Return-Path: Received: from relay02.roc.ny.frontiernet.net ([66.133.131.35] verified) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 3048866 for flyrotary@lancaironline.net; Fri, 27 Feb 2004 23:29:11 -0500 Received: (qmail 10695 invoked from network); 28 Feb 2004 04:29:10 -0000 Received: from unknown (HELO frontiernet.net) ([170.215.99.215]) (envelope-sender ) by relay02.roc.ny.frontiernet.net (FrontierMTA 2.3.6) with SMTP for ; 28 Feb 2004 04:29:10 -0000 Message-ID: <4040191C.2C483813@frontiernet.net> Date: Fri, 27 Feb 2004 22:29:16 -0600 From: Jim Sower X-Mailer: Mozilla 4.77 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: FW: [VAF Mailing List] Engine Choice References: Content-Type: multipart/alternative; boundary="------------2042CABBD7415EFCDDA36E97" --------------2042CABBD7415EFCDDA36E97 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Yeah. Also, I believe Tracy has answered all of his "questions" around tortionals and props and dynos. Additionally, if there were problems, Tracy would have encountered one in 1500 hrs. The guy's statement around "... sprag clutches cause the prop to freewheel in the event of engine failure putting the equivalent of a barn door (HUGE drag compared to stopped prop) behind the airplane ..." is so preposterous that it calls ALL of his other engineering into question. His article sounds authoritative, but has all the intellectual allure of Lamar's rantings that NACA ducts and Electric Water Pumps "... cannot possibly work ....". Stick with Tracy. He has something flying. This guy has nada. Just a theory .... Jim S. David Leonard wrote: > Yes, you should read Tracy’s discussion. Also remember that > the author of the post you sent was trying to sell the > Powersport PSRU (for $6000 I might add). Interesting also > that to my knowledge the PSRU that has truly failed were the > early Powersport PSRU. > > “Bill” implies that because the rotaries pulse is different > from other engines it is somehow more damaging. The reality > is that the pulse from the rotary is must softer and lasts for > a longer angular portion of the rotation of the e-shaft. This > makes the rotary much easier on a PSRU than a 4cylinder > piston. > > I suspect (thought I have no evidence) that Powersport > neglected to counterbalance their engine in the early testing > that “Bill” mentions. > > Dave Leonard > --------------2042CABBD7415EFCDDA36E97 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Yeah.  Also, I believe Tracy has answered all of his "questions" around tortionals and props and dynos.  Additionally, if there were problems, Tracy would have encountered one in 1500 hrs.

The guy's statement around "... sprag clutches cause the prop to freewheel in the event of engine failure putting the equivalent of a barn door (HUGE drag compared to stopped prop) behind the airplane ..." is so preposterous that it calls ALL of his other engineering into question.  His article sounds authoritative, but has all the intellectual allure of Lamar's rantings that NACA ducts and Electric Water Pumps "... cannot possibly work ...".  Stick with Tracy.  He has something flying.  This guy has nada.

Just a theory .... Jim S.

David Leonard wrote:

Yes, you should read Tracy’s discussion.  Also remember that the author of the post you sent was trying to sell the Powersport PSRU (for $6000 I might add).  Interesting also that to my knowledge the PSRU that has truly failed were the early Powersport PSRU. 

“Bill” implies that because the rotaries pulse is different from other engines it is somehow more damaging.  The reality is that the pulse from the rotary is must softer and lasts for a longer angular portion of the rotation of the e-shaft.  This makes the rotary much easier on  a PSRU than a 4cylinder piston.

I suspect (thought I have no evidence) that Powersport neglected to counterbalance their engine in the early testing that “Bill” mentions.

Dave Leonard

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