X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-gx0-f180.google.com ([209.85.161.180] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTPS id 5080983 for flyrotary@lancaironline.net; Wed, 03 Aug 2011 16:00:43 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.161.180; envelope-from=editor.contactmagazine@gmail.com Received: by gxk10 with SMTP id 10so1268223gxk.25 for ; Wed, 03 Aug 2011 13:00:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:reply-to:in-reply-to:references:date:message-id :subject:from:to:content-type; bh=r3qJ1AzGwXb4G8L1IFIAemZVwYaCblPwhutkk+LYMqM=; b=xZiZy7coA4cCTZrjupwDqK2shyFqwNbgX0SrPruEF9u/qYnMnbg6Vs8EWZR2OBSVon NIsdRNgJjID1ZFea4TURSTNRGdUi81O34hijpfsIiLrL9Lo7j252Xv0yuKuUPXkGZ3VR RJdqp1M3JKFcOjHEXGW3x9FT/s+YeEy9zNQPU= MIME-Version: 1.0 Received: by 10.236.170.4 with SMTP id o4mr1320299yhl.340.1312401606027; Wed, 03 Aug 2011 13:00:06 -0700 (PDT) Received: by 10.236.207.5 with HTTP; Wed, 3 Aug 2011 13:00:05 -0700 (PDT) Reply-To: panzera@experimental-aviation.com In-Reply-To: References: Date: Wed, 3 Aug 2011 13:00:05 -0700 Message-ID: Subject: Re: [FlyRotary] Re: Ross Farnham IVO testing From: Pat Panzera To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=20cf3040e90c87a80f04a99f4f0b --20cf3040e90c87a80f04a99f4f0b Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Every part of ever aircraft can do one or more of the following. It can add weight It can add drag It can add lift. Thrust is a form of lift, especially when produced by a propeller. Drag can be on the airframe or the engine, and is a bad thing. Weight ultimately causes drag. So... if you have to carry around the extra weight of the first 16 inches o= f a 72" prop, why would you want to cover it up? Why not have at least half o= f that 16 inches produce forward thrust? ...or at a minimum, help cool the engine? The large spinner is at best a band-aid, that will cause aerodynamic drag i= n order to shield the aerodynamic drag from a honorably designed propeller, that causes drag on the engine (shielded or not) and additional weight on the aircraft. I suppose that if you MUST use the IVOPROP, then this is an effective way t= o minimize the negative effects of using the prop, but by far, the tradeoff just isn't worth it. The allure of in-flight adjustability is understandable, but in reality, it's difficult to beat a properly designed fixed-pitch prop. On Tue, Aug 2, 2011 at 8:51 PM, Kelly Troyer wrote: > Doug, Pat and All, > > When Tracy tested the "IVO" against his "Performance Prop" he > gained a lot in takeoff and climb > performance but lost considerable top speed and coolant temp went > up.............He attributed both the > speed loss and higher coolant temps to the flat hub area of the "IVO" > blades which his spinner did not > cover (added drag) and essentially blocked some coolant air from his > radiators................This flat area > also as has been noted sucks up hp but produces no thrust.............. > > I have a three blade 74 inch electric in-flight adjust "IVO" > prop for my "Dyke Delta" that if I live long > enough to get in the air will have a 16 inch diameter "Mustang 2" spinne= r > which will cover most of this > flat area of the "IVO" blade hub.............The "IVO" seems to work well > in the pushers from all reports > since the flat blade hubs are mostly shielded by the engine cowl in these > installations............IMHO > > Kelly Troyer > *"DYKE DELTA JD2" (Eventually)* > "13B ROTARY"_ Engine > "RWS"_RD1C/EC2/EM2 > "MISTRAL"_Backplate/Oil Manifold > "TURBONETICS"_TO4E50 Turbo > > *From:* Pat Panzera > *To:* Rotary motors in aircraft > *Sent:* Tuesday, August 2, 2011 8:48 PM > *Subject:* [FlyRotary] Re: Ross Farnham IVO testing > > Jim Smith with his 150 HP, auto-fuel RV-6 is reaching speeds of 200 mph > TAS using a fixed-pitch, three-blade wood Elippse propeller. > > That's nearly 30 mph more than the Ivo, on the same? power. > > > On Tue, Aug 2, 2011 at 6:18 PM, wrote: > > http://www.sdsefi.com/rv13.htm > > Ross did quite a bit of prop testing in turbo subie powered RV-6. I've > e-mailed him a few times regarding performance, mx issues, etc. and he > still thinks it's a good way to go as long as the Magnum hi pitch blades = are > used (at least for a/c w/RV type performance). > Sent on the Sprint=AE Now Network from my BlackBerry=AE > -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: > http://mail.lancaironline.net:81/lists/flyrotary/List.html > > > > > --20cf3040e90c87a80f04a99f4f0b Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Every part of ever aircraft can do one or more of the following.
It can= add weight
It can add drag
It can add lift.
=
Thrust is a form of lift, especially when produced by a prop= eller.=A0
Drag can be on the=A0airframe=A0or the engine, and is a bad thing.
Weight ultimately causes drag.

