X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-bw0-f217.google.com ([209.85.218.217] verified) by logan.com (CommuniGate Pro SMTP 5.3.3) with ESMTP id 4155360 for flyrotary@lancaironline.net; Sun, 07 Mar 2010 10:48:29 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.218.217; envelope-from=lehanover@gmail.com Received: by bwz9 with SMTP id 9so204229bwz.5 for ; Sun, 07 Mar 2010 07:47:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:date:message-id:subject :from:to:content-type; bh=avLBf0lgbTdGuCWvlF/Auf/zlew/gl1vTXZUFIC6RHo=; b=Eqz/GepZGCt17yc7g514pqwK3JtXGEofxhVArclDUHV4VlGy7qlgfKM0qhZjuOXlZZ pdmQcGb1FB5DxiwzBom0thpXqtNzKKrGD9DOUv/Ep5eqkOhyb1m8xebZfYy6BSR/p/in Z3i8LmNZhfsn1iWG1qVpchRmQaB6HyQIbRTig= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=xk+Z1URMF2VTSf/VokfyrPUClVkF/CsZK/ZvtR0gQH3dYSMjrMG9h0r5av5IV1X1IM bQVnYa6ieQYRftI3HHKGJud57ATcoagbfICm3hYb32exEFjPNcNvVAsL5/yS4zqctQxm zepdKbjcl+HC2I21qd/Kj89Xiba7e1JApFmfM= MIME-Version: 1.0 Received: by 10.204.4.150 with SMTP id 22mr3432084bkr.192.1267976871307; Sun, 07 Mar 2010 07:47:51 -0800 (PST) Date: Sun, 7 Mar 2010 10:47:51 -0500 Message-ID: <1ab24f411003070747i49f5156fk828ec988d3ead3c9@mail.gmail.com> Subject: Paul Lipps propellers From: Lynn Hanover To: flyrotary@lancaironline.net Content-Type: multipart/alternative; boundary=001517588886ff6c89048137de31 --001517588886ff6c89048137de31 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable *Here is a picture of that same Biplane showing an alarming use of the same idea to build a whole wing. The cowl has enough good stuff going on, to keep me busy for months.* ** *http://www.biplaneracing.com/* ** *When the windscreen is far enough back then the cowl top remains a low pressure area and * *cooling airflow out of top vents is much improved, so intake holes can be even smaller. * *Plus after flight cooling is quick and in cowl baking is reduced. * ** *Not seen is that the lower wing is a Gull wing plan form for short stiff/light gear, and greater distance between wings for less interplane interference, so, the smaller lighter wings and small wing area work better= . The stager makes for less CG sensitivity , so a lower tail area works, and the tiny fuselage cross section makes for lower wetted area. * ** *The prop tips on Paul Lipps little plane are protected with tennis balls t= o protect the blades from damage, and passersby from injury. The tips are as if kitchen butcher knives. * ** *I got to hear one of his lectures at Gene NV. At the Contact magazine alternative engine roundup. I am afraid that he has forgotten more about props than I will ever learn.* ** *Lynn E. Hanover* ** I believe you are correct, Lynn There were a couple of fairly recent developments that I thought held some promises in prop design, but they do not appear to have panned out. One was the =93bi cambered=94 prop blade which as best I recall was suppose= to provide more thrust =96 I believe it did lower the Prop noise somewhat, but the increased thrust does not seem to have developed. The vortex generators (of one type or another) on the prop blades =96 the o= ne most commonly seen were the dimpled or holey tape. Again have not seen tha= t recently Then the one that looked to have the most promises was the Lipps prop blad= e =96 narrow near the hub and tip and broad near the mid section. I really s= eem to prove itself in racing =96 but have not hear of it bring that apparent promise of improved performance to the common crowd. http://www.biplaneracing.com/files/Issue77_8-13.pdf That about all I can recall recently Ed Ed Anderson --001517588886ff6c89048137de31 Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable
Here is a picture of that same Biplane showing an alarming use of = the same idea to build=A0 a whole wing. The cowl has enough good stuff goin= g on, to keep me busy for months.
=A0
http://www.biplaneracing= .com/=A0
=A0
When the windscreen is far enough back then the cowl top remains a= low pressure area and
cooling airflow out of top vents is much improved, so intake holes= can be even smaller.
Plus after flight cooling is quick and in cowl baking is reduced. =
=A0
Not seen is that the lower wing is a Gull wing plan form for short= stiff/light gear, and greater distance between wings for less interplane i= nterference, so, the smaller lighter wings and small wing area work better.= The stager makes for less CG sensitivity , so a lower tail area works, and= the tiny fuselage cross section makes for lower wetted area.
=A0
The prop tips on Paul Lipps little plane are protected with tennis= balls to protect the blades from damage, and passersby from injury. The ti= ps are as if kitchen butcher knives. =A0
=A0
I got to hear one of his lectures at Gene NV. At the Contact magaz= ine alternative engine roundup. I am afraid that he has forgotten more abou= t props than I will ever learn.
=A0
Lynn E. Hanover
=A0

I bel= ieve you are correct, Lynn

<= /p>

There were a co= uple of fairly recent developments that I thought held some promises in pro= p design, but they do not appear to have panned out.

<= /p>

One was the =93= bi cambered=94 prop blade which as best I recall was suppose to provide mor= e thrust =96 I believe it did lower the Prop noise somewhat, but the increa= sed thrust does not seem to have developed.

<= /p>

The vortex gene= rators (of one type or another) on the prop blades =96 the one most commonl= y seen were the dimpled or holey tape.=A0 Again have not seen that recently=

=A0Then the one that looked to have the= most promises was the Lipps prop blade =96 narrow near the hub and tip and= broad near the mid section.=A0 I really seem to prove itself in racing =96= but have not hear of it bring that apparent promise of improved performanc= e to the common crowd.

=A0

=A0

3D""http://www.biplaneracing.com/fil= es/Issue77_8-13.pdf

=A0

That about all = I can recall recently

=A0

Ed

=A0

Ed Anderson

--001517588886ff6c89048137de31--