Return-Path: Sender: (Marvin Kaye) To: lml Date: Fri, 01 Aug 2003 20:49:47 -0400 Message-ID: X-Original-Return-Path: Received: from falcon.mail.pas.earthlink.net ([207.217.120.74] verified) by logan.com (CommuniGate Pro SMTP 4.1) with ESMTP id 2508776 for lml@lancaironline.net; Fri, 01 Aug 2003 02:41:04 -0400 Received: from sdn-ap-007watacop0088.dialsprint.net ([65.176.64.88] helo=f3g6s4) by falcon.mail.pas.earthlink.net with smtp (Exim 3.33 #1) