X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 25 Oct 2013 07:48:17 -0400 Message-ID: X-Original-Return-Path: Received: from mail-oa0-f44.google.com ([209.85.219.44] verified) by logan.com (CommuniGate Pro SMTP 6.0.7) with ESMTPS id 6563678 for lml@lancaironline.net; Thu, 24 Oct 2013 18:34:57 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.219.44; envelope-from=ronlaughlin@gmail.com Received: by mail-oa0-f44.google.com with SMTP id l20so188231oag.17 for ; Thu, 24 Oct 2013 15:34:24 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.60.160.164 with SMTP id xl4mr367911oeb.69.1382654064463; Thu, 24 Oct 2013 15:34:24 -0700 (PDT) Received: by 10.182.44.101 with HTTP; Thu, 24 Oct 2013 15:34:24 -0700 (PDT) Reply-To: ronlaughlin@hotmail.com In-Reply-To: References: X-Original-Date: Thu, 24 Oct 2013 17:34:24 -0500 X-Original-Message-ID: Subject: Re: [LML] Leaning the IO 500 From: Ron Laughlin X-Original-To: Lancair Mailing List Content-Type: multipart/alternative; boundary=089e01176ac75c1bed04e9843c2b --089e01176ac75c1bed04e9843c2b Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable George, Understandably, those are very similar TAS numbers that I see with my IO-500 Cirrus. APS taught me that 50 degrees ROP is the very worst (most harmful) power setting. It certainly does produce more power than 50 degrees LOP but at the expense of maximum engine stress (internal cylinder pressure). Coincidently, it's also the power setting that is most likely to lead to pre-ignition and detonation. I don't have the APS PP presentation material you asked for (I presume it would be copyrighted anyway) but I do have a chart called the "red fin" that was derived from APS power setting recommendations/ data. It's included on a checklist card that I put together for my SR22. You're welcome to download it and modify it to meet your needs. As long as the intersection of FF and degrees LOP are outside the "red fin" I know I'm at a safe power setting: On my IO-550 I have determined that a quick and safe "go to" FF setting for LOP operations are: 15.5 gph up to 4000 ft MSL; 14.5 gph from 4000 to 7000 msl and 13.5 gph at any altitude greater than 7000 msl. Set it and forget it until I'm leveled off in cruise and have time to fine tune it. Ron On Thu, Oct 24, 2013 at 11:47 AM, George Wehrung wrote: > Does anyone have a copy of the powerpoint presentation from the advanced > pilot seminar? I ask because I think for our plane running 50=CB=9A ROP = gives > us the best performance. 50=CB=9A LOP is the best fuel economy. > > I have been collecting data especially on my cross country trip for our I= O > 550. > > Basically at 7,000 feet I found that at 50=CB=9A LOP I was indicating 170= KTS > TAS and 150 KIAS. > > At 50=CB=9A ROP I was 179 TAS and 158 KIAS. > > My EGTs/CHTs: 291/1435 LOP & 330/1431 ROP. > > When I tried 75=CB=9A ROP I slowed a couple of knots. At 100=CB=9A was i= ncreased > fuel consumption for no gain in airspeed. > > Anyhow, I pasted some data below which was typical for the 9 leg trip > across the US last week for our ferry flight. Also note, the plane is no= t > painted, which may bear differences for our ES vs others. > > > 7000 > 2400 > 150 > 170 > 12.7 > 291 > 1435 > 50=CB=9A LOP > 7000 > 2400 > 158 > 179 > 16.6 > 330 > 1431 > 50=CB=9A ROP > 7000 > 2400 > 157 > 177 > 16.8 > 332 > 1416 > 75=CB=9A ROP > 7000 > 2400 > 157 > 177 > 17.3 > 331 > 1391 > 100=CB=9A ROP > > --089e01176ac75c1bed04e9843c2b Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
George,
=C2=A0
Understandably, th= ose are very similar TAS=C2=A0numbers that I see with my IO-500 Cirrus. APS= =C2=A0taught me=C2=A0that 50 degrees ROP is the very worst (most harmful) p= ower setting. It certainly does produce more power than 50 degrees LOP but = at the expense of maximum engine=C2=A0stress (internal cylinder pressure). = Coincidently, it's also the power setting that is most likely to lead t= o pre-ignition and detonation.
=C2=A0
I don't have the APS PP presentation material you= asked for (I presume it would be=C2=A0copyrighted anyway) but I do have a = chart called the "red fin" that was derived from APS power settin= g recommendations/ data. It's included on a checklist card that I put t= ogether for my SR22. You're welcome to download it and modify it to mee= t your needs. As long as=C2=A0the intersection of=C2=A0FF and degrees LOP a= re outside the "red fin" I know I'm at a safe power setting:<= /div>
=C2=A0
=C2=A0
On my=C2=A0IO-550 I have determined = that a=C2=A0quick and=C2=A0safe "go to"=C2=A0FF setting for LOP o= perations are:=C2=A015.5 gph up to 4000 ft MSL; 14.5 gph from 4000 to 7000 = msl and 13.5 gph at any altitude greater than 7000 msl. Set it and forget i= t until I'm leveled off in cruise and have time to fine tune it.

Ron


On Thu, Oct 24, 2013 at 11:47 AM, George= Wehrung <gw5@me.com> wrote:
Does anyone have a copy of the powerpoint presentation from the = advanced pilot seminar? =C2=A0I ask because I think for our plane running 5= 0=CB=9A ROP gives us the best performance. =C2=A050=CB=9A LOP is the best f= uel economy.

I have been collecting data especially on my cross country t= rip for our IO 550.

Basically at 7,000 feet I foun= d that at 50=CB=9A LOP I was indicating 170 KTS TAS and 150 KIAS.

At 50=CB=9A ROP I was 179 TAS and 158 KIAS. =C2=A0

My EGTs/CHTs: =C2=A0291/1435 LOP & 330/1431 ROP.
<= div>
When I tried 75=CB=9A ROP I slowed a couple of knots. = =C2=A0At 100=CB=9A was increased fuel consumption for no gain in airspeed.<= /div>

Anyhow, I pasted some data below which was typical for = the 9 leg trip across the US last week for our ferry flight. =C2=A0Also not= e, the plane is not painted, which may bear differences for our ES vs other= s.


7000
2400
150
170
12.7
291
1435
50= =CB=9A LOP
7000
2400
158
179
16.6
330
1431
50= =CB=9A ROP
7000
2400
157
177
16.8
332
1416
75= =CB=9A ROP
7000
2400
157
177
17.3
331
1391
100= =CB=9A ROP


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