X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [208.80.144.20] (HELO mail.royell.org) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTPS id 3884455 for flyrotary@lancaironline.net; Tue, 13 Oct 2009 11:38:09 -0400 Received-SPF: pass receiver=logan.com; client-ip=208.80.144.20; envelope-from=dvanwinkle@royell.org Received: from IBM04421E67337 ([208.80.148.124]) by mail.royell.org (IceWarp 9.4.2) with SMTP id UAE35915 for ; Tue, 13 Oct 2009 10:43:15 -0600 Message-ID: <217DA0BFB345427CBF10FF3BFC319C65@IBM04421E67337> From: "Dean Van Winkle" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Your muffler Date: Tue, 13 Oct 2009 10:37:29 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0017_01CA4BF1.29BB1B10" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5843 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Antivirus: avast! (VPS 091012-0, 10/12/2009), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0017_01CA4BF1.29BB1B10 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable George I went back to Google using the search title "Lockheed Q-Star Aircraft" = and brought up a slightly different first page. Suggest you select three = titles on that page. 1. "Lockheed Q-Star" This shows the aircraft flying along the coast = with the 185 hp Curtiss-Wright engine, a square Corvette radiator in the = nose and an up turned exhaust behind the engine. 2 . "Lockheed Q-Star-Tanner -Hiller Airport" This has several photos = and says the aircraft is for sale. The last photo shows 2 cylinder type = mufflers side by side and the up turned exhaust housed within the engine = fairing.=20 3. "Lockheed Combined Sailplane & Slow Turning Propeller-July '96 = Aviation History Feature". Additional information on the aircraft. A later entry said the aircraft was not for sale. It may be in a museum = by now. I chose not to search the other 14,000 entries under that search = title. Hope this info will help a little bit. Dean Van Winkle=20 ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Tuesday, October 13, 2009 1:09 AM Subject: [FlyRotary] Re: Your muffler Dean,=20 Did you get the details of the muffler? George ( down under) Mike, etal Mid June, 1968, I was employed by the U S Army Aviation Systems Cmd = in St Louis as a Dept of Army Civilian Aeronautical Engineer and = assigned to the Fixed Wing Project Engineering Office. Shortly = thereafter, I was tasked with evaluating several Engineering Change = Proposals on the YO-3A aircraft. Early flight testing had uncovered = some structural weakness in the new retractable main landing gear = installation in the wings that were now repositioned as low wings, and = other areas of the aircraft. This may be common knowledge to most if not = all of you but the eleven YO-3A production all flew with Continental = IO-360 210 hp engines and never with rotary engines. There was a 12 V- = belt reduction driving a 6 blade fixed pitch wooden propeller, later = replaced with 3 blade constant speed wooden propellers. The earlier = quiet development aircraft, the QT-2, the two QT-2 Prize Crew aircraft = that did Operational Evaluation in Vietnam, and the Lockheed Q Star = propeller eval aircraft all had Continental O-200 100hp engines with = reduction drives, high -mounted behind the cockpit, with a long drive = shaft and pylon on the nose supporting the propeller end. The two QT-2 = Prize Crew aircraft had a seat for the observer behind the pilot. The Q = Star had a conventional main landing gear similar to a Cessna 180 and = was the only one to also test the Curtiss-Wright FC2-60 Wankel rotary = engine. The Info came from Google "YO-3A Aircraft" . The header " Quiet = Aircraft Association" was on the first page of Google. The first page of = QAA lists both test engines for the Q Star and a photo collage of all 4 = aircraft is about mid -article. I gave up searching for any further data = on the Curtiss-Wright installation. Dean Van Winkle Slo Build RV-9A '89 -13B, RD-1B, EC2, EM2, = Mistral Intake ----- Original Message -----=20 From: Mike Wills=20 To: Rotary motors in aircraft=20 Sent: Friday, October 09, 2009 9:26 PM Subject: [FlyRotary] Re: Your muffler George, I agree with you on getting the muffler out of the cowl. = But I know there are those that would like to keep it under cowl, and of = course the canard guys probably dont have a choice. For a canard this = could be a good way to go. There's a youtube video from a guy restoring a YO-3A up in the LA = area. It's pretty dry but a minute in there is a shot of the exhaust = system unfaired. I'd like to know what if anything is in that muffler at = the front. Behind that muffler is what the guy refers to as a "piccolo = tube" which is also enclosed in the fairing. The fairing and the = fuselage side are lined with absorbant material held in place with a = metal screen. http://www.youtube.com/watch?v=3DrIhK8PWRMbI Mike Wills RV-4 N144MW ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Friday, October 09, 2009 2:12 PM Subject: [FlyRotary] Re: Your muffler Thanks Mike, For your kind comments, but I must emphasize that this design = is designed primarily for outside cowl use. I understand that this, to = some people, might give rise to concerns of extra drag - but to my mind = anything to get the heat out of the cowl. For my own design I