Return-Path: Received: from portal.udlp.com ([207.109.1.80]) by truman.olsusa.com (Post.Office MTA v3.5.1 release 219 ID# 0-52269U2500L250S0V35) with ESMTP id com for ; Tue, 29 Jun 1999 21:27:48 -0400 Received: from portal.udlp.com (root@localhost) by portal.udlp.com with ESMTP id UAA12744 for ; Tue, 29 Jun 1999 20:30:52 -0500 (CDT) Received: from ccmail.udlp.com ([10.1.6.254]) by portal.udlp.com with ESMTP id UAA12733 for ; Tue, 29 Jun 1999 20:30:52 -0500 (CDT) Received: from ccMail by ccmail.udlp.com (IMA Internet Exchange 3.12) id 0004AC25; Tue, 29 Jun 1999 20:28:10 -0500 From: CHRISTOPHER_ZAVATSON@udlp.com Date: Tue, 29 Jun 1999 18:21:31 -0500 Message-ID: <0004AC25.C21254@udlp.com> Subject: Nose wheel shimmy To: Lancair.list@olsusa.com X-Mailing-List: lancair.list@olsusa.com Mime-Version: 1.0 <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> There are two additional variables in the shimmy equation that I haven't seen anyone mention yet. The first is the preload applied to the nose wheel bearings. I don't have access to my manuals at the moment, but the nose wheel is not supposed to rotate more than x revolutions when spun by hand. Also, the amount of shimmy damping provided by the oleo strut varies from one to the next. I had the opportunity to check the rotational resistance of the strut on the factory 360 a while back. It was substantially lighter (about 50%) than mine. It must be a specific combination of all the factors mentioned that initiates a shimmy. I hope we can find that combination. Chris Zavatson N91CZ >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML homepage: http://www.olsusa.com/Users/Mkaye/maillist.html