X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 21 Apr 2010 21:20:19 -0400 Message-ID: X-Original-Return-Path: Received: from imr-mb01.mx.aol.com ([64.12.207.164] verified) by logan.com (CommuniGate Pro SMTP 5.3.5) with ESMTP id 4228406 for lml@lancaironline.net; Tue, 20 Apr 2010 17:06:44 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.207.164; envelope-from=MikeEasley@aol.com Received: from imo-da03.mx.aol.com (imo-da03.mx.aol.com [205.188.169.201]) by imr-mb01.mx.aol.com (8.14.1/8.14.1) with ESMTP id o3KL65ox030910 for ; Tue, 20 Apr 2010 17:06:05 -0400 Received: from MikeEasley@aol.com by imo-da03.mx.aol.com (mail_out_v42.9.) id q.dea.356cbe9 (45278) for ; Tue, 20 Apr 2010 17:06:01 -0400 (EDT) Received: from smtprly-mc01.mx.aol.com (smtprly-mc01.mx.aol.com [64.12.95.97]) by cia-mc03.mx.aol.com (v128.3) with ESMTP id MAILCIAMC038-d3c74bce172ba2; Tue, 20 Apr 2010 17:06:01 -0400 Received: from webmail-m054 (webmail-m054.sim.aol.com [64.12.158.154]) by smtprly-mc01.mx.aol.com (v128.3) with ESMTP id MAILSMTPRLYMC011-d3c74bce172ba2; Tue, 20 Apr 2010 17:05:47 -0400 References: X-Original-To: lml@lancaironline.net Subject: Re: [LML] Re: Fuel Pressure Setup X-Original-Date: Tue, 20 Apr 2010 17:05:46 -0400 X-AOL-IP: 75.70.114.179 In-Reply-To: X-MB-Message-Source: WebUI MIME-Version: 1.0 From: mikeeasley@aol.com X-MB-Message-Type: User Content-Type: multipart/alternative; boundary="--------MB_8CCAEE461D1E144_1E28_4699_webmail-m054.sysops.aol.com" X-Mailer: AOL Webmail 31509-STANDARD Received: from 75.70.114.179 by webmail-m054.sysops.aol.com (64.12.158.154) with HTTP (WebMailUI); Tue, 20 Apr 2010 17:05:46 -0400 X-Original-Message-Id: <8CCAEE461CABD24-1E28-228E@webmail-m054.sysops.aol.com> X-Spam-Flag:NO X-AOL-SENDER: MikeEasley@aol.com ----------MB_8CCAEE461D1E144_1E28_4699_webmail-m054.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="us-ascii" I think conventional wisdom is to display unmetered fuel pressure on your= engine monitor. At least that's the way mine is set up. That's the numb= er that's listed in the TCM operating limitations. As for the setup using= the SID, fuel flow is what you should pay attention to at the top end and= use the higher end of the range as the minimum. Since we take off with= our low boost on, I set up my engine to be at the upper limit of 27.3 wit= hout the boost pump on and I get another 1.~ GPH with the low boost. TCM= says the unmetered pressure is just for reference when setting up the fue= l injection, that you should use metered pressure and fuel flow. After some investigation, I believe there's a direct corrrelation between= metered pressure and fuel flow and a very close correlation between unmet= ered fuel pressure and fuel flow. I took several hours of data recorded= by my engine monitor and imported the data into Excel and compared the nu= mbers and the numbers move within the accuracy of the measurements. With= this correlation, I believe you could set up your fuel flow to the right= number and assume your metered fuel pressure is correct. The one big ass= umption is whether there's any leakage or blockage in the system. By chec= king the metered and unmetered pressures and fuel flow, you have a way of= confirming that all the components are working correctly. Bottom line, follow the procedure exactly, or get someone to do it for you= . Mike Easley Colorado Springs -----Original Message----- From: Paul Bricker To: lml@lancaironline.net Sent: Tue, Apr 20, 2010 1:17 pm Subject: [LML] Re: Fuel Pressure Setup Dan, uel flow is what we really care about. It is roughly proportional to etered fuel pressure. I installed sensors that measure actual fuel flow so etered fuel pressure is somewhat redundant. For these reasons I monitor nmetered fuel pressure. My logic is it may give me a warning of fuel pump ailure or fuel line contriction before it would be reflected in the fuel low.=20 Paul Bricker 63PB -----Original Message----- rom: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of Dan allin ent: Monday, April 19, 2010 1:39 PM o: lml@lancaironline.net ubject: [LML] Re: Fuel Pressure Setup While I think this is all good information, the original question Jon ad and I have is how to monitor fuel pressure. The setup procedure sing SID97 is a different issue. I think the more interesting uestion is does one monitor metered or unmetered fuel pressure in the ockpit. It seems that TCM and at least Coumbia (Cessna) ecommend/use metered and that Lancair generally sets up their ircraft to use unmetered. I haven't gotten a good answer as to why nd what the advantages and disadvanages are. Obviously the values re different, but they are measuring essentially the same thing. Can anyone comment on what advantage/disadvantage there is to using a etered vs unmetered source for you fuel pressure measurement while lying. Dan Ballin EG2 #286 -- or archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html - or archives and unsub http://mail.lancaironline.net:81/lists/lml/List.html ----------MB_8CCAEE461D1E144_1E28_4699_webmail-m054.sysops.aol.com Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset="us-ascii"
I think conventional wisdom is to display unmetered fuel pressure on= your engine monitor.  At least that's the way mine is set up. = That's the number that's listed in the TCM operating limitations. = As for the setup using the SID, fuel flow is what you should pay attentio= n to at the top end and use the higher end of the range as the minimum.&nb= sp; Since we take off with our low boost on, I set up my engine to be at= the upper limit of 27.3 without the boost pump on and I get another 1.~= GPH with the low boost.  TCM says the unmetered pressure is just for= reference when setting up the fuel injection, that you should use metered= pressure and fuel flow.
 
