X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtp0v2.neonova.net ([137.118.16.31] verified) by logan.com (CommuniGate Pro SMTP 6.0.6) with ESMTP id 6430855 for flyrotary@lancaironline.net; Sat, 17 Aug 2013 16:41:32 -0400 Received-SPF: pass receiver=logan.com; client-ip=137.118.16.31; envelope-from=res12@fairpoint.net Received: from localhost (localhost [127.0.0.1]) by smtp0v2.neonova.net (Postfix) with ESMTP id BA08FC00D55 for ; Sat, 17 Aug 2013 16:40:57 -0400 (EDT) X-Virus-Scanned: amavisd-new at av-mx.com Received: from smtp0v2.neonova.net ([127.0.0.1]) by localhost (smtp0v2.neonova.net [127.0.0.1]) (amavisd-new, port 10124) with ESMTP id KQl9tOlQfgoo for ; Sat, 17 Aug 2013 16:40:56 -0400 (EDT) Received: from MAIN (dflo-66-243-230-95.gtcom.net [66.243.230.95]) (Authenticated sender: res12@fairpoint.net) by smtp0v2.neonova.net (Postfix) with ESMTPA for ; Sat, 17 Aug 2013 16:40:56 -0400 (EDT) Message-ID: From: "Richard Sohn" To: "Rotary motors in aircraft" References: In-Reply-To: Subject: Re: [FlyRotary] Re: Single Rotor Update Date: Sat, 17 Aug 2013 15:40:47 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0040_01CE9B60.24DE30B0" X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 16.4.3508.205 X-MimeOLE: Produced By Microsoft MimeOLE V16.4.3508.205 This is a multi-part message in MIME format. ------=_NextPart_000_0040_01CE9B60.24DE30B0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable This happens when the pressure regulator is using ambient pressure only = for reference. The TBI is using a reference pressure probe picking up = dynamic pressure in the intake for increasing fuel flow at high power = settings. I ran it with ambient only at one time, and saw exactly what = you are describing.=20 Now I do not see the leaning out at WOT as I have seen on all the float = carburetors I have tested. For example a 38mm would do fine at up to 60% = power settings but will start leaning out higher up. A 42mm did fine at = WOT, but I could not get it to idle right. Looking at the = specifications, a 38mm carb is rated for up to 65hp only. This is the = range of acceptable mixture consistency. Some carburetors are using = boost valves at WOT against leaning. It looks to me like the rotary is causing higher peak intake velocities = compared to piston engines, and carburetors don=E2=80=99t like that very = much as far as operating range is concerned.=20 Richard Sohn N2071U http://www.fairpoint.net/~res12/home.html From: Ed Anderson=20 Sent: Saturday, August 17, 2013 9:54 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Single Rotor Update I have a friend who tried an Ellison on a 13B. Never could get the low = end and the high end fuel flow to work together (I think the airflow = range for the rotary exceeded the model he was using). =20 In any case, it finally failed him, destroyed his aircraft in the crash = landing, but fortunately came through with no physical damage to the = pilot. When he set the Ellison up so it would idle OK, he ran out of = fuel flow on the high end. When he set if so the high end flow was = good, he had too much fuel on the low end. Never did sort it out. Ed From: Richard Sohn=20 Sent: Saturday, August 17, 2013 9:53 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Single Rotor Update I am not really sure what is causing the problem, since some of the = interior can not be opened without causing damage to crimps. From what = can be seen from the outside and the results of my observations, I think = there is insufficient air bleeding in the section between the pressure = regulator and the spray tube, which is affecting fuel flow continuity = under certain condition. There is no information available as of the difference of the physical = lay out form the original Ellison carb.=20 I realize that I do not have a good case for functional reliability, but = I have don extensive investigation on the test stand, which clearly = identified the area of concern so I can stay away from it. By the way, after a couple of emails with ROTEC there was just silence = from their side. Richard Sohn N2071U http://www.fairpoint.net/~res12/home.html From: Ed Anderson=20 Sent: Saturday, August 17, 2013 8:04 AM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: Single Rotor Update So Richard, Why causes the problem with the origination orientation of the TB = =E2=80=93 does the jet leak, fail to fee fuel in that orientation = =E2=80=93 airflow problem? Ed From: Richard Sohn=20 Sent: Friday, August 16, 2013 10:44 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Single Rotor Update Another update, hopefully the last one on the engine. The problem with the ROTEC TBI (Ellison) has been solved. It turned out = that a statement by the manufacturer is not fully correct, if not = misleading. My problem was engine cut out at WOT. This only occurred at high speed = taxi, not on the test stand. ROTEC statement:=E2=80=9D Because the TBI has no float bowl, it will = work in any orientation, even upside down=E2=80=9D =20 I found out that if the slide throttle is horizontal in a side draft = configuration, you can encounter the problems I had.=20 The problem showed up, with the slide throttle 5deg down at the = =E2=80=9Copen=E2=80=9D end. This is the difference between the = horizontal orientation on my test stand and the installation in the tail = dragger on the ground. I solved the problem with orienting the TBI 45deg up on the = =E2=80=9Copen=E2=80=9D end, after testing all variants I could imagine. = This change included a unique double acting Bowden cable throttle.=20 The last two straight TOL worked flawless. Richard Sohn N2071U http://www.fairpoint.net/~res12/home.html -------------------------------------------------------------------------= ------- -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html -------------------------------------------------------------------------= ------- No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3392 / Virus Database: 3211/6583 - Release Date: = 08/16/13 No virus found in this message. Checked by AVG - www.avg.com Version: 2013.0.3392 / Virus Database: 3211/6585 - Release Date: = 08/17/13 ------=_NextPart_000_0040_01CE9B60.24DE30B0 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
This happens when the pressure regulator is using ambient pressure = only for=20 reference. The TBI is using a reference pressure probe picking up = dynamic=20 pressure in the intake for increasing fuel flow at high power settings. = I ran it=20 with ambient only at one time, and saw exactly what you are describing. =
Now I do not see the leaning out at WOT as I have seen on all the = float=20 carburetors I have tested. For example a 38mm would do fine at up to 60% = power=20 settings but will start leaning out higher up. A 42mm did fine at WOT, = but I=20 could not get it to idle right. Looking at the specifications, a 38mm = carb is=20 rated for up to 65hp only. This is the range of acceptable mixture = consistency.=20 Some carburetors are using boost valves at WOT against leaning.
It looks to me like the rotary is causing higher peak intake = velocities=20 compared to piston engines, and carburetors don=E2=80=99t like that very = much as far as=20 operating range is concerned.
 
