X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 21 Aug 2011 14:09:47 -0400 Message-ID: X-Original-Return-Path: Received: from smtp124.dfw.emailsrvr.com ([67.192.241.124] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTPS id 5097862 for lml@lancaironline.net; Fri, 19 Aug 2011 17:43:00 -0400 Received-SPF: none receiver=logan.com; client-ip=67.192.241.124; envelope-from=walter@advancedpilot.com Received: from localhost (localhost.localdomain [127.0.0.1]) by smtp2.relay.dfw1a.emailsrvr.com (SMTP Server) with ESMTP id 3FA3A78118 for ; Fri, 19 Aug 2011 17:42:26 -0400 (EDT) X-Virus-Scanned: OK Received: by smtp2.relay.dfw1a.emailsrvr.com (Authenticated sender: walter-AT-advancedpilot.com) with ESMTPSA id EE45078094 for ; Fri, 19 Aug 2011 17:42:25 -0400 (EDT) From: Walter Atkinson Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: multipart/alternative; boundary=Apple-Mail-4-475495949 Subject: Re: [LML] lean of peak ? X-Original-Date: Fri, 19 Aug 2011 15:42:24 -0600 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: X-Mailer: Apple Mail (2.1084) --Apple-Mail-4-475495949 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 Bill: Several issues of fact should be discussed: ** [ green amber red blue ] do you remember those colors well the lead = helped lub the engine as well .I think the heat is destroying these = engines through several issues** Heat is a bad thing. The hottest possible mixture is 40dF ROP. = Anything else is cooler. ** Lean of peak, poor induction air cooling and no lead additive** Lead is in the fuel to improve detonation margin. It has no other = function. It is NOT a lubricant in any manner. Bromide is placed in = the fuel to act as a scavenger of the lead to get it out of the = induction chamber. Lead exists during the combustion event as a salt of = bromide--lead-oxy-bromide. It becomes a vapor at 1305dF so with a = combustion temperature of 3800dF or so, it doesn't hang around. If it = did, it is a salt. Salts are abrasive. Abrasives make very poor = lubricants. **I really think the best way to tell if you are going to far into lean = of peak is look at all the blue parts that are in the engine at break = down ** That would imply that running LOP generates heat. The converse is true. = LOP operation at the same HP as ROP operation WILL be generating LESS = heat. **Everyone seems to want the lean of peak and I don=92t understand that = other than the fuel cost. I guess do what you think is best fuel cost or = engine brake down at half tbo the real question is are you making the = tbo and I have heard of only a few that can say they are These = engines were certified back when fuel was leaded and the numbers = represent cert not 100ll My best guess on total times is 2500 hrs in c 206/ c 210 and 7500 hrs = in other cessna 150 through 421 all this time was in the late 60=92s = and 70=92s My thoughts are only mine so when you brake down at less than 500 hr = maybe you are running to lean also maybe we should get a chart of = actually who is running lean of peak with gami and cert and the actual = hrs it ran before brake down on the whole fleet Bill Maddox** Bill, there are over 400 MILLION flight hours of data on this subject in = big radials and over 5 MILLION flight hours of LOP operation in today's = flat engines. The LOP run engines run cooler, the oil stays cleaner = longer and the engines operate under less pressure stress. Heat and = pressure are the enemies of metal. LOP ops have the advantage of both. = Again, 40dF ROP is the mixture that will guarantee the highest heat and = pressure in the engine. If this interests you and you would like to kill about 20 or so Old = Wives Tales concerning engine management, join us in Ada October 7-9. Walter Atkinson Advanced Pilot Seminars= --Apple-Mail-4-475495949 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 Bill:

Several issues of fact = should be discussed:

** [ green amber red blue ] do you remember those = colors well the lead helped lub the engine as well .I think the heat is = destroying these engines through several = issues**
Heat is a bad thing. =  The hottest possible mixture is 40dF ROP.  Anything else is = cooler.
** Lean of peak, poor = induction air cooling and no lead  = additive**
Lead is in the fuel to = improve detonation margin.  It has no other function.  It is = NOT a lubricant in any manner.  Bromide is placed in the fuel to = act as a scavenger of the lead to get it out of the induction chamber. =  Lead exists during the combustion event as a salt of = bromide--lead-oxy-bromide.  It becomes a vapor at 1305dF so with a = combustion temperature of 3800dF or so, it doesn't hang around. If it = did, it is a salt.  Salts are abrasive.  Abrasives make very = poor lubricants.
**I really think the = best way to tell if you are going to far into lean of peak is look at = all the blue parts that are in the engine at break down = **
That would imply that = running LOP generates heat.  The converse is true.  LOP = operation at the same HP as ROP operation WILL be generating LESS = heat.
**Everyone seems to want = the lean of peak and I don=92t understand that other than the fuel cost. = I guess do what you think is best fuel cost or engine brake down at half = tbo  the real question is are you making the tbo and  I have = heard of only a few that can say they are   These engines were = certified  back when fuel was leaded and the numbers represent cert = not 100ll
 My thoughts are only mine so when you = brake down at less than 500 hr maybe you are running to lean also maybe = we should get a chart of actually who is running lean of peak with gami = and cert and the actual hrs it ran before brake down on the whole fleet = Bill  Maddox**

Bill, there are over 400 MILLION flight = hours of data on this subject in big radials and over 5 MILLION flight = hours of LOP operation in today's flat engines.  The LOP run = engines run cooler, the oil stays cleaner longer and the engines operate = under less pressure stress.  Heat and pressure are the enemies of = metal. LOP ops have the advantage of both.  Again, 40dF ROP is the = mixture that will guarantee the highest heat and pressure in the = engine.

If = this interests you and you would like to kill about 20 or so Old Wives = Tales concerning engine management, join us in Ada October = 7-9.

Walter Atkinson
Advanced Pilot = Seminars
= --Apple-Mail-4-475495949--