X-Virus-Scanned: clean according to Sophos on Logan.com From: "Mark Steitle" Received: from mail-oi0-f50.google.com ([209.85.218.50] verified) by logan.com (CommuniGate Pro SMTP 6.1.2) with ESMTPS id 7739462 for flyrotary@lancaironline.net; Mon, 08 Jun 2015 06:34:22 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.218.50; envelope-from=msdstx@gmail.com Received: by oiha141 with SMTP id a141so26256055oih.0 for ; Mon, 08 Jun 2015 03:33:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=subject:references:from:content-type:in-reply-to:message-id:date:to :content-transfer-encoding:mime-version; bh=iVSSvXVKOBcDwzeEsGsiwfScTSq8E/qvwlv41e6CQXU=; b=Bop91wRH4XS5xq1qXIzkwcm+d9w1LiaEDtVaozPeXqUc/i44EwY8W5bf7svTSxAhsk xzhMKG2fkQ8ClaGr/tZ/YmqOgwp+x3Czd7Z1y9CIYDreouBpFNtBraXRxwOBwX45Z2j1 OdS0svIdVc8pMYCyQ8UMulVd5+ZefO/CT7qD0EUXwtaZGzq9Vp+8nXciyKwNCFQbV1tP jeoEtcT409Op7YtCe/LYihBcC1WV/2NGoW09h0TNq7J/i/u1rDLqUiy59CbP7c9wItfV 1tSENZ3rSrgXydCh8C68k/fYd5ci43+nWVp6XViMcY070o9LK+L4GSn+s7t7+NaXihdE NmjA== X-Received: by 10.60.125.169 with SMTP id mr9mr13631657oeb.14.1433759626711; Mon, 08 Jun 2015 03:33:46 -0700 (PDT) Return-Path: Received: from [192.168.1.128] (104-7-222-198.lightspeed.austtx.sbcglobal.net. [104.7.222.198]) by mx.google.com with ESMTPSA id m19sm1518228oik.5.2015.06.08.03.33.44 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 08 Jun 2015 03:33:45 -0700 (PDT) Subject: Re: [FlyRotary] Re: new operating question References: Content-Type: multipart/alternative; boundary=Apple-Mail-3120B7A9-7D77-431E-BB92-7053382D01DA X-Mailer: iPad Mail (12F69) In-Reply-To: Message-Id: <19A65303-C365-48BE-99BE-D9214345E04B@gmail.com> Date: Mon, 8 Jun 2015 05:33:43 -0500 To: Rotary motors in aircraft Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (1.0) --Apple-Mail-3120B7A9-7D77-431E-BB92-7053382D01DA Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Bill, That sounds a bit optimistic based on my fuel burn. Tracy has a SWAG that s= ays you'll produce 100 hp for every 10 gph. At cruise I'm burning about 11.= 5 - 12.5 gph, so I figure I'm producing around 110- 125 hp at 5100 -5200 rpm= . This results in an IAS of 200 - 210 mph, depending on CG. This is compara= ble to the IO-540 Lancair ES.=20 By comparison, the Lancair Columbia 300, which is based on the same airframe= as the Lancair ES, with an IO-550-N2B (6 cyl, 1 turbo, 3-blade c/s prop) cr= uising at 75% power, shows at 191 kts at 18,000 MSL. The IO-550-N is rated a= t 310 hp at 2700 rpm. If you believe Continental's numbers, 75% of 310 is 2= 32 hp, which is closer to your numbers than to mine.=20 =46rom a different approach, if I'm burning 12 gph, at .57 BSFC, that works o= ut to 126 hp, much closer to what we get using Tracy's SWAG method. One oth= er thing, the Columbia numbers are at 18000 MSL while mine are at 6500 MSL. = =20 Mark Sent from my iPad > On Jun 7, 2015, at 5:37 PM, Bill Bradburry w= rote: >=20 > Mark, > =20 > Here is a dyno chart where a semi p-port (I don=E2=80=99t know what that m= eans) 20B is making about 190 hp at 5100 rpm. Do you think that is about wh= at your engine is doing based on your plane=E2=80=99s performance vs ESs wit= h IO-550s in them? > =20 > Bill > From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]=20 > Sent: Sunday, June 07, 2015 5:13 PM > To: Rotary motors in aircraft > Subject: [FlyRotary] Re: new operating question > =20 > Rich, > I've been running a constant speed M/T on my. 3-rotor for years now. I typ= ically adjust prop rpm for a max of 7k rpm for takeoff, WOT. Once a climb h= as been established I bring the rpm down to around 6k for the remainder of c= limb. For cruise, I leave throttle set to WOT, but set rpm via prop setting t= o give 5100 rpm. For sightseeing flights, I'll back off the throttle to giv= e around 150 kts.=20 > =20 > Mark >=20 > Sent from my iPad >=20 >> On Jun 7, 2015, at 9:33 AM, ARGOLDMAN wrote= : >> Greetings genlepeople of the rotary pursuasion, >> =20 >> For those of you using variable pitch (C/S) props, an operating question t= hat has been bugging me. Perhaps the collective wisdom of this group can set= my mind at rest. >> =20 >> In piston aircraft engines, the concept of running over squared MP vs RP= M has been heavily questioned to the extent that some suggest running at ful= l throttle all the time and controlling the power output via RPM (within rea= son). The thought is to, I believe, eliminate the induction restriction of t= he butterfly valve increasing the efficiency. >> =20 >> Now we have a rotor spinning, a gear box gearing and a propeller propelli= ng. Does this concept hold true for the rotaries. What are people doing in t= erms of setting power after take off (full throttle max RPM). >> =20 >> My enquiring and rotating mind wants to know.=20 >> =20 >> (Unturbocharged Renesis with RD1-c Box) >> =20 >> Thanks >> =20 >> Rich --Apple-Mail-3120B7A9-7D77-431E-BB92-7053382D01DA Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable
Bill,
That sounds a bit opti= mistic based on my fuel burn.  Tracy has a SWAG that says you'll produc= e 100 hp for every 10 gph.  At cruise I'm burning about 11.5 - 12.5 gph= , so I figure I'm producing around 110- 125 hp at 5100 -5200 rpm.  This= results in an IAS of 200 - 210 mph, depending on CG. This is comparable to t= he IO-540 Lancair ES. 

