X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from wproxy.gmail.com ([64.233.184.207] verified) by logan.com (CommuniGate Pro SMTP 5.0.7f) with ESMTP id 956747 for flyrotary@lancaironline.net; Fri, 27 Jan 2006 19:50:51 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.233.184.207; envelope-from=russell.duffy@gmail.com Received: by wproxy.gmail.com with SMTP id 37so782353wra for ; Fri, 27 Jan 2006 16:50:07 -0800 (PST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:from:to:subject:date:message-id:mime-version:content-type:x-priority:x-msmail-priority:x-mailer:importance:in-reply-to:x-mimeole; b=IGTGWNgmnxZQbGCTLvtE0hD1EQYf0Vq2wRV9HkmIfn00OvzufDXP7ll5of4fvd2g9UuQcuYz3J+AHiJTQjYu3WNa6m6MgcwSgNEEIu3bXddfU5vOTwWRXj/R5X+eUgK2jrjSwH1oMva0/rwarbFxfixC53M0tQfRmb4pFQ1BGzU= Received: by 10.54.132.19 with SMTP id f19mr4138134wrd; Fri, 27 Jan 2006 16:50:07 -0800 (PST) Return-Path: Received: from rd ( [65.6.194.9]) by mx.gmail.com with ESMTP id g2sm1473102wra.2006.01.27.16.50.06; Fri, 27 Jan 2006 16:50:06 -0800 (PST) From: "Russell Duffy" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Guru - single rotor Date: Fri, 27 Jan 2006 18:50:06 -0600 Message-ID: <009c01c623a4$c82e15f0$6101a8c0@rd> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_009D_01C62372.7D93A5F0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2527 This is a multi-part message in MIME format. ------=_NextPart_000_009D_01C62372.7D93A5F0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable I know you and maybe others are interested in single developments, so I spread the information. =20 Hi George, Thanks, always interested in hearing about this stuff. I noticed that Atkins has single rotors listed for marine applications, but no mention = that I can find of any aircraft usage His belt drive is nowhere to be found either, but the web site is pretty darn disorganized, so it's hard to be sure. =20 I only just recently discovered they were looking at the single and I offered to help, but their well down the track as they have done a = couple before for people, but they had none of the problems you are seeing - I still feel it's fundamentally a problem with balancing of the rotating components, but it could be a need for a heaver flywheel and I suggested that to GURU. As they build for all manual applications it's something = they may not see.=20 Well, I'm quite certain that the balancing is just fine. The problem = seems to be due to the torque reversals, and the lack of any significant = flywheel weight, or dampener. The flywheel weight would work, but it's the = brute force way to solve the problem. There really needs to be a dampener = that can smooth out the pulses, before they get a chance to excite the = natural frequency of the prop assembly. =20 I've spent almost no time looking at this, since it's not my current priority, but eventually, I plan to look at what sort of dampener is = used on the single cylinder two stroke engines. It looks like they would have nearly the same problem with torque reversals, and there have been = plenty of single cylinder 2 stroke engines flown. =20 Cheers, Rusty (got most of the panel stuff, engine and leather interior on the = way, but no RV-8 yet) =20 =20 ------=_NextPart_000_009D_01C62372.7D93A5F0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message

I know you and maybe others are = interested in single=20 developments, so I spread the information.  

Hi George,

Thanks, always interested in hearing about this = stuff.  I=20 noticed that Atkins has single rotors listed for marine = applications, but=20 no mention that I can find of any aircraft usage  His belt = drive is=20 nowhere to be found either, but the web site is pretty darn = disorganized, so=20 it's hard to be sure.  

I only just recently discovered they = were looking at=20 the single and I offered to help, but their well down the track as they = have=20 done a couple before for people, but they had none of the problems you = are=20 seeing - I still feel it's fundamentally a problem with balancing of the = rotating components, but it could be a need for a heaver flywheel and I=20 suggested that to GURU. As they build for all manual applications it's = something=20 they may not see. 

Well, I'm quite certain that the balancing is just = fine.  The=20 problem seems to be due to the torque reversals, and the lack = of=20 any significant flywheel weight, or dampener.  =  The flywheel weight would work, but it's the = brute force=20 way to solve the problem.  There really needs to be a dampener that = can=20 smooth out the pulses, before they get a chance to excite the natural = frequency=20 of the prop assembly. 

I've spent almost no time looking at this, since it's not my = current=20 priority, but eventually, I plan to look at what sort of dampener is = used on the=20 single cylinder two stroke engines.  It looks like they would have = nearly=20 the same problem with torque reversals, and there have been plenty of = single=20 cylinder 2 stroke engines=20 flown.    

Cheers,
Rusty (got most of the panel=20 stuff, engine and leather interior on the way, but no RV-8=20 yet)  
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