Return-Path: Received: from [129.116.87.170] (HELO MAIL01.austin.utexas.edu) by logan.com (CommuniGate Pro SMTP 4.3c1) with ESMTP id 728277 for flyrotary@lancaironline.net; Mon, 14 Feb 2005 11:10:02 -0500 Received-SPF: none receiver=logan.com; client-ip=129.116.87.170; envelope-from=mark.steitle@austin.utexas.edu X-MimeOLE: Produced By Microsoft Exchange V6.5.7226.0 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----_=_NextPart_001_01C512AF.87DE182A" Subject: RE: [FlyRotary] Re: Bad day at the airport Date: Mon, 14 Feb 2005 10:09:15 -0600 Message-ID: <87DBA06C9A5CB84B80439BA09D86E69EC07F4E@MAIL01.austin.utexas.edu> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [FlyRotary] Re: Bad day at the airport Thread-Index: AcUSrWj/WIrjDZ/FSG+GZvDOxQKRgQAAGafg From: "Mark R Steitle" To: "Rotary motors in aircraft" This is a multi-part message in MIME format. ------_=_NextPart_001_01C512AF.87DE182A Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable =20 Paul, It looks like the group has focused in on the fuel system, or more specifically the sump tank as the likely culprit. I suspected you might have been running mogas. Its my understanding that auto fuel has a much lower vapor pressure than avgas and is therefore more likely to vapor lock. =20 =20 Just a SWAG, but I think the engine and related systems got hot enough to heat the fuel in the fuel rails so that once it passed the pressure regulator (pressure drop) it started to boil, similar to when you open a hot soda. With the return fuel going to an unvented tank, the boiling fuel expanded enough to cause pressure in the header tank so as to prevent fresh fuel from flowing into the tank. Eventually, the header tank ran dry and the engine quit. You sure handled the situation like a pro. Hope I never have to face that scenario. =20 Mark S.=20 =20 =20 =20 Hi, Mark...my humblest appologies for taking so long to respond. I am whittling down the 200 plus messages in my inbox. I was using auto fuel (regular). I have a fuel return line and it goes to the top of my aluminum sump tank that is located on the cool side of the firewall (inside the cabin, behind the rear seat). The return line is -8 in size. Hope this helps. Paul Conner ------_=_NextPart_001_01C512AF.87DE182A Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

 

Paul,

It looks like the group has focused = in on the fuel system, or more specifically the sump tank as the likely = culprit.  I suspected you might have been running mogas.  Its my understanding = that auto fuel has a much lower vapor pressure than avgas and is therefore = more likely to vapor lock. 

 

Just a SWAG, but I think the engine = and related systems got hot enough to heat the fuel in the fuel rails so = that once it passed the pressure regulator (pressure drop) it started to boil, = similar to when you open a hot soda.  With the return fuel going to an = unvented tank, the boiling fuel expanded enough to cause pressure in the header tank so = as to prevent fresh fuel from flowing into the tank.  Eventually, the = header tank ran dry and the engine quit.  You sure handled the situation = like a pro.  Hope I never have to face that = scenario.

 

Mark S. =

 

  =

 

Hi, Mark...my humblest appologies for taking so long = to respond.  I am whittling down the 200 plus messages in my = inbox.  I was using auto fuel (regular). I have a fuel return line and it goes to = the top of my aluminum sump tank that is located on the cool side of the = firewall (inside the cabin, behind the rear seat). The return line is -8 in = size.  Hope this helps.  Paul Conner

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