Richard=20 Sohn
N2071U

http://www.fairpoint.net/~res12/home.html
 
Sent: Saturday, August 17, 2013 9:54 AM
Subject: [FlyRotary] Re: Single Rotor = Update
 
I have a friend who tried an Ellison on a 13B.  Never could = get the=20 low end and the high end fuel flow to work together (I think the airflow = range=20 for the rotary exceeded the model he was using). 
 
In any case, it finally failed him, destroyed his aircraft in the = crash=20 landing, but fortunately came through with no physical damage to the=20 pilot.  When he set the Ellison up so it would idle OK, he ran out = of fuel=20 flow on the high end.  When he set if so the high end flow was = good, he had=20 too much fuel on the low end.  Never did sort it out.
 
Ed
 
Sent: Saturday, August 17, 2013 9:53 AM
Subject: [FlyRotary] Re: Single Rotor = Update
 
I am not really sure what is causing the problem, since some of the = interior can not be opened without causing damage to crimps. From what = can be=20 seen from the outside and the results of my observations, I think there = is=20 insufficient air bleeding in the section between the pressure regulator = and the=20 spray tube, which is affecting fuel flow continuity under certain=20 condition.
There is no information available as of the difference of the = physical lay=20 out form the original Ellison carb.
I realize that I do not have a good case for functional = reliability, but I=20 have don extensive investigation on the test stand, which clearly = identified the=20 area of concern so I can stay away from it.
 
By the way, after a couple of emails with ROTEC there was just = silence from=20 their side.
 
Richard=20 Sohn
N2071U

http://www.fairpoint.net/~res12/home.html
 
Sent: Saturday, August 17, 2013 8:04 AM
Subject: [FlyRotary] Re: Single Rotor = Update
 
So Richard,
 
Why causes the problem with the origination orientation of the = TB  =E2=80=93=20 does the jet leak, fail to fee fuel in that orientation =E2=80=93 = airflow problem?
 
Ed
 
Sent: Friday, August 16, 2013 10:44 PM
Subject: [FlyRotary] Single Rotor Update
 
Another update, hopefully the last one on the engine.
 
The problem with the ROTEC TBI (Ellison) has been solved. It turned = out=20 that a statement by the manufacturer is not fully correct, if not=20 misleading.
My problem was engine cut out at WOT. This only occurred at high = speed=20 taxi, not on the test stand.
 
ROTEC statement:=E2=80=9D Because the TBI has no float bowl, it = will work in any=20 orientation, even upside down=E2=80=9D 
I found out that if the slide throttle is horizontal in a side = draft=20 configuration, you can encounter the problems I had.
 
The problem showed up, with the slide throttle 5deg down at the = =E2=80=9Copen=E2=80=9D end.=20 This is the difference between the horizontal orientation on my test = stand and=20 the installation in the tail dragger on the ground.
 
I solved the problem with orienting the TBI 45deg up on the = =E2=80=9Copen=E2=80=9D end,=20 after testing all variants I could imagine. This change included a = unique double=20 acting Bowden cable throttle.
The last two straight TOL  worked flawless.
 
Richard=20 Sohn
N2071U

http://www.fairpoint.net/~res12/home.html
 

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

No virus found in this=20 message.
Checked by AVG - www.avg.com
Version: 2013.0.3392 / = Virus=20 Database: 3211/6583 - Release Date:=20 08/16/13

No virus found in this=20 message.
Checked by AVG - www.avg.com
Version: 2013.0.3392 / = Virus=20 Database: 3211/6585 - Release Date:=20 08/17/13

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