X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 09 Oct 2009 16:25:45 -0400 Message-ID: X-Original-Return-Path: Received: from sfa.gami.com ([68.89.254.162] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3880425 for lml@lancaironline.net; Fri, 09 Oct 2009 12:16:46 -0400 Received-SPF: none receiver=logan.com; client-ip=68.89.254.162; envelope-from=gwbraly@gami.com Received: from localhost (localhost.localdomain [127.0.0.1]) by sfa.gami.com (Postfix) with ESMTP id 5FBA18EB for ; Fri, 9 Oct 2009 11:16:10 -0500 (CDT) Received: from gamimail1.Gami.local (mail.gami.com [10.10.10.33]) by sfa.gami.com (Postfix) with ESMTP id A2D02866 for ; Fri, 9 Oct 2009 11:16:08 -0500 (CDT) Received: from gamimail1.Gami.local ([10.10.12.14]) by gamimail1.Gami.local ([10.10.12.14]) with mapi; Fri, 9 Oct 2009 11:15:55 -0500 From: George Braly X-Original-To: Lancair Mailing List X-Original-Date: Fri, 9 Oct 2009 11:15:52 -0500 Subject: RE: [LML] Re: LOP MP setting for TSIO-550E Thread-Topic: [LML] Re: LOP MP setting for TSIO-550E Thread-Index: AcpI6gUyIX30BENKSImrzxkuExb1KQAEQ57w X-Original-Message-ID: References: In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: multipart/alternative; boundary="_000_C273A1B35F3C6748B52EE0CC2FCEE96C013D23F7EA10gamimail1Ga_" MIME-Version: 1.0 X-Virus-Scanned: by amavisd-new-2.3.2 (20050629) (Debian) at gami.com --_000_C273A1B35F3C6748B52EE0CC2FCEE96C013D23F7EA10gamimail1Ga_ Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Paul, >> I think the flaw in that argument is the GPH per HP for a specific regim= e (ROP versus LOP) as your specific fuel consumption will change depending = on that setting. Your HP should be directly proportional to RPM and MP at = any mixture. I think I'm correct in that last statement regardless of wheth= er the engine is ROP or LOP.<< That has been a nearly universal understanding by pilots for decades. But = it turns out not to be accurate. TRUE when ROP. Not true when LOP. ROP - - horsepower is controlled by mass air flow through the engine. The = MAF is primarily a function of MP, RPM, and induction air temperature. Th= ere are second order effects. LOP - - horsepower is controlled by fuel flow. [ VERY much like a pu= re turbine engine (which always is "LEAN of PEAK" ) . The "throttle" is r= eally just a fuel flow lever.] If you are ROP and you add 1 gph, you get almost no change in HP. LOP - - if you add 1 gph in fuel flow you get about 14 to 15 additional H= p, depending on the engine configuration. Regards, George PS. We teach a class that covers all of this - - www.advancedpilot.com From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of paul= miller Sent: Friday, October 09, 2009 9:09 AM To: lml@lancaironline.net Subject: [LML] Re: LOP MP setting for TSIO-550E I think the flaw in that argument is the GPH per HP for a specific regime (= ROP versus LOP) as your specific fuel consumption will change depending on = that setting. Your HP should be directly proportional to RPM and MP at any= mixture. I think I'm correct in that last statement regardless of whether = the engine is ROP or LOP. When I ran the TSIO-520NB with GAMI the procedur= e would be to bump up the MP to keep the desired HP (65%, 70% or whatever y= ou choose). You have to bring the MP back up as the fuel flow drops off. = So, I would pick your desired power setting for LOP ops (say 65% for tal= king purposes) and get the MP and RPM for that power setting. When you go= LOP work towards bringing the MP back up to maintain your target power. T= hat is what I recall for the GAMIs so I would be interested if that might b= e what was being taught more recently. As I said in an earlier posting, th= e only problem with high altitude turbo ops LOP was the need to bump up the= MP to keep the wastegate from bootstrapping. Others may need higher MP fo= r pressurization but I never experienced that in the twin. Hope that all m= akes sense. Paul Miller Calgary (Legacy) On 2009-10-08, at 6:13 PM, Isaac Heizer wrote: My ES-P has a TSIO-550E with GAMI injectors, and i've recently been through= advancedpilot's web LOP course. But I'm still unclear on at least one poi= nt. My TSIO-550E will happily run at 17.5 GPH at a MP of any of 30, 31, 32 (amo= ng others). All cylinders remain below 380, and TIT is reasonable. My understanding is multiplying 14.7 x GPH yields HP, in this case 73.5% po= wer Is it 73% power no matter how I set the MP, so long as temperatures remain = in control? If that's true, why would I select one MP over another (realiz= ing I can't run wide open throttle)? --_000_C273A1B35F3C6748B52EE0CC2FCEE96C013D23F7EA10gamimail1Ga_ Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Paul,

