.au ([211.29.132.185] verified) by logan.com (CommuniGate Pro SMTP 5.2.11) with ESMTPS id 3413585 for flyrotary@lancaironline.net; Tue, 06 Jan 2009 15:50:45 -0500 Received-SPF: pass receiver=logan.com; client-ip=211.29.132.185; envelope-from=lendich@optusnet.com.au Received: from george (d58-109-48-212.dsl.nsw.optusnet.com.au [58.109.48.212]) by mail04.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id n06Knvnu025022 for ; Wed, 7 Jan 2009 07:49:59 +1100 Message-ID: <12238FD47DDD4D70A9EF882262ADC956@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: 20B install issues overcome Date: Wed, 7 Jan 2009 06:50:02 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0018_01C97094.2A2665C0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Antivirus: avast! (VPS 090106-1, 06/01/2009), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0018_01C97094.2A2665C0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Mike, Mufflers were never designed to fit into engine bays because of the size = and heat, that's why I have decided to have mine outside the cowl. The = fact that it is designed for cooling air both internally and externally, = and is designed aerodynamically for that, I believe that's the best = place for it. It may be that I can incorporate it into a cowl design so = that it's not too draggy - will just have to wait and see. BTW Bill Jepson had a big input into this design, but I have been a long = time in proving the design. George (down under) ----- Original Message -----=20 From: Mike Wills=20 To: Rotary motors in aircraft=20 Sent: Tuesday, January 06, 2009 12:54 PM Subject: [FlyRotary] Re: 20B install issues overcome I thought about it, but that hardware doesnt fit well in the RV-4 cowl = either. Mike ----- Original Message -----=20 From: Mark Steitle=20 To: Rotary motors in aircraft=20 Sent: Monday, January 05, 2009 5:35 AM Subject: [FlyRotary] Re: 20B install issues overcome Mike,=20 Actually, reducing exhaust noise is one of the beneifts of = turbo-charging. Mark S. On Sun, Jan 4, 2009 at 8:35 PM, Mike Wills wrote: Well when the E-Racer that was built by George Graham was on the = airport it was about the only prop plane louder than mine. That airplane = was ear splitting loud. So I'm not sold on the prop as a noise reducer. = Give yourself more credit Al, you've actually engineered and built a = muffler that works. Mike Wills ----- Original Message -----=20 From: Mark Steitle=20 To: Rotary motors in aircraft=20 Sent: Sunday, January 04, 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 significant reduction. I think I still have the drawings you = provided. The nice thing 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 root of the blades (pusher). It occurs 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 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 Agree. 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. ;-( =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 from inconel, similar to your design. I take it from your = report that your muffler is holding up well? =20 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 that 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,=20 That's a great shot. Have you had any "significant issues" = with your install? If so, how did you overcome them? Mark S. =20 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 first installed in a composite airplane. I had some kind of = electrical noise related corruption of settings which persisted through = a lot of effort for over a years time. It has been resolved, and the = engine running fine. That 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. The theory was that the differential pressure 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 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 eventually install some sort of air = flow 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 quite fortunate = with how well things have worked out. Performance and economy are = great. Al G http://members.cox.net/alg3/airplane.htm ------=_NextPart_000_0018_01C97094.2A2665C0 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
Mike,
Mufflers were never designed to fit = into engine=20 bays because of the size and heat, that's why I have decided to have = mine=20 outside the cowl. The fact that it is designed for cooling air both = internally=20 and externally, and is designed aerodynamically for that, I believe = that's the=20 best place for it. It may be that I can incorporate it into a cowl = design so=20 that it's not too draggy - will just have to wait and see.
BTW Bill Jepson had a big input into = this design,=20 but I have been a long time in proving the design.
George (down under)
----- Original Message -----
From:=20 Mike = Wills
Sent: Tuesday, January 06, 2009 = 12:54=20 PM
Subject: [FlyRotary] Re: 20B = install=20 issues overcome

I thought about it, but that hardware = doesnt fit=20 well in the RV-4 cowl either.
 
Mike
----- Original Message -----
From:=20 Mark=20 Steitle
To: Rotary motors in = aircraft=20
Sent: Monday, January 05, = 2009 5:35=20 AM
Subject: [FlyRotary] Re: 20B = install=20 issues overcome

Mike,
 
Actually, reducing exhaust noise is one of the beneifts of=20 turbo-charging.
 
Mark S.

