Return-Path: Received: from [199.185.220.240] (HELO priv-edtnes46.telusplanet.net) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP id 2633482 for flyrotary@lancaironline.net; Sun, 12 Oct 2003 03:16:25 -0400 Received: from Endurance ([209.53.248.123]) by priv-edtnes46.telusplanet.net (InterMail vM.5.01.06.05 201-253-122-130-105-20030824) with SMTP id <20031012070645.RZLE14548.priv-edtnes46.telusplanet.net@Endurance> for ; Sun, 12 Oct 2003 01:06:45 -0600 From: "Haywire" To: "Rotary motors in aircraft" Subject: RE: [FlyRotary] Re: EWP - Success at last? Date: Sun, 12 Oct 2003 00:06:38 -0700 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Importance: Normal In-Reply-To: > If we're talking about elegance here, I'd almost rather see > something in "Y" form where the valve is a butterfly between two > inlets and combines the flows into a single outlet. Then only one > valve is needed. If only one pump is pushing, the butterfly valve > would block reverse flow into the other pump. If both pumps are > pushing the butterfly valve would open relatively evenly > (assuming equal flow from both pumps) and allow both to flow. > Last week before I flew with the existing single pump arrangement, I built exactly what you're talking about here. It is a "T" that combines the flows with a flapper valve. It took about 2 hours to weld it up from alum and hand shape it. (last weeks talk of mills and lathes really had me wishing:-). I've not tested it yet but I had it on hand to install with the replacement pump if it proved necessary. It weighs 3/4lb. Fortunately it has not been required so I've opted to keep it simple for now, however extended flight over water or other inhospitable terrain may make this a desirable feature. I've just got to be certain that it will not add another failure mode to the system. I took some pics of it but they are of the olde fashioned film variety and I've not yet developed them. S. Todd Bartrim Turbo 13B RV-9Endurance C-FSTB http://www3.telus.net/haywire/RV-9/C-FSTB.htm "Whatever you vividly imagine, Ardently desire, Sincerely believe in, Enthusiastically act upon, Must inevitably come to pass".