 

>> I think the flaw in that argument is the GPH= per HP for a specific regime (ROP versus LOP) as your specific fuel consumption will change depending on that setting.  Your HP should be directly proportional to RPM and MP at any mixture. I think I'm correct in that last statement regardless of whether the engine is ROP or LOP.<<

 

That has been a nearly universal understanding by pilo= ts for decades.  But it turns out not to be accurate.

 

TRUE when ROP.

 

Not true when LOP.

 

ROP - - horsepower is controlled by mass air flow thro= ugh the engine.  The MAF is primarily a function of  MP, RPM, and induction air temperature.  There are second order effects.=

 

LOP  - -  horsepower is controlled by  = fuel flow.     [ VERY much like a pure turbine engine (which always is “LEAN of PEAK” ) .   The “throttle= 221; is really just a fuel flow lever.]

 

If you are  ROP and you add 1 gph,  you get almost= no change in HP.

 

LOP - - if you add 1 gph in fuel flow you get about  14= to 15  additional Hp, depending on the engine configuration.

 

Regards,  George

 

PS.  We teach a class that covers all of this - - = www.advancedpilot.com<= /span>

 

 

 

 

 

From: Lancair Maili= ng List [mailto:lml@lancaironline.net] On Behalf Of paul miller
Sent: Friday, October 09, 2009 9:09 AM
To: lml@lancaironline.net
Subject: [LML] Re: LOP MP setting for TSIO-550E

 

I think the flaw in that argument is the GPH per HP fo= r a specific regime (ROP versus LOP) as your specific fuel consumption will cha= nge depending on that setting.  Your HP should be directly proportional to= RPM and MP at any mixture. I think I'm correct in that last statement regardles= s of whether the engine is ROP or LOP.  When I ran the TSIO-520NB with GAMI= the procedure would be to bump up the MP to keep the desired HP (65%, 70% or whatever you choose).   You have to bring the MP back up as the fuel f= low drops off.    So, I would pick your desired power setting for LOP= ops (say 65% for talking purposes) and get the MP and RPM for that power settin= g.   When you go LOP work towards bringing the MP back up to maintain you= r target power.  That is what I recall for the GAMIs so I would be interested if that might be what was being taught more recently.  As I said in an earlier posting, the only problem with high altitude turbo ops L= OP was the need to bump up the MP to keep the wastegate from bootstrapping. &n= bsp;Others may need higher MP for pressurization but I never experienced that in the t= win.  Hope that all makes sense.  

 

Paul Miller

Calgary (Legacy) 

On 2009-10-08, at 6:13 PM, Isaac Heizer wrote:



My ES-P has a TSIO-550E with GAMI injectors, and i've recently been through advancedpilot's web LOP course.  But I'm still unclear on at least one point.

My TSIO-550E will happily run at 17.5 GPH at a MP of any of 30, 31, 32 (amo= ng others).  All cylinders remain below 380, and TIT is reasonable.

My understanding is multiplying 14.7 x GPH yields HP, in this case 73.5% po= wer

Is it 73% power no matter how I set the MP, so long as temperatures remain = in control?  If that's true, why would I select one MP over another (realizing I can't run wide open throttle)?

 

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