X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sun, 22 Mar 2009 16:13:36 -0400 Message-ID: X-Original-Return-Path: Received: from smtp-auth-04.mx.pitdc1.expedient.net ([206.210.66.137] verified) by logan.com (CommuniGate Pro SMTP 5.2.13) with ESMTPS id 3554482 for lml@lancaironline.net; Fri, 20 Mar 2009 22:07:48 -0400 Received-SPF: none receiver=logan.com; client-ip=206.210.66.137; envelope-from=rpastusek@htii.com Received: from HTBOB001 (static-71-178-198-10.washdc.fios.verizon.net [71.178.198.10]) by smtp-auth-04.mx.pitdc1.expedient.net (Postfix) with ESMTPA id 563D7E4578 for ; Fri, 20 Mar 2009 22:07:13 -0400 (EDT) From: "Robert Pastusek" X-Original-To: "'Lancair Mailing List'" Subject: FW: [LML] Fuel selector Valve question X-Original-Date: Fri, 20 Mar 2009 22:07:09 -0400 X-Original-Message-ID: <027401c9a9c9$be3450b0$3a9cf210$@com> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0275_01C9A9A8.3722B0B0" X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AcmpcqI8I0++c9eIRBWgGF8i1ISQTQAU9KqA Content-Language: en-us This is a multipart message in MIME format. ------=_NextPart_000_0275_01C9A9A8.3722B0B0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Bryan Wullner wrote: I would like to be able to run my engine off my wing tanks if needed but I don't want to re-plumb the wings with 3/8" lines. Can I connect the 1/4" wing tank lines into a "T" with a 3/8" exit and run the line to the selector valve? Essentially the wings would not be able to be selected but they would feed at the same time equally. Bryan, I'd strongly discourage you from doing this.even more strongly if you are feeding a fuel-injected engine. There are probably many more on the LML that will also advise on this, but the main reason not to do this is that your proposed configuration allows air to be easily pulled into the fuel system, especially during the critical take off phase of flight. Even a small amount of yaw during takeoff can un-port one of the wing tanks, allowing air to be drawn into the lines and pushed to the engine. Almost guaranteed engine stoppage, and if it's a fuel injected engine, typically many seconds to restart-if you recognize and correct the problem. If you don't, the engine won't restart before you're on the ground. L The above is one of the reasons your airplane includes a header tank in the first place. This is one area where you'd do well to stick by the Lancair design. Bob ------=_NextPart_000_0275_01C9A9A8.3722B0B0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Bryan Wullner wrote:

 

I would like to be able to run my engine off my = wing tanks if needed but I don't want to re-plumb the wings with 3/8" lines.  Can I connect the 1/4" wing tank lines into a "T" = with a 3/8" exit and run the line to the selector valve?  Essentially = the wings would not be able to be selected but they would feed at the same = time equally. 

 

Bryan,

I’d strongly discourage you from doing = this…even more strongly if you are feeding a fuel-injected engine. There are = probably many more on the LML that will also advise on this, but the main reason = not to do this is that your proposed configuration allows air to be easily = pulled into the fuel system, especially during the critical take off phase of = flight. Even a small amount of yaw during takeoff can un-port one of the wing tanks, = allowing air to be drawn into the lines and pushed to the engine. Almost = guaranteed engine stoppage, and if it’s a fuel injected engine, typically = many seconds to restart—if you recognize and correct the problem. If = you don’t, the engine won’t restart before you’re on the ground… = L

 

The above is one of the reasons your airplane includes a = header tank in the first place… This is one area where you’d do = well to stick by the Lancair design.


Bob

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