Return-Path: Received: from pop3.olsusa.com ([63.150.212.2] verified) by logan.com (CommuniGate Pro SMTP 3.5.1) with ESMTP id 993796 for rob@logan.com; Sat, 22 Dec 2001 17:34:41 -0500 Received: from mail4.pe.net ([64.38.64.14]) by pop3.olsusa.com (Post.Office MTA v3.5.3 release 223 ID# 0-71866U8000L800S0V35) with ESMTP id com for ; Sat, 22 Dec 2001 16:10:10 -0500 Received: from ieee.org (IP-90-152.gst.pe.net [64.38.90.152]) by mail4.pe.net (8.11.6/8.11.3) with ESMTP id fBMLAqI08954 for ; Sat, 22 Dec 2001 13:10:53 -0800 (PST) Message-ID: <3C24F6CA.4D51DAD7@ieee.org> Date: Sat, 22 Dec 2001 13:10:34 -0800 From: "Charles R. Patton" Reply-To: charles.r.patton@ieee.org Reply-To: lancair.list@olsusa.com MIME-Version: 1.0 To: lancair.list@olsusa.com Subject: Re: Implications of a HOT pitot tube References: Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Mailing-List: lancair.list@olsusa.com <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> Ed, You asked, "Should I be thinking of mounting the pitot tube with a metal flange on a 8"x8" metal plate to dissipate some of the heat or are my concerns unwarranted?" I should have mentioned that the experience with melting Nylaflow I related was with a heated pitot on a Thorp T-18, an aluminum airplane. So I can't give first-hand experience in the LN2 styles. But as I related the experience of my A&E certainly gave me pause -- burning the chrome off of a heated pitot tube is extremely hot. He described it as leaving scars on your hand even if you just brush it. My gut feel is that it will easily soften epoxy construction. If our plane wasn't already built, I would certainly entertain a heat-sink plate such as you envision. Another thought would be to do a simple experiment. Take the pitot and mount it on a scrap of epoxy/glass comparable to the intended mounting position/method. Fire up the pitot from a storage battery (or car jumper cables) whichever comes easier and see what happens! Not elegant, but certainly will answer the question convincingly. If the results are frightening, report back to the list, and the list can start thinking "retrofit." Regards, Chas N360JM >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://members.olsusa.com/mkaye/maillist.html LML Builders' Bookstore: http://www.buildersbooks.com/lancair Please remember that purchases from the Builders' Bookstore assist with the management of the LML. Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>