X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 09 Oct 2013 15:28:24 -0400 Message-ID: X-Original-Return-Path: Received: from mail-ob0-f178.google.com ([209.85.214.178] verified) by logan.com (CommuniGate Pro SMTP 6.0.7) with ESMTPS id 6508701 for lml@lancaironline.net; Wed, 09 Oct 2013 14:31:16 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.214.178; envelope-from=toddlong1@gmail.com Received: by mail-ob0-f178.google.com with SMTP id uz6so930294obc.23 for ; Wed, 09 Oct 2013 11:30:40 -0700 (PDT) X-Received: by 10.182.165.42 with SMTP id yv10mr51648obb.92.1381343440247; Wed, 09 Oct 2013 11:30:40 -0700 (PDT) X-Original-Return-Path: Received: from [10.253.248.223] (242.sub-174-238-97.myvzw.com. [174.238.97.242]) by mx.google.com with ESMTPSA id z5sm12526560obg.13.1969.12.31.16.00.00 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 09 Oct 2013 11:30:39 -0700 (PDT) Subject: Re: [LML] Re: Removing vacuum pump? References: From: Todd Long Content-Type: text/plain; charset=us-ascii X-Mailer: iPhone Mail (11A501) In-Reply-To: X-Original-Message-Id: <4162DFB5-48C0-4C15-87B8-A981A1026785@gmail.com> X-Original-Date: Wed, 9 Oct 2013 13:30:36 -0500 X-Original-To: Lancair Mailing List Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 (1.0) Although the outflow valve is held open with the dump valve switch on, it is= not nearly as far open as it is when using the vacuum line. Typing and grammar errors courtesy of Siri and the iPhone. > On Oct 9, 2013, at 13:13, Colyn Case wrote: >=20 > maybe Pete (leapfrog) can chime in here but I don't really understand why D= ukes put that in there. You could have the dump switch on during takeoff, a= nd there's another way to wire it that holds the outflow valve full open. >=20 > On Oct 9, 2013, at 11:13 AM, Craig Berland wrote: >=20 > I have an all-electric airplane as well and chose to not have any vacuum s= upplied to the Dukes valve. The only difference is the rate in which pressu= rization starts building in the cabin on takeoff roll. Once airborne, vacuu= m has no effect on the pressurization system. I choose to apply power a li= ttle more slowly than some pilots. This prevents any pressurization discomf= ort and typically I don't need any right brake to hold centerline. Takeoff d= istance is not an issue. If I can land there, I can easily takeoff there. I= know one pilot who has developed an electronic circuit to control a small e= lectric vacuum pump based on the landing gear position. So there are severa= l options. In my opinion, keeping the engine driven pump is the least desir= able. >=20 > Craig Berland > N7VG >=20 >=20 > Hello Dico, > You will need a vacuum port to the Dukes pressure valve for the pressuriza= tion to work correctly, I do not have any gyro instruments either but I need= ed to install an electric vacuum pump near the Dukes valve > Kamal T > N1104T >=20 >=20 >=20 >=20 > -- > For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.htm= l >=20 >=20 > -- > For archives and unsub http://mail.lancaironline.net:81/lists/lml/List.htm= l