envisage the muffler sitting within a half = circle recess formed in the cowl, but there no reason that it can't sit = behind the cowl under the fuselage. If your talking about the long under fuselage design which = forms part of the fuselage, I must admit I like that design as well. The = longer the better in my opinion, you could string a number of light = weight mufflers along a line, each feeing into the next with cooling air = mixing in, as well as cooling the OD. That would be super quiet. I = notice the best muffling ( to date) is done with more than one muffler = i.e. a primary and a secondary. I'm not trying to convince anyone this is the best design, = merely putting it up for possible solution to the problem. As you and = others have said, off-the-shelf types aren't lasting anywhere near long = enough. Bill Jepson and I laboured over this design for some time, = before we came to the final design, I have been unable to finish my = single so haven't been able to test it yet - but it sure looks good. George ( down under) OK George, my memory is now jogged having seen your drawing. I = liked the design when I saw it the first time but discounted it for my = application because I couldnt see a good way to make any muffler with a = tangential entry fit my airframe. This is the same reason I passed on = Al's proven muffler design. I think the use of cooling airflow introduced into the muffler = makes a lot of sense and this is something your design has in common = with the YO-3A muffler I've been talking about. I believe the YO-3A = design would prove superior by virtue of the greatly increased volume of = the muffler and the use of absorptive materials. Of course until someone builds one and tries it who knows if = it will hold up to the abusive exhaust output of a rotary. But the YO-3A = design does have the advantage of being flight proven in a pretty tough = environment - low altitude recon in Vietnam. Your muffler design (or Al's) is a winner if the goal is to = keep the muffler within the confines of the cowl. My cowl is already too = tight without a muffler in it. Mike Wills RV-4 N144MW=20 ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Thursday, October 08, 2009 9:18 PM Subject: [FlyRotary] Re: Your muffler Al, Not tested yet, but have one almost complete for the single. The cones are there to stop the sound waves having a direct = line of sight out the rear end, the sound waves will be going all over = the place within the exhaust and I tried to replicate that with the zig = zaggy lines. There is no restriction as the area around the back to back = cones, is equal to the area of the 2" exhaust manifold area. However I do take your point on swirl restriction, but I = don't see a problem as it will swirl out the end, whereas sound waves = travel in a straight line ( I think). Bill did have me put in a = reflector plate opposite the incoming exhaust, but I don't know if this = will interrupt the swirl motion, I suspect it might. The reflector plate = is on the LHS of the parts count - photo attached. George ( down under) George; Nice design. Has anyone run one of these yet. My concern with the tangential muffler is something called = 'swirl flow choking' - discovered in connection with a similar attempt = with gas turbine exhaust. High circumferential velocity tends to keep = the flow from moving out the end, and consequent pressure buildup. I = don't know whether it applies to the pulsed flow, but it might, and your = conical restriction toward the outlet could make it worse.=20 To avoid that possibility in my tangential muffler I added = internal vanes at a 45 degree angle opposite the ports, and extended the = header pipes into muffler to a squared end. Disrupts the circumferential = flow and helps direct the exhaust toward the exit. Your depiction of the idealized sounds waves going = axially; ah-h, well; maybe/maybe notJ. Al G -----Original Message----- From: Rotary motors in aircraft = [mailto:flyrotary@lancaironline.net] On Behalf Of George Lendich Sent: Thursday, October 08, 2009 1:14 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Your muffler Kelly There you go matey. All off the shelf SS cones and tube. George ( down under) ----- Original Message -----=20 From: Kelly Troyer=20 To: Rotary motors in aircraft=20 Sent: Thursday, October 08, 2009 9:32 PM Subject: [FlyRotary] Your muffler George, Do you have a photo or drawing available of your = muffler design..........I seem to remember seeing some design info in the past but do not = know where to find it...... Thanks, -- Kelly Troyer=20 "Dyke Delta"_13B ROTARY Engine=20 "RWS"_RD1C/EC2/EM2=20 "Mistral"_Backplate/Oil Manifold=20 =20 -------------- Original message from "George Lendich" = : --------------=20 > Ed,=20 > Cones are the GO.=20 >=20 > Any bare edge will take a battering from the heat = and shock waves. Cones=20 > formed back to back eliminate any edges.=20 >=20 > There must be supporting structure for the cones, = I've used 1/4" solid=20 > round bar welded into the exhaust skin.=20 > George (down under)=20 -------------------------------------------------------------------- -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html ------=_NextPart_000_0017_01CA4BF1.29BB1B10 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
George
 
