X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from wproxy.gmail.com ([64.233.184.201] verified) by logan.com (CommuniGate Pro SMTP 5.0.8) with ESMTP id 972946 for flyrotary@lancaironline.net; Mon, 06 Feb 2006 19:57:33 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.233.184.201; envelope-from=russell.duffy@gmail.com Received: by wproxy.gmail.com with SMTP id 69so1147140wra for ; Mon, 06 Feb 2006 16:56:48 -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:x-mimeole:in-reply-to; b=OI+ch8WDR6bgcUpIGrV5CKMva4MvQxSPkKdiXGv7za315zJfdRqVATz9WgR44jifFtKfslCMykg+gXJi5LvuVb7RvUingVXy7Gc2rjRqyc0o++CUykBFLdqXw51mLS5NdMQibYcii8iC4dOvyUNiRzhUG4YA4r3CJYefF9kzBac= Received: by 10.54.86.12 with SMTP id j12mr497767wrb; Mon, 06 Feb 2006 16:56:48 -0800 (PST) Return-Path: Received: from rd ( [65.6.194.9]) by mx.gmail.com with ESMTP id 39sm8585786wrl.2006.02.06.16.56.46; Mon, 06 Feb 2006 16:56:47 -0800 (PST) From: "Russell Duffy" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Single rotor smooth as silk now Date: Mon, 6 Feb 2006 18:56:46 -0600 Message-ID: <010201c62b81$5f36cbc0$6101a8c0@rd> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0103_01C62B4F.149C5BC0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2670 In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_0103_01C62B4F.149C5BC0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable There are two issues to cope with, one is resonances and the other is transferring the torque pulses. The torque pulses are transferred = completely in a indefinitly stiff system. We do not want that, because of the = internal forces involved. That leaves the resonances created by coupling and = element flexing properties. I believe the only way to stay out of the resonances = is to keep them low. This is what ROTAX is doing, a 582 has gear rattling around idle. When you watch a ROTAX starting up it is very obvious when = the rattling occurs. I have not observed any rattle on my C-Box with the = SOOB.=20 =20 Thanks Richard. =20 =20 The 912S that was originally on the plane had a bad rattle problem. If = you didn't get it above about 2000 rpm on initial start, you couldn't = accelerate out of it. You just had to shut down, and try again. That engine = didn't have the "slipper clutch" that came out as a mod for that problem. =20 =20 I'm looking forward to playing with all this eventually, as it will be a neat project. =20 =20 Rusty =20 ------=_NextPart_000_0103_01C62B4F.149C5BC0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message
There are two issues to cope = with, one is=20 resonances and the other is transferring the torque pulses. The torque = pulses=20 are transferred completely in a indefinitly stiff system. We do not want = that,=20 because of the internal forces involved. That leaves the resonances = created by=20 coupling and element flexing properties. I believe the only way to stay = out of=20 the resonances is to keep them low. This is what ROTAX is doing, a 582 = has gear=20 rattling around idle. When you watch a ROTAX starting up it is very = obvious when=20 the rattling occurs. I have not observed any rattle on my C-Box with the = SOOB. 
 
Thanks=20 Richard.  
 
The 912S that was originally on the plane had a = bad rattle=20 problem. If you didn't get it above about 2000 rpm on initial start, you = couldn't accelerate out of it.  You just had to shut down, and try=20 again.  That engine didn't have the "slipper clutch" that came = out as=20 a mod for that = problem.   
 
I'm looking=20 forward to playing with all this eventually, as it will be a neat = project. =20
 
Rusty
 
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