Return-Path: Received: from [24.25.9.102] (HELO ms-smtp-03-eri0.southeast.rr.com) by logan.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 3112926 for flyrotary@lancaironline.net; Mon, 22 Mar 2004 11:43:21 -0500 Received: from edward (clt78-020.carolina.rr.com [24.93.78.20]) by ms-smtp-03-eri0.southeast.rr.com (8.12.10/8.12.7) with SMTP id i2MGhIs2027855 for ; Mon, 22 Mar 2004 11:43:19 -0500 (EST) Message-ID: <000801c4102c$c7cd1c10$2402a8c0@edward> From: "Ed Anderson" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: C mounting on a B plate?? Renesis & RD-1Cdrivetesting Date: Mon, 22 Mar 2004 11:43:18 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0005_01C41002.DEBB6AA0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. ------=_NextPart_000_0005_01C41002.DEBB6AA0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable -----=20 From: Tracy Crook=20 To: Rotary motors in aircraft=20 Sent: Monday, March 22, 2004 11:38 AM Subject: [FlyRotary] Re: C mounting on a B plate?? Renesis & = RD-1Cdrivetesting OK, OK, rub it in, but before you guys get carried away, consider the = following: The prop limitation was always my only reservation about using the = higher ratio. I must emphasize that in order for this to work, the prop = must not only be long but has to have a good profile as far down toward = the root as possible with the MUCH higher pitch. I worked with Clark at = Perf. Props and emphasized this. It required a thicker than standard = hub to get close to what was needed. If you don't do these things, all you get is significantly higher rpm, = less performance, higher fuel burn and higher wear. Look at the = numbers from previous users of the 2.85 drive. =20 Did I mention the three spinners, various spinner bulkheads, prop = bolts that were now too short and other various things that went wrong = during the effort to make this work right? Tracy As always the difference is in the attention to details that affect = the operation. Sound like you have the right combination of prop and = gearbox ratio to overcome those limitations. I wonder if a 3 bladed = prop might not be the answer for those prop length challenged. =20 You mentioned seeing 7050 rpm - if at 1000 MSL and 75F OAT if you = were running WOT and rich, that appears to give you right at 200HP out = of your engine. I don't suppose you noticed your fuel burn rate? I = would think it would be around 18 GPH. My calculations indicate around = 18.5 gph. Ed Anderson ------=_NextPart_000_0005_01C41002.DEBB6AA0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
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From:=20 Tracy = Crook
Sent: Monday, March 22, 2004 = 11:38=20 AM
Subject: [FlyRotary] Re: C = mounting on a=20 B plate?? Renesis & RD-1Cdrivetesting

OK, OK, rub it in, but before you guys get carried away, consider = the=20 following:

The prop limitation was always my only reservation about using the = higher=20 ratio.  I must emphasize that in order for this to work, the prop = must=20 not only be long but has to have a good profile as far down toward the = root as=20 possible with the MUCH higher pitch.  I worked with Clark at = Perf. Props=20 and emphasized this.  It required a thicker than standard hub to = get=20 close to what was needed.

If you don't do these things, all you get is significantly higher=20 rpm,  less performance, higher fuel burn and higher wear.  = Look at=20 the numbers from previous users of the 2.85 drive.  

Did I mention the three spinners, various spinner bulkheads, prop = bolts=20 that were now too short and other various things that went=20 wrong  during the effort to make this work right?

Tracy

 

As always the difference is in the attention to = details=20 that affect the operation.  Sound like you have the right = combination of=20 prop and gearbox ratio to overcome those limitations.   I = wonder if=20 a 3 bladed prop might not be the answer for those prop length=20 challenged.  

 You mentioned seeing 7050 rpm - if at = 1000 MSL=20 and 75F OAT if you were running WOT and rich, that appears to give you = right=20 at 200HP out of your engine.  I don't suppose you noticed your = fuel burn=20 rate?  I would think it would be around 18 GPH. My calculations = indicate=20 around 18.5 gph.

Ed = Anderson

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