X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from qw-out-2122.google.com ([74.125.92.27] verified) by logan.com (CommuniGate Pro SMTP 5.3.4) with ESMTP id 4178236 for flyrotary@lancaironline.net; Thu, 25 Mar 2010 08:29:02 -0400 Received-SPF: pass receiver=logan.com; client-ip=74.125.92.27; envelope-from=rwstracy@gmail.com Received: by qw-out-2122.google.com with SMTP id 3so1905097qwe.25 for ; Thu, 25 Mar 2010 05:28:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type; bh=m5X8821qAgu0XoEGRxnWFuo6E5d2aap5Dwcy9qw5rPA=; b=q2gK+p+6TqnGKxBVBnzlEZ9106dtcz5nLEnmGRmhCbt8Op1JI/wq1NuMLQ3FVudv3u wPNNeh1FHcS4uejqtCYPVScNk3KlsOeX8AaZG/N0vaweyJyoSEvgMG1c4JCIPO55JnHn JRXv0Tclfn2++Kx4Y3/txjEHBZWO48qk/WiUc= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=d0fXUGjOowpsSwwR8llMHuK4dSPcQOnqahLg+byShUSsclelmO5w/7nCMtfULIusnz CsMPPqVZNkIEUXnOqICIk4knJCY5XFch+wyYPE6ov6d2eAyEe/6Gj10IgPlXsGSh5sP9 UB/Xn/gVJ6bCpbZ8hngP9C6Zq2PNF0YViJzpM= MIME-Version: 1.0 Sender: rwstracy@gmail.com Received: by 10.224.71.197 with SMTP id i5mr2458666qaj.381.1269520106223; Thu, 25 Mar 2010 05:28:26 -0700 (PDT) In-Reply-To: References: Date: Thu, 25 Mar 2010 08:28:26 -0400 X-Google-Sender-Auth: ef9de4f74fd5a14b Message-ID: <1b4b137c1003250528g386c811dh35f091a037ca2011@mail.gmail.com> Subject: Re: [FlyRotary] Re: Turbo Planning From: Tracy Crook To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=00c09f88cf33f7784004829f2e21 --00c09f88cf33f7784004829f2e21 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable *"If he shaves the prop off to say, 74=94, he will get a couple hundred mor= e rpm, but will probably lose in total thrust. Diameter is a big determiner in thrust. " * Hate to drag this one out again but Diameter is a big determiner of maximum static thrust. It is not the determiner of efficiency. That is determined by mass of airflow through the prop. 2" off the prop (76 to 74") will not greatly affect this on an aircraft in the speed range of an RV. Every builder that has traded those 2" for 200 -300 engine rpm has increased both rate of climb and top speed. Obviously the thrust was more after the cut. Matching the prop to the HP curve is more important than a minor change in diameter. Tracy That isn't to say that Don should make that choice, especially since he is making other changes to increase power. On Thu, Mar 25, 2010 at 12:15 AM, Bill Bradburry wrote: > Those are the best numbers I have seen with anyone with a Renesis so > far. In fact, I have not heard of numbers that good on any 13B. Don is > getting over 200 MPH with a cruise prop and climbing at over 1400 fpm wit= h > it. The only way he is going to do better is either with an electric CS > prop and/or turbo. If he shaves the prop off to say, 74=94, he will get = a > couple hundred more rpm, but will probably lose in total thrust. Diamete= r > is a big determiner in thrust. > > > > I would like more pictures of Dons intake and exhaust! > > > > Bill B > > > ------------------------------ > > *From:* Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] *O= n > Behalf Of *Al Gietzen > *Sent:* Wednesday, March 24, 2010 3:05 AM > *To:* Rotary motors in aircraft > *Subject:* [FlyRotary] Re: Turbo Planning > > 1. When I read your stats in your first paragraph, the first thought that > > comes to mind is that there is too much prop. > > > > Ditto. > > > > Al G > --00c09f88cf33f7784004829f2e21 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable "If=20 he shaves the prop off to say, 74=94, he will get a couple hundred more rpm, but will probably lose in total thrust.=A0= =20 Diameter is a big determiner in thrust. "

Hate to drag= this one out again but Diameter is a big determiner of maximum static thru= st.=A0 It is not the determiner of efficiency.=A0 That is determined by mas= s of airflow through the prop.=A0 2" off the prop (76 to=A0 74") = will not greatly affect this on an aircraft in the speed range of an RV.=A0= Every builder that has traded those 2" for 200 -300 engine rpm has in= creased both rate of climb and top speed.=A0 Obviously the thrust was more = after the cut.=A0 Matching the prop to the HP curve is more important than = a minor change in diameter.

Tracy

That isn't to say that Don should make that choice, es= pecially since he is making other changes to increase power.

On Thu, Mar 25, 2010 at 12:15 AM, Bill Bradburry <bbradburry@bell= south.net> wrote:

Those are the best numbers I have seen with anyone w= ith a Renesis so far.=A0 In fact, I have not heard of numbers that good on any 13B.=A0 Don is getting over 200 MPH with a cruise prop and climbing at over 1400 fpm wi= th it.=A0 The only way he is going to do better is either with an electric CS prop and/or turbo.=A0 If he shaves the prop off to say, 74=94, he will get a couple hundred more rpm, but will probably lose in total thrust.=A0 D= iameter is a big determiner in thrust.=A0

=A0

I would like more pictures of Dons intake and exhaus= t!

=A0

Bill B

=A0

From: Rotary motors in aircraft [mailto:fl= yrotary@lancaironline.net] On Behalf Of Al Gietzen
Sent: Wednesday, March 24,= 2010 3:05 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: T= urbo Planning

1. When I read your stats in your first paragraph, the first thought that

comes to mind is that there is too much prop.=A0

=A0

Ditto.

=A0

Al G


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