X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from web1116.biz.mail.sk1.yahoo.com ([74.6.114.48] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with SMTP id 3902726 for flyrotary@lancaironline.net; Wed, 28 Oct 2009 11:17:11 -0400 Received-SPF: none receiver=logan.com; client-ip=74.6.114.48; envelope-from=admin@haaspowerair.com Received: (qmail 91388 invoked by uid 60001); 28 Oct 2009 15:16:36 -0000 Message-ID: <869188.88804.qm@web1116.biz.mail.sk1.yahoo.com> X-YMail-OSG: 3ChUJFMVM1m3k2zoUwXS_NkpOvB_QSBg5gzRrSHf_9q6h4siUd1Jt38RRI5adHZgy.rlHbh7Ke2fm3phI64fKgnCZIusS.11EZmOABlGXsWdhrUyBCh.J5IH5WIWtXJGa99IwgJFCy_aY8lrTIvfdA8RJB15A3e_.779ua8TcEYNbRErwgI9SQhRtPqyQHRXY6VXujLzrQt8WjFJy3BGGgmqh8.6_cuX3Tgx0eWfEyQ5dU7jmpvV3bGSoQX4_WaL_gaSwIhZrX6qKHuFZuKZhdJrGvzlTYNXiQuWcdnDbDpCGg4.Flv5XXikrx6KZqYyrWJqbF4gM.YQc36yb_JcBqZOg4jyeokhjnjd4eaWtHHNTNt.oI660lTvuQDuyrpLyg-- Received: from [75.174.166.58] by web1116.biz.mail.sk1.yahoo.com via HTTP; Wed, 28 Oct 2009 08:16:35 PDT X-Mailer: YahooMailClassic/7.0.14 YahooMailWebService/0.7.347.3 Date: Wed, 28 Oct 2009 08:16:35 -0700 (PDT) From: stephen haas Subject: Re: [FlyRotary] Re: Prop Loads To: Rotary motors in aircraft In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="0-222604363-1256742995=:88804" --0-222604363-1256742995=:88804 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Yeah, =A0I was thinking the same thing. I spent many an hour running my dyno and = a pull is a pull. Data derived from those "pulls" =3D dyno=A0runs, =A0can t= hen be translated to anything you want it to read. Now if the original post= er wanted prop loads, ie, thrust loading on the motor, gyroscopic forces et= c, then a dyno won't simulate that. It takes a plane,=A0a good weather=A0da= y and rather large testicles. --- On Wed, 10/28/09, Tracy Crook wrote: From: Tracy Crook Subject: [FlyRotary] Re: Prop Loads To: "Rotary motors in aircraft" Date: Wednesday, October 28, 2009, 8:06 AM I don't understand the problem.=A0 Why do you care what the prop load is?= =A0 A dyno is used to measure the engine torque at various rpms so a dyno r= un is typically done by setting WOT (after warmup at idle of course), start= ing with enough load to hold engine at minimum rpm of interest then gradual= ly reducing load to allow rpm to rise to maximum rpm of interest.=A0=A0 The= whole run takes only seconds if all is running well. Your dyno operator will know this (or should). You can calculate prop torque later by multiplying engine torque times redr= ige ratio. Tracy=20 On Tue, Oct 27, 2009 at 10:43 PM, Greg Ward wrote= : Hey Troops; Finally in the dyno room building the mount plate to begin testing.=A0 Trac= y says that the engine should be tested with the prop on, and this is kind = of hard in a dyno room.=A0 We are mounting the engine without the PSRU, so = that we don't tear it up in testing, and instead hooking directly to the sh= aft which is loaded by means of a water brake.=A0 We can put any load on it= that we want, problem is, how to calculate that prop load in foot-pounds, = at different settings.=A0 Talked to Craig Cato, and he is leaving for Europ= e, so doesn't have time to run the calcs, and I am just a dumb high country= nail-banger.=A0 Any thoughts? Greg Ward Lancair 20B N178RG in progress --0-222604363-1256742995=:88804 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable

Yeah,

I was thinking the same thing. I spent many an hour running my d= yno and a pull is a pull. Data derived from those "pulls" =3D dyno run= s, can then be translated to anything you want it to read. Now if the= original poster wanted prop loads, ie, thrust loading on the motor, gyrosc= opic forces etc, then a dyno won't simulate that. It takes a plane, a = good weather day and rather large testicles. <GG>

--- On = Wed, 10/28/09, Tracy Crook <tracy@rotaryaviation.com> w= rote:

From: Tracy Crook <tracy@rotaryaviation.com>= ;
Subject: [FlyRotary] Re: Prop Loads
To: "Rotary motors in aircraft"= <flyrotary@lancaironline.net>
Date: Wednesday, October 28, 2009, = 8:06 AM

I don't understand the problem. Why do you car= e what the prop load is? A dyno is used to measure the engine torque = at various rpms so a dyno run is typically done by setting WOT (after warmu= p at idle of course), starting with enough load to hold engine at minimum r= pm of interest then gradually reducing load to allow rpm to rise to maximum= rpm of interest. The whole run takes only seconds if all is ru= nning well.

Your dyno operator will know this (or should).

Yo= u can calculate prop torque later by multiplying engine torque times redrig= e ratio.

Tracy

On Tue, Oct 27, 2009 at 10:43 PM, Greg Ward <gregw@onestopdesign.biz> wrote:

Hey Troops;

Finally in the dyno room building the mount plat= e to begin testing. Tracy says that the engine should be tested with = the prop on, and this is kind of hard in a dyno room. We are mounting= the engine without the PSRU, so that we don't tear it up in testing, and i= nstead hooking directly to the shaft which is loaded by means of a water br= ake. We can put any load on it that we want, problem is, how to calcu= late that prop load in foot-pounds, at different settings. Talked to = Craig Cato, and he is leaving for Europe, so doesn't have time to run the c= alcs, and I am just a dumb high country nail-banger. Any thoughts?

Greg Ward

Lancair 20B N178RG in progress

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