X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 2 [X] Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 07 Apr 2007 17:08:24 -0400 Message-ID: X-Original-Return-Path: Received: from vms048pub.verizon.net ([206.46.252.48] verified) by logan.com (CommuniGate Pro SMTP 5.1.8) with ESMTP id 1973013 for lml@lancaironline.net; Sat, 07 Apr 2007 12:58:40 -0400 Received: from [192.168.0.104] ([75.82.233.22]) by vms048.mailsrvcs.net (Sun Java System Messaging Server 6.2-6.01 (built Apr 3 2006)) with ESMTPA id <0JG5003BT0HIND75@vms048.mailsrvcs.net> for lml@lancaironline.net; Sat, 07 Apr 2007 11:58:31 -0500 (CDT) X-Original-Date: Sat, 07 Apr 2007 09:59:38 -0700 From: Bryan Wullner Subject: Re: [LML] Re: Testing for fuel leaks and fuel probes to use In-reply-to: X-Original-To: "Lancair Mailing List" X-Original-Message-id: <34306D00-F289-420B-91DA-99006D3E212B@verizon.net> MIME-version: 1.0 (Apple Message framework v752.3) X-Mailer: Apple Mail (2.752.3) Content-type: multipart/alternative; boundary=Apple-Mail-1-89482984 References: --Apple-Mail-1-89482984 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed I would be interested in the device. Bryan On Apr 7, 2007, at 9:32 AM, Gary Casey wrote: > Turns out we build pressure sensors that are used for measuring > fluid level (the most fun one is for the sewage holding tank on the > Airbus 320). Unfortunately, there are lots of problems with using > this method for fuel level. One is that the pressure is relatively > low - if the full fuel level is 1 foot above the sensor the > pressure is only about 0.4 psi, so you need a fairly low pressure > sensor, but that's not too bad. The sensor needs to be vented and > it should be vented to the vapor in the tank just in case the tank > vent system isn't perfect, and most Lancair system aren't because > the vent is pointed forward, slightly pressurizing the tank. > However, if any liquid fuel gets in the vent the accuracy is > destroyed - and maybe the sensor as well. Also, the pressure > sensor would presumably be located at the wing root, so there would > be substantial errors induced caused by out-of-level conditions > (slips). And, of course, the sensor has to be compatible with > liquid gasoline. > > I have been playing around with just such a device that can be used > for checking fuel level during a preflight, especially useful on a > low-wing plane where the dipstick doesn't always reach the fuel. I > rigged up a pressure sensor with a fitting that can be pushed > against the quick-drain and it will read fuel level, either by > displaying a pressure number, or actual fuel quantity by > calibrating it for the specific airplane. A few details need to be > sorted out, but it can be made to be fairly accurate; within about > 1 percent. If the plane is parked where it isn't level there would > be an error, but that condition isn't the norm. And there is no > problem with venting the sensor to atmosphere as the tank shouldn't > be pressurized while standing still. What I don't know is whether > anyone would be willing to buy such a thing (probably about $100). > Might be a good stocking stuffer for the pilot who has everything > else. Any potential interest? > > Gary Casey > N224SG > >> >> From: "Mark Steitle" >> Date: April 5, 2007 6:38:53 AM PDT >> To: lml@lancaironline.net >> Subject: Re: [LML] Re: Testing for fuel leaks and fuel probes to use >> >> >> Bryan, >> I heard of one builder that used pressure sensors as fuel level >> sensors. I think they were rated at 0-5psi. Sounds like this may >> be a solution for you too. >> >> Mark S. >> > --Apple-Mail-1-89482984 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=ISO-8859-1 I would be interested in the = device.

Bryan


On Apr 7, = 2007, at 9:32 AM, Gary Casey wrote:

Turns out = we build pressure sensors that are used for measuring fluid level (the = most fun one is for the sewage holding tank on the Airbus 320).=A0 = Unfortunately, there are lots of problems with using this method for = fuel level.=A0 One is that the pressure is relatively low - if the full = fuel level is 1 foot above the sensor the pressure is only about 0.4 = psi, so you need a fairly low pressure sensor, but that's not too bad.=A0 = The sensor needs to be vented and it should be vented to the vapor in = the tank just in case the tank vent system isn't perfect, and most = Lancair system aren't because the vent is pointed forward, slightly = pressurizing the tank. =A0However, if any liquid fuel gets in the vent = the accuracy is destroyed - and maybe the sensor as well. =A0Also, the = pressure sensor would presumably be located at the wing root, so there = would be substantial errors induced caused by out-of-level conditions = (slips). =A0And, of course, the sensor has to be compatible with liquid = gasoline.

I have = been playing around with just such a device that can be used for = checking fuel level during a preflight, especially useful on a low-wing = plane where the dipstick doesn't always reach the fuel. =A0I rigged up a = pressure sensor with a fitting that can be pushed against the = quick-drain and it will read fuel level, either by displaying a pressure = number, or actual fuel quantity by calibrating it for the specific = airplane. =A0A few details need to be sorted out, but it can be made to = be fairly accurate; within about 1 percent.=A0 If the plane is parked = where it isn't level there would be an error, but that condition isn't = the norm. =A0And there is no problem with venting the sensor to = atmosphere as the tank shouldn't be pressurized while standing still. = =A0What I don't know is whether anyone would be willing to buy such a = thing (probably about $100). =A0Might be a good stocking stuffer for the = pilot who has everything else.=A0 Any potential interest?

Gary = Casey
N224SG


From: = "Mark Steitle" <msteitle@gmail.com>
=
Date: April 5, 2007 6:38:53 AM = PDT
To: lml@lancaironline.net
Subject: Re: [LML] Re: Testing for fuel leaks = and fuel probes to use


=
Bryan,
I heard of one builder that used pressure = sensors=A0as fuel level sensors.=A0 I think they were rated at 0-5psi.=A0 = Sounds like=A0this may be a solution for you too.
=A0
=
Mark = S.



= = --Apple-Mail-1-89482984--