By comparison, the Lanc= air Columbia 300, which is based on the same airframe as the Lancair ES, wit= h an IO-550-N2B (6 cyl, 1 turbo, 3-blade c/s prop) cruising at 75% power, sh= ows at 191 kts at 18,000 MSL.  The IO-550-N is rated at 310 hp at 2700 r= pm.  If you believe Continental's numbers, 75% of 310 is 232 hp, which i= s closer to your numbers than to mine. 

=46rom= a different approach, if I'm burning 12 gph, at .57 BSFC, that works out to= 126 hp, much closer to what we get using Tracy's SWAG method.  One oth= er thing, the Columbia numbers are at 18000 MSL while mine are at 6500 MSL. &= nbsp;

Mark


Sent from my iPad

On Jun 7, 2015, at 5:37 PM, Bill Bradburry <flyrotary@lancaironline.net> wrote:
=

Mark,

 

Here is a dyno chart where a semi p-por= t (I don=E2=80=99t know what that means) 20B is making about 190 hp at 5100 rpm.&= nbsp; Do you think that is about what your engine is doing based on your plane=E2=80= =99s performance vs ESs with IO-550s in them?

 

Bill

From: Rotary motors in aircraft [mailto:flyrotary@lancaironli= ne.net]
Sent: Sunday, June 07, 2015 5= :13 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: new operating question

 

Rich,

I've been running a constant speed M/T on my. 3-rotor for years now.= I typically adjust prop rpm for a max of 7k rpm for takeoff, WOT.  Once a= climb has been established I bring the rpm down to around 6k for the remaind= er of climb. For cruise, I leave throttle set to WOT, but set rpm via prop sett= ing to give 5100 rpm.  For sightseeing flights, I'll back off the throttle t= o give around 150 kts. 

 

Mark

Sent from my iPad


On Jun 7, 2015, at 9:33 AM, ARGOLDMAN <flyrotary@lancaironline.net> wrote:

Greetings genlepeople of the rotary pursuasion,

 

For those of you using variable pitch (C/S) props, an operating question that has been bugging me. Perhaps the collective wisdom of this group can set my mind at rest.

 

In piston aircraft engines, the concep= t of running over squared  MP vs RPM has been heavily questioned to t= he extent that some suggest running at full throttle all the time and controlli= ng the power output via RPM (within reason). The thought is to, I believe, eliminate the induction restriction of the butterfly valve increasing the ef= ficiency.

 

Now we have a rotor spinning, a gear b= ox gearing and a propeller propelling. Does this concept hold true for the rotaries. What are people doing in terms of setting power after take off (fu= ll throttle max RPM).

 

My enquiring and rotating mind wants t= o know. 

 

(Unturbocharged Renesis with RD1-c Box= )

 

Thanks

 

Rich

= --Apple-Mail-3120B7A9-7D77-431E-BB92-7053382D01DA--