X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [65.173.216.67] (account marv@lancaironline.net) by logan.com (CommuniGate Pro WebUser 5.0c2) with HTTP id 721741 for lml@lancaironline.net; Wed, 14 Sep 2005 13:15:43 -0400 From: "Marvin Kaye" Subject: Re: [LML] tire pressures To: lml X-Mailer: CommuniGate Pro WebUser v5.0c2 Date: Wed, 14 Sep 2005 13:15:43 -0400 Message-ID: In-Reply-To: <023e01c5b932$ebc6e0f0$4201a8c0@lowell> References: <023e01c5b932$ebc6e0f0$4201a8c0@lowell> X-Priority: 3 MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format="flowed" Content-Transfer-Encoding: 8bit Posted for "Lowell Fitt" : This might ba apples and oranges, but the most common cause in shimmy in a tail wheel airplane is incorrect pivot axis angle. One way we can confirm that to be the problem is to remove some pressure on the tail wheel spring by giving a little nose down elevator. This will usually cause the shimmy to stop as it allows the spring to straighten a bit which gives a more aft leaning pivot axis. Remember the shopping cart that shimmies - pivot angle. We just mounted the nosewheel strut on our IV and it called for a .5 - 1 degree forward divergence from vertical. With the tailwheel shimmy in mind, the 1 degree would be preferable. It places the tire contact with the ground further aft of the pivot axis. Lowell