X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 19 Oct 2009 14:21:10 -0400 Message-ID: X-Original-Return-Path: Received: from smtp-auth-01.mx.pitdc1.expedient.net ([206.210.66.134] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTPS id 3891189 for lml@lancaironline.net; Mon, 19 Oct 2009 14:20:52 -0400 Received-SPF: none receiver=logan.com; client-ip=206.210.66.134; envelope-from=rpastusek@htii.com Received: from HTBOB001 (unknown [65.202.210.118]) by smtp-auth-01.mx.pitdc1.expedient.net (Postfix) with ESMTPA id 925EF84084 for ; Mon, 19 Oct 2009 14:20:18 -0400 (EDT) From: "Robert Pastusek" X-Original-To: "'Lancair Mailing List'" References: In-Reply-To: Subject: RE: [LML] TIT rise X-Original-Date: Mon, 19 Oct 2009 14:20:14 -0400 X-Original-Message-ID: <068901ca50e8$cdffab40$69ff01c0$@com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_068A_01CA50C7.46EE0B40" X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AcpQvsHdlcGr7g1SRKG26l1b3oLlpgAKHRyw Content-Language: en-us This is a multi-part message in MIME format. ------=_NextPart_000_068A_01CA50C7.46EE0B40 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit My experience corresponds with Steve Richard's, and I agree with Jonathan Fuller's analysis. I run my IV-P (TSIO-550E) 100-120 lean of peak, at 2300 RPM and 27-28" MP depending on temp and altitude. I typically re-set the fuel flow 45-60 minutes after level-off and it stays very steady from that point on. Just came east to Manassas (HEF) in two hops from Inyokern (IYK), CA, stopping in Arlington, TX (GKY). This gradual increase in TITs over the first 45 minutes or so happened on both legs at FL 210/190; very steady after that.reset and no change until descent time, although the OAT cooled at least 20 more degrees on the second leg to HEF. Bob From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of Jonathan Fuller Sent: Monday, October 19, 2009 9:19 AM To: lml@lancaironline.net Subject: [LML] TIT rise I have noticed a strange but reproducible issue with my TIT's (see EIS issues.pdf). In cruise and with a steady state power setting (EGT's, fuel flow, fuel pressure, man. pressure, rpm all constant), the TIT's climb over 50 degree F over a 1 hour period. They eventually reach 1650 degrees F and the alarms start to go off. I richen the mixture to keep the temperature below the recommend 1650. Once the mixture is richened and the TIT's fall below 1650, the TIT's do not continue to rise for the remainder of the flight. I would like to start flying LOP but the TIT rise makes the issue a little confusing. Anyone want to take a shot at this mystery? Steve Richard Lancair ES TSIO550 EIS 6000 engine monitor Steve, I fly LOP and observe that the fuel flow and EGTs/TIT gradually rise in the first hour of flight. I attribute this phenomenon to cooling of the fuel at altitude. The fuel is metered by volume, but burned by mass, so as the fuel cools and becomes denser, the mixture becomes slightly richer. When I reset the mixture after the period of initial cooling, the setup remains stable. It is not clear to me if the data you presented is obtained LOP or ROP. If you are ROP, my explanation could not be correct, but I would suggest that you run LOP and see what happens. You've confirmed correct magneto timing, right? To operate LOP, set your MP and RPM where you want them (32/2400? I use 30/2500 in a TNIO 550), then prelean to 200 ROP, then use the lean find mode on your monitor and lean past peak until the richest cylinder is 60-100 LOP. See where your TITs end up. If your TIT exceeds 1650 (which I think will be unlikely in this regime), lean further. Jonathan Fuller ------=_NextPart_000_068A_01CA50C7.46EE0B40 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

My experience = corresponds with Steve Richard’s, and I agree with Jonathan Fuller’s analysis. I = run my IV-P (TSIO-550E) 100-120 lean of peak, at 2300 RPM and 27-28” MP depending on temp and altitude. I typically re-set the fuel flow 45-60 = minutes after level-off and it stays very steady from that point on. Just came = east to Manassas (HEF) in two hops from Inyokern (IYK), CA, stopping in = Arlington, TX (GKY). This gradual increase in TITs over the first 45 minutes or so = happened on both legs at FL 210/190; very steady after that…reset and no = change until descent time, although the OAT cooled at least 20 more degrees on = the second leg to HEF.

 

Bob

 

From:= Lancair = Mailing List [mailto:lml@lancaironline.net] On Behalf Of Jonathan = Fuller
Sent: Monday, October 19, 2009 9:19 AM
To: lml@lancaironline.net
Subject: [LML] TIT rise

 

I have noticed a strange but reproducible issue = with my TIT's (see EIS issues.pdf).  In cruise and with a steady state power = setting (EGT's, fuel flow, fuel pressure, man. pressure, rpm all constant), = the TIT's climb over 50 degree F over a 1 hour period.  They eventually reach 1650 degrees F and the alarms start to go off.  I = richen the mixture to keep the temperature below the recommend 1650.  Once = the mixture is richened and the TIT's fall below 1650, the TIT's = do not continue to rise for the remainder of the flight. =

&n= bsp;

I would like to start flying LOP but the TIT rise = makes the issue a little confusing.

 

A= nyone want to take a shot at this mystery? 

 

Steve Richard

 

Lancair ES

TSIO550

EIS 6000 engine monitor

 

Steve,

I fly LOP and observe that the fuel flow and = EGTs/TIT  gradually rise in the first hour of flight.  I attribute this phenomenon to cooling of the fuel at altitude.  The fuel is metered = by volume, but burned by mass, so as the fuel cools and becomes denser, the mixture becomes slightly richer.  When I reset the mixture after = the period of initial cooling, the setup remains stable.

 

It is not clear to me if the data you presented is = obtained LOP or ROP.  If you are ROP, my explanation could not be correct, = but I would suggest that you run LOP and see what happens.  You’ve confirmed correct magneto timing, right? 

 

To operate LOP, set your MP and RPM where you want = them (32/2400? I use 30/2500 in a TNIO 550), then prelean to 200 ROP, then = use the lean find mode on your monitor and lean past peak until the richest = cylinder is 60-100 LOP.  See where your TITs end up.  If your TIT exceeds = 1650 (which I think will be unlikely in this regime), lean = further.

 

Jonathan Fuller

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