On Sun, Jan 4, 2009 at 8:35 PM, Mike Wills = <rv-4mike@cox.net> = wrote:
Well when the E-Racer that was = built by=20 George Graham was on the airport it was about the only prop plane = louder=20 than mine. That airplane was ear splitting loud. So I'm not sold = on the=20 prop as a noise reducer. Give yourself more credit Al, you've = actually=20 engineered and built a muffler that works.
 
Mike Wills
----- Original Message ----- =
From: Mark Steitle
To: Rotary motors in=20 aircraft
Sent: Sunday, January 04, = 2009 8:45=20 AM
Subject: [FlyRotary] Re: = 20B=20 install issues overcome

I guess the prop chopping the noise stream could = account=20 for some of the perception of quietness.  As for the=20 muffler/resonator, 6db is a significant reduction.  I think = I still=20 have the drawings you provided.  The nice thing about the=20 tangential muffler design is that it will fit inside my = cowl.  The=20 muffler/resonator should fit where the Hushpower 2 is now.  = We'll=20 see.

Mark

On Sun, Jan 4, 2009 at 10:17 AM, Al = Gietzen <ALVentures@cox.net> wrote:

Subject:=20 [FlyRotary] Re: 20B install issues overcome

 

My exhaust=20 exits about 6-7 inches from prop and goes through near the = root of the=20 blades (pusher). It occurs to me that having my exhaust exit = through=20 the prop may help reduce or mask the exhaust noise.  On a = takeoff=20 roll there is a prop blade breaking that exhaust stream about = 130=20 times per second. Let's see, that's about 1 blade passing for = every=20 two exhaust pulses on the 20B =96 could make a=20 difference.

 

The=20 secondary muffler/resonator I have also helps.  On the = dyno we=20 measured that resulted in about 6 db = reduction.

 

Al=20 G

Agree.  Unfortunately, that's = not a=20 comment I hear.  On the contrary, they usually tell me = that they=20 can hear me before they can see me.  ;-(  =

Mark=20 S.
ANR headsets mandatory

On Sun, = Jan 4, 2009=20 at 12:22 AM, Al Gietzen <ALVentures@cox.net> wrote:

I'm=20 presently gathering materials to fabricate a tangential = muffler made=20 from inconel, similar to your design.  I take it from = your report=20 that your muffler is holding up well?      =   =20

Mark S.

 

So far it=20 is doing fine.  And the inconel tangential and the 321SS=20 secondary muffler (my own design) quiet it down nicely.  = A few=20 days ago I picked up my brother to go for a ride, while my=20 sister-in-law waited and watched other planes come and = go.  When=20 we got back her remark was that my plane was quieter than all = the=20 rest.  I consider that to be 'expert=20 testimony'J.

Al=20 G

On Sat, Jan 3, 2009 at = 5:47 PM,=20 Al Gietzen <ALVentures@cox.net> wrote:

Al,=20

That's a great shot.  Have you had any = "significant=20 issues" with your install?  If so, how did you overcome=20 them?
Mark S. 

I = had 2=20 issues that required some time and determination. The first = was the=20 RWS EC2.  I had an early version for the 3-rotor, and = perhaps the=20 first installed in a composite airplane.  I had some kind = of=20 electrical noise related corruption of settings which = persisted=20 through a lot of effort for over a years time. It has been = resolved,=20 and the engine running fine.  That has been discussed = here more=20 than once in the past.

The other=20 was less-than-expected performance of an oil cooler built into = the=20 wing root, without much of a scoop for the inlet below the = wing.=20  The theory was that the differential pressure = below/above the=20 wing would help provide the necessary air flow.  Not the = case=20 here as the location is too far back on the wing; and behind = the=20 strake (the inboard section on the canard airplane).  The = pressure differential turned out to be only about 1" H20 =96 = very little=20 help.  I added a ram scoop, and installed a small = oil/water heat=20 exchanger in the cowl.  Currently oil temps are fine, and = the=20 coolant temp is running a bit lower than I like at = cruise.  I may=20 eventually install some sort of air flow adjustment, or even = consider=20 installing a thermostat in the engine.  You may recall = discussion=20 of these changes here in the past as well.

I'm just=20 past 140 hours flying time, and feel quite fortunate with how = well=20 things have worked out.  Performance and economy are=20 great.

Al=20 G   http://members.cox.net/alg3/airplane.htm

 

 

 

 



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