X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 06 Jan 2010 09:51:16 -0500 Message-ID: X-Original-Return-Path: Received: from imr-ma01.mx.aol.com ([64.12.206.39] verified) by logan.com (CommuniGate Pro SMTP 5.3.0) with ESMTP id 4066684 for lml@lancaironline.net; Wed, 06 Jan 2010 09:46:58 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.206.39; envelope-from=MikeEasley@aol.com Received: from imo-da01.mx.aol.com (imo-da01.mx.aol.com [205.188.169.199]) by imr-ma01.mx.aol.com (8.14.1/8.14.1) with ESMTP id o06EkFXw008124 for ; Wed, 6 Jan 2010 09:46:15 -0500 Received: from MikeEasley@aol.com by imo-da01.mx.aol.com (mail_out_v42.5.) id q.c34.6b9e439b (43904) for ; Wed, 6 Jan 2010 09:46:13 -0500 (EST) Received: from MikeNotebook (c-75-71-55-189.hsd1.co.comcast.net [75.71.55.189]) by cia-dc07.mx.aol.com (v127.7) with ESMTP id MAILCIADC071-ab804b44a230fd; Wed, 06 Jan 2010 09:46:09 -0500 X-Original-Date: Wed, 6 Jan 2010 07:45:17 -0700 From: mikeeasley Subject: Re: [LML] Re: Fuel Planning - Capacitance probes X-Original-To: "Lancair Mailing List" In-Reply-To: X-Original-Message-ID: References: X-Mailer: Nexus Desktop Client 3.1.20.1 MIME-Version: 1.0 Content-Type: MULTIPART/alternative; BOUNDARY=4edaf46b-b47d-4483-be20-47312122a4e0 Content-Transfer-Encoding: 8bit X-AOL-IP: 75.71.55.189 X-Spam-Flag:NO X-AOL-SENDER: MikeEasley@aol.com --4edaf46b-b47d-4483-be20-47312122a4e0 Content-Type: TEXT/plain; charset=us-ascii Gary, Since the capacitance probes seem to be fairly reliable in our small sampling, but the potential for inaccuracies is there, I'm curious about a couple things. If we calibrate our probes with the engine off, at ~12V in my airplane, how would the fuel level readings change in flight with ~13.8V in the electrical system? How much does temperature effect the fuel level readings? Say from 30F to 80F. Also, I did some digging on water being dissolved in 100LL. It appears that they have an additive that causes dissolved water to separate from the fuel and collect at the bottom of the storage container (at any step along the way including our wing tanks). I hate to use the word "practical" when talking to an engineer, but from a practical sense how much water can we have dissolved in our 100LL? And is this a bigger problem for the turbine guys? http://chevronglobalaviation.com/docs/aviation_tech_review.pdf http://www.gewater.com/industries/refining_fuel/fuel_additives/dehazers.jsp Mike Easley Colorado Springs --4edaf46b-b47d-4483-be20-47312122a4e0 Content-Type: TEXT/html; charset=utf-8 Content-Transfer-Encoding: 8BIT
Gary,
 
Since the capacitance probes seem to be fairly reliable in our small sampling, but the potential for inaccuracies is there, I'm curious about a couple things.
 
If we calibrate our probes with the engine off, at ~12V in my airplane, how would the fuel level readings change in flight with ~13.8V in the electrical system?
 
How much does temperature effect the fuel level readings?  Say from 30F to 80F.
 
Also, I did some digging on water being dissolved in 100LL.  It appears that they have an additive that causes dissolved water to separate from the fuel and collect at the bottom of the storage container (at any step along the way including our wing tanks).  I hate to use the word "practical" when talking to an engineer, but from a practical sense how much water can we have dissolved in our 100LL?  And is this a bigger problem for the turbine guys?
 
 
 
Mike Easley
Colorado Springs
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