I went back to Google using the search = title=20 "Lockheed Q-Star Aircraft" and brought up a slightly different first = page.=20 Suggest you select three titles on that page.
 
1.  "Lockheed Q-Star"   = This shows=20 the aircraft flying along the coast with the 185 hp Curtiss-Wright = engine, a=20 square Corvette radiator in the nose and an up turned exhaust behind the = engine.
 
2 .  "Lockheed Q-Star-Tanner = -Hiller=20 Airport"   This has several photos and says the aircraft is = for sale.=20 The last photo shows 2 cylinder type mufflers side by side and the = up=20 turned exhaust housed within the engine fairing. 
 
3.   "Lockheed Combined = Sailplane &=20 Slow Turning Propeller-July '96 Aviation History Feature".  = Additional=20 information on the aircraft.
 
A later entry said the aircraft was not = for=20 sale.  It may be in a museum by now. I chose not to search the = other 14,000=20 entries under that search title.  Hope this info will help a little = bit.
 
Dean Van Winkle 
 
 
 
 
----- Original Message -----
From:=20 George=20 Lendich
Sent: Tuesday, October 13, 2009 = 1:09=20 AM
Subject: [FlyRotary] Re: Your=20 muffler

 
Dean,
Did you get the details of the = muffler?
George ( down under)
 
Mike, etal
 
Mid June, 1968, I was employed by = the U S Army=20 Aviation Systems Cmd in St Louis as a Dept of Army Civilian = Aeronautical=20 Engineer and assigned to the Fixed Wing Project Engineering Office. = Shortly=20 thereafter, I was tasked with evaluating several Engineering Change=20 Proposals on the YO-3A  aircraft. Early flight testing had = uncovered=20 some structural weakness in the new retractable main landing = gear=20 installation in the wings that were now repositioned as low wings, = and other=20 areas of the aircraft. This may be common knowledge to most if not = all of=20 you but the eleven YO-3A production all flew with Continental IO-360 = 210 hp=20 engines and never with rotary engines. There was a 12 V- belt = reduction=20 driving a 6 blade fixed pitch wooden propeller, later replaced=20 with 3 blade constant speed = wooden=20 propellers. The earlier quiet development aircraft, the QT-2, = the two=20 QT-2 Prize Crew aircraft that did Operational Evaluation in Vietnam, = and the=20 Lockheed Q Star propeller eval aircraft all had Continental O-200 = 100hp=20 engines with reduction drives, high -mounted behind the = cockpit, with a=20 long drive shaft  and pylon on the nose supporting the = propeller end.=20 The two QT-2 Prize Crew aircraft had a seat for the observer behind = the=20 pilot. The Q Star had a conventional main landing gear similar to a = Cessna=20 180 and was the only one to also test the Curtiss-Wright = FC2-60=20 Wankel rotary engine. The Info came from Google "YO-3A = Aircraft" .=20 The header " Quiet Aircraft Association" was on the first page of = Google.=20 The first page of QAA lists both test engines for the Q Star and a = photo=20 collage of all 4 aircraft is about mid -article. I gave up searching = for any=20 further data on the Curtiss-Wright installation.
 
