X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 08 Jul 2009 16:24:48 -0400 Message-ID: X-Original-Return-Path: Received: from [66.64.141.200] (HELO lucky.dts.local) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTP id 3749475 for lml@lancaironline.net; Wed, 08 Jul 2009 13:26:52 -0400 Received-SPF: none receiver=logan.com; client-ip=66.64.141.200; envelope-from=cjensen@dts9000.com Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable X-MimeOLE: Produced By Microsoft Exchange V6.5 Subject: RE: [LML] Re: Shimmy and engine mounts X-Original-Date: Wed, 8 Jul 2009 13:29:14 -0400 X-Original-Message-ID: <8984A39879F2F5418251CBEEC9C689B3E86F43@lucky.dts.local> In-Reply-To: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [LML] Re: Shimmy and engine mounts Thread-Index: Acn/33TXA7xUQa+ORxSRh7dNgMR6AgAEe1Kg From: "Chuck Jensen" X-Original-To: "Lancair Mailing List" The lower tire pressure increases the tire/road contact area, increasing = the amount of friction, which dampens the shimmy as it drains energy = away from the oscillation forces. =20 Chuck Jensen -----Original Message----- From: Lancair Mailing List [mailto:lml@lancaironline.net]On Behalf Of Dan Schaefer Sent: Wednesday, July 08, 2009 11:16 AM To: lml@lancaironline.net Subject: [LML] Re: Shimmy and engine mounts On my early 235, inflating the nose wheel tire to over 28 psi will=20 inevitably induce shimmy. No theories as to why and no guesses as to how = this might relate to other Lancairs, just the way it is for my LNC-2. I = wear=20 the shoulders off the nose tire a bit faster than I like but I like = shimmy=20 less. The strut was installed way back in about '93 so it's certainly an = early version - pre many updates - but it's pretty good and requires the = mimimum of maintenance (a bit of nitrogen maybe every three years). Go=20 figure. Regarding the pics of the ES engine mount for a Cont. 550, those joins = sure=20 don't look all that beefy! During my current inspection, I gave my = mounts=20 (Dynafocal type) a very close look as a result of the ongoing thread = and,=20 though the mount only has to hold up a little O-235 (and react no more = than=20 125 HP) the weld joins on my mount are way more robust than the ones in = the=20 pics. The airplane has about 1000 hours on it now and I have yet to see = an=20 engine mount crack. Looks like the mounts in the pics (and all like = them)=20 could really use some judicious re-engineering, particularly at the weld = joins. Dan Schaefer Early 235 -- N235SP=20 --=20 I am using the free version of SPAMfighter. We are a community of 6 million users fighting spam. SPAMfighter has removed 549 of my spam emails to date. Get the free SPAMfighter here: http://www.spamfighter.com/len The Professional version does not have this message -- For archives and unsub = http://mail.lancaironline.net:81/lists/lml/List.html