So... if you= have to carry around the extra weight of the first 16 inches of a 72"= prop, why would you want to cover it up? Why not have at least half of tha= t 16 inches produce forward thrust? ...or at a minimum, help cool the engin= e?

The large spinner is at best a band-aid, that will caus= e aerodynamic drag in order to=A0shield=A0the aerodynamic drag from a=A0hon= orably=A0designed=A0propeller, that causes drag on the engine (shielded=A0o= r not) and additional weight on the aircraft.

I suppose that if you MUST use the IVOPROP, then this i= s an effective way to minimize the negative effects of using the prop, but = by far, the tradeoff just isn't worth it.

The=A0allure=A0of in-flight=A0adjustability is understandable, but in reali= ty, it's difficult to beat a properly designed fixed-pitch prop.
<= div>

On Tue, Aug 2,= 2011 at 8:51 PM, Kelly Troyer <keltro@att.net> wrote:
Doug, Pat and All,
=A0
=A0=A0=A0=A0=A0=A0 When Tracy tested the "IVO" against his "Performance Prop" he= gained a lot in takeoff and climb
performance but lost considerable top speed and coolant temp wen= t up.............He attributed=A0both the<= /div>
speed loss and higher coolant temps to= the flat hub area of the "IVO&= quot; blades which his spinner did not
cover (added drag) and essentially blocked some coolant air from= his radiators................This flat area
also as has been noted sucks up hp but produces no thrust.......= .......
=A0
=A0=A0=A0=A0=A0 I have a three blade 74 inch electric in-flight adjust "IVO<= /span>" prop=A0for my "Dyke Delta"= =A0that if I live long
enough to get in the air will have a 16 inch diameter=A0 "M= ustang 2" spinner which will cover most of this
flat area of the "IVO" blade= hub.............The "IVO" seems to wor= k well in the pushers from all reports
since the flat blade hubs are=A0mostly=A0shiel= ded by the engine cowl in these installations.........= ...IMHO=A0
=A0
Kelly Troyer
"DYKE DELTA JD2" (Eventually)=
"13B ROTARY"_ Engine
"RWS"_RD1C/EC2/EM2
"MISTRAL"_Ba= ckplate/Oil Manifold
"TURBONETICS"_TO4E50 = Turbo

From: Pat = Panzera <editor.contactmagazine@gmail.com><= br> To: Rotary motors in aircraf= t <flyr= otary@lancaironline.net>
Sent= : Tuesday, August 2, 2011 8:48 PM
Subject: [FlyRotary] Re: Ros= s Farnham IVO testing

Jim Smith with his 150 HP, auto-fuel RV-6 i= s reaching speeds of 200 mph TAS usi= ng a fixed-pitch, three-blade wood Elippse<= /span> propeller.=20

That's nearly 30 mph more than the = Ivo, on the same? power.=A0


On Tue, Aug 2, 2011 at 6:18 PM, <dlomheim@aol.com= > wrote:
http://www.sdsefi.com/rv13.htm

Ross did quite= a bit of prop testing in turbo subie powered RV-6. =A0I've e-mailed him a few times regarding performance,= mx issues, etc. and he still thinks= it's a good way to go as long as the Magnum hi pitch blades are used (= at least for a/c w/RV type performance).
Sent on the Sprint=AE Now Network from my BlackBerry=AE
--
Homepage: =A0http://ww= w.flyrotary.com/
Archive and UnSub: =A0 http://mail.lancaironline.net:81/lists/flyrotary/List.html




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