Dean Van Winkle   Slo = Build=20 RV-9A  '89 -13B, RD-1B, EC2, EM2, Mistral Intake
----- Original Message ----- =
From:=20 Mike = Wills=20
To: Rotary motors in = aircraft=20
Sent: Friday, October 09, = 2009 9:26=20 PM
Subject: [FlyRotary] Re: = Your=20 muffler

George, I agree with you on = getting the=20 muffler out of the cowl. But I know there are those that would = like to=20 keep it under cowl, and of course the canard guys probably dont = have a=20 choice. For a canard this could be a good way to go.
 
There's a youtube video from a = guy restoring=20 a YO-3A up in the LA area. It's pretty dry but a minute in there = is a shot=20 of the exhaust system unfaired. I'd like to know what if anything = is in=20 that muffler at the front. Behind that muffler is what the guy = refers to=20 as a "piccolo tube" which is also enclosed in the fairing. The = fairing and=20 the fuselage side are lined with absorbant material held in place = with a=20 metal screen.
 
http://www.youtube.= com/watch?v=3DrIhK8PWRMbI
 
Mike Wills
RV-4 N144MW
----- Original Message ----- =
From:=20 George=20 Lendich
To: Rotary motors in = aircraft=20
Sent: Friday, October 09, = 2009 2:12=20 PM
Subject: [FlyRotary] Re: = Your=20 muffler

 
Thanks Mike,
For your kind comments, but I = must=20 emphasize that this design is  designed primarily for = outside=20 cowl use. I understand that this, to some people, might give = rise to=20 concerns of extra drag - but to my mind anything to get the = heat out=20 of the cowl.
 
For my own design I envisage = the muffler=20 sitting within a half circle recess formed in the cowl, but = there no=20 reason that it can't sit behind the cowl under the = fuselage.
 
If your talking about the long = under=20 fuselage design which forms part of the fuselage, I must admit = I like=20 that design as well. The longer the better in my opinion, you = could=20 string a number of light weight mufflers along a line, each = feeing=20 into the next with cooling air mixing in,  as well as = cooling the=20 OD. That would be super quiet. I notice the best muffling ( to = date)=20 is done with more than one muffler i.e. a primary and a=20 secondary.
 
I'm not trying to convince = anyone this=20 is the best design, merely putting it up for possible solution = to the=20 problem.  As you and others have = said, off-the-shelf=20 types aren't lasting anywhere near long enough. Bill Jepson = and I=20 laboured over this design for some time, before we came to the = final=20 design, I have been unable to finish my single so haven't been = able to=20 test it yet - but it sure looks good.
 
George ( down under)
 
OK George, my memory is now = jogged having=20 seen your drawing. I liked the design when I saw it the first = time but=20 discounted it for my application because I couldnt see a = good way=20 to make any muffler with a tangential entry fit my airframe. = This is=20 the same reason I passed on Al's proven muffler = design.
 
I think the use of cooling = airflow=20 introduced into the muffler makes a lot of sense and this is = something=20 your design has in common with the YO-3A muffler I've been = talking=20 about. I believe the YO-3A design would prove superior by = virtue of=20 the greatly increased volume of the muffler and the use of = absorptive=20 materials.
 
