X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 25 Aug 2007 10:07:23 -0400 Message-ID: X-Original-Return-Path: Received: from elasmtp-junco.atl.sa.earthlink.net ([209.86.89.63] verified) by logan.com (CommuniGate Pro SMTP 5.1.11) with ESMTP id 2283265 for lml@lancaironline.net; Fri, 24 Aug 2007 19:10:41 -0400 Received-SPF: none receiver=logan.com; client-ip=209.86.89.63; envelope-from=panelmaker@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=tefMaff7yScmYt7CsmYxeY1a3tGX9IRr71PnMbPgre6b7bViEULhJ1wgEiEPFB7O; h=Received:From:To:Subject:Date:MIME-Version:Content-Type:X-Mailer:X-MimeOLE:In-Reply-To:Thread-Index:Message-ID:X-ELNK-Trace:X-Originating-IP; Received: from [98.196.16.146] (helo=DELL8300) by elasmtp-junco.atl.sa.earthlink.net with asmtp (Exim 4.34) id 1IOiI2-0006BZ-0x for lml@lancaironline.net; Fri, 24 Aug 2007 19:10:06 -0400 From: "Jim Nordin" X-Original-To: "'Lancair Mailing List'" Subject: Wing leak X-Original-Date: Fri, 24 Aug 2007 18:11:10 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00A3_01C7E67A.2690F060" X-Mailer: Microsoft Office Outlook, Build 11.0.6353 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3138 In-Reply-To: Thread-Index: AcfmkNEI4+OkS3fMQmq35k1s5fsYeQADOoLQ X-Original-Message-ID: X-ELNK-Trace: bdfc62829fd2a80cc8ad50643b1069f8239a348a220c26094090987d837039e3e4e0d0b44b61c700667c3043c0873f7e350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 98.196.16.146 This is a multi-part message in MIME format. ------=_NextPart_000_00A3_01C7E67A.2690F060 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit And . balloons leak. Even really good balloons can leak . much less the party ones we buy at Target. You might want to try a manometer instead, you know . a marked "U" channel with an appropriate fluid in it. Now take all the other variables into account and you'll be close. Of course we don't have an ideal gas to use pv=nrt accurately, but for our purposes it's close enough. This method substantially removes the question of changing volume due to balloon relaxation et al. Or flush the inside of the tank with Freon (don't let the FEDs know), pressurize it a little, seal it, then use a "sniffer" to detect the very smallest micro leak. Flow plenty of air over the wing areas for a while to remove residual Freon pockets. Freon's molecular size (critical dimension is about 5.3 angstroms) is close to pentane (6 angstroms I think I remember) which means, if you can flow Freon, you can flow pentane. So if you find a leak using a sniffer, you might have a gasoline leak there too. Hey, I might be wrong about the numbers . it's been a long time since using these dimensions etc, but the sniffer should work even if the numbers are wrong. This method removes the volumetric, atmospheric and temperature variation issues altogether. Just make sure there's positive pressure in the tank when searching for that micro amount of Freon. Jim ------=_NextPart_000_00A3_01C7E67A.2690F060 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

And … balloons leak. Even really good balloons can leak … much less the = party ones we buy at Target. You might want to try a manometer instead, you know = … a marked “U” channel with an appropriate fluid in it. Now take = all the other variables into account and you’ll be close. Of course we = don’t have an ideal gas to use pv=3Dnrt accurately, but for our purposes = it’s close enough. This method substantially removes the question of changing = volume due to balloon relaxation et al.

 

Or flush the inside of the tank with Freon (don’t let the FEDs know), = pressurize it a little, seal it, then use a “sniffer” to detect the = very smallest micro leak. Flow plenty of air over the wing areas for a while = to remove residual Freon pockets. Freon’s molecular size (critical = dimension is about 5.3 angstroms) is close to pentane (6 angstroms I think I = remember) which means, if you can flow Freon, you can flow pentane. So if you find = a leak using a sniffer, you might have a gasoline leak there too. Hey, I might = be wrong about the numbers … it’s been a long time since using = these dimensions etc, but the sniffer should work even if the numbers are = wrong. This method removes the volumetric, atmospheric and temperature variation = issues altogether. Just make sure there’s positive pressure in the tank = when searching for that micro amount of Freon.

 

Jim

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