After some investigation, I believe there's a direct corrrelation bet= ween metered pressure and fuel flow and a very close correlation between= unmetered fuel pressure and fuel flow.  I took several hours of data= recorded by my engine monitor and imported the data into Excel and compar= ed the numbers and the numbers move within the accuracy of the measurement= s.  With this correlation, I believe you could set up your fuel flow= to the right number and assume your metered fuel pressure is correct.&nbs= p; The one big assumption is whether there's any leakage or bloc= kage in the system.  By checking the metered and unmetered pressures= and fuel flow, you have a way of confirming that all the components are= working correctly.
 
Bottom line, follow the procedure exactly, or get someone to do it fo= r you.
 
Mike Easley
Colorado Springs



-----Original Message-----
From: Paul Bricker <pbricker@att.net>
To: lml@lancaironline.net
Sent: Tue, Apr 20, 2010 1:17 pm
Subject: [LML] Re: Fuel Pressure Setup

Dan=
,
Fuel flow is what we really care about. It is roughly proportional to
metered fuel pressure. I installed sensors that measure actual fuel flow=
 so
metered fuel pressure is somewhat redundant. For these reasons I monitor
unmetered fuel pressure. My logic is it may give me a warning of fuel pump
failure or fuel line contriction before it would be reflected in the fuel
flow.=20

Paul Bricker
N63PB

-----Original Message-----
From: Lancair Mailing List [mail=
to:lml@lancaironline.net] On Behalf Of Dan
Ballin
Sent: Monday, April 19, 2010 1:39 PM
To: lml@lancaironline.net
Subject: [LML] Re: Fuel Pressure Setup

While I think this is all good information, the original question Jon
had and I have is how to monitor fuel pressure.  The setup procedure
using SID97 is a different issue.  I think the more interesting
question is does one monitor metered or unmetered fuel pressure in the
cockpit.  It seems that TCM and at least Coumbia (Cessna)
recommend/use metered and that Lancair generally sets up their
aircraft to use unmetered.  I haven't gotten a good answer as to why
and what the advantages and disadvanages are.  Obviously the values
are different, but they are measuring essentially the same thing.

Can anyone comment on what advantage/disadvantage there is to using a
metered vs unmetered source for you fuel pressure measurement while
flying.

Dan Ballin
LEG2 #286

--
For archives and unsub http://mail.lancaironline.net:81/lists/lml/L=
ist.html


--
For archives and unsub http://mail.lancaironline.net:81/lists/lml/L=
ist.html
----------MB_8CCAEE461D1E144_1E28_4699_webmail-m054.sysops.aol.com--