Of course until someone = builds one and=20 tries it who knows if it will hold up to the abusive exhaust = output of=20 a rotary. But the YO-3A design does have the advantage of = being flight=20 proven in a pretty tough environment - low altitude = recon in=20 Vietnam.
 
Your muffler design (or Al's) = is a=20 winner if the goal is to keep the muffler within the confines = of the=20 cowl. My cowl is already too tight without a muffler in=20 it.
 
Mike Wills
RV-4 = N144MW 
----- Original Message ----- =
From:=20 George Lendich =
To: Rotary motors in = aircraft
Sent: Thursday, = October 08,=20 2009 9:18 PM
Subject: [FlyRotary] = Re: Your=20 muffler

Al,
Not tested yet, but have = one almost=20 complete for the single.
 
The cones are there to stop = the sound=20 waves having a direct line of sight out the rear end, = the sound=20 waves will be going all over the place within the exhaust = and I=20 tried to replicate that with the zig zaggy = lines.
 
There is no restriction as = the area=20 around the back to back cones, is equal to the area of the = 2"=20 exhaust manifold area.
 
However I do take your = point on swirl=20 restriction, but I don't see a problem as it will swirl out = the end,=20 whereas sound waves travel in a straight line ( I=20 think).  Bill did = have me put in=20 a reflector plate opposite the incoming exhaust, but I don't = know if=20 this will interrupt the swirl motion, I suspect it might. = The=20 reflector plate is on the LHS of the parts count = - photo=20 attached.
 
George ( down = under)

George;

 

Nice=20 design.  Has anyone run one of these = yet.

My=20 concern with the tangential muffler is something called = =91swirl=20 flow choking=92 =96 discovered in connection with a = similar attempt=20 with gas turbine exhaust.  High circumferential = velocity=20 tends to keep the flow from moving out the end, and = consequent=20 pressure buildup.  I don=92t know whether it applies = to the=20 pulsed flow, but it might, and your conical restriction = toward the=20 outlet could make it worse.

 

To=20 avoid that possibility in my tangential muffler I added = internal=20 vanes at a 45 degree angle opposite the ports, and = extended the=20 header pipes into muffler to a squared end. Disrupts the=20 circumferential flow and helps direct the exhaust toward = the=20 exit.

 

Your=20 depiction of the idealized sounds waves going axially; = ah-h, well;=20 maybe/maybe notJ.

 

Al=20 G

 

-----Original=20 Message-----
From: Rotary motors = in=20 aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of George = Lendich
Sent:=20 Thursday, October 08, 2009 1:14 PM
To: Rotary motors = in=20 aircraft
Subject:=20 [FlyRotary] Re: Your muffler

 

Kelly

There you=20 go matey. All off the shelf SS cones and=20 tube.

George (=20 down under)

-----=20 Original Message -----

From: Kelly=20 Troyer

To: Rotary = motors in=20 aircraft

Sent: Thursday, = October=20 08, 2009 9:32 PM

Subject: = [FlyRotary] Your=20 muffler

 

 =20 George,

   Do you have a = photo or=20 drawing available of your muffler design..........I seem = to

remember seeing some design = info in the=20 past but do not know where to find=20 it......

 

 

Thanks,

--
Kelly Troyer
"Dyke = Delta"_13B=20 ROTARY Engine
"RWS"_RD1C/EC2/EM2 =
"Mistral"_Backplate/Oil=20 Manifold


 

-------------- Original = message from=20 "George Lendich" <lendich@aanet.com.au>: = --------------=20


> Ed,
> Cones are the GO. =
>=20
> Any bare edge will take a battering from the = heat and=20 shock waves. Cones
> formed back to back = eliminate any=20 edges.
>
> There must be supporting = structure=20 for the cones, I've used 1/4" solid
> round bar = welded=20 into the exhaust skin.
> George (down under)=20 =

--
Homepage:  = http://www.flyrotary.com/
Archive=20 and UnSub:  =20 = http://mail.lancaironline.net:81/lists/flyrotary/List.html
------=_NextPart_000_0017_01CA4BF1.29BB1B10--