X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 65 [XX] (49%) URL: contains host with port number (27%) SPAM TRICK: contains gapped text (24%) BODY: contains text similar to "no experience" Return-Path: Received: from [66.219.56.248] (HELO qnsi-xch.qnsi.net) by logan.com (CommuniGate Pro SMTP 5.1.8) with ESMTP id 1981772 for flyrotary@lancaironline.net; Thu, 12 Apr 2007 13:11:56 -0400 Received-SPF: none receiver=logan.com; client-ip=66.219.56.248; envelope-from=bhughes@qnsi.net X-MimeOLE: Produced By Microsoft Exchange V6.5.6944.0 Content-class: urn:content-classes:message Return-Receipt-To: "Bobby J. Hughes" MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Disposition-Notification-To: "Bobby J. Hughes" Subject: RE: [FlyRotary] Re: Mount offset Date: Thu, 12 Apr 2007 12:12:09 -0600 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [FlyRotary] Re: Mount offset Thread-Index: Acd9KdKUmO79RRc5QoexFX5xR/1S/wAA52uw From: "Bobby J. Hughes" To: "Rotary motors in aircraft" Ed, Since the RV10 is matched drilled I am not sure how the vertical fin is positioned. But I figure Van's took all of these items in to consideration during the design process. No point in reinventing the offsets. No jokes.... Is your ball out to the left or right? Bobby=20 -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ed Anderson Sent: Thursday, April 12, 2007 7:45 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Mount offset Hi Bobby, When I designed my original motor mount for a 2.17 gear ratio I offset it 5/8" to the left. Now that I have a 2.85 (opposite prop rotation), I still fly with it offset the same. The only place where I notice this "incorrect"=20 offset really gets my attention is on take off. I could really use the prop pointing slightly to the right instead of the left. In cruise at 170 MPH TAS it is within 1/2 ball. My vertical fin has not offset. Personally, if I were to do the motor mount again, I think I would shoot for 0 deg offset.=20 Just my 0.02 worth Ed ----- Original Message ----- From: "Bobby J. Hughes" To: "Rotary motors in aircraft" Sent: Thursday, April 12, 2007 9:27 AM Subject: [FlyRotary] Re: Mount offset I did say simple and no I am done with geometry :) -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Ernest Christley Sent: Wednesday, April 11, 2007 8:03 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Mount offset Lehanover@aol.com wrote: > > With no experience at all in this area, I had imagined that the engine > would be turned about a vertical line through the prop flange. This, > to induce the required side thrust while keeping the spinner back > plate centered over the hole in the cowling. > > Lynn E. Hanover > This will have very little to do with RVs, but John Dyke specifies 2/3rd of one degree right thrust on the Dyke Delta. That is hinged at the prop flange. He also specifies 1.5 degree upthrust, but that is hinged at the firewall. Bobby, a better way to measure the offset is to break out the old geometry book and calculate the offset. The sin(1.25)x47" is 1.02". The end of the engine will move off center by a long inch. You won't be able to read 1/4 degree on most protractors, but an inch is easy to make out. --=20 ,|"|"|, Ernest Christley | ----=3D=3D=3D<{{(oQo)}}>=3D=3D=3D---- Dyke Delta Builder | o| d |o http://ernest.isa-geek.org | -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html -- Homepage: http://www.flyrotary.com/ Archive and UnSub:=20 http://mail.lancaironline.net:81/lists/flyrotary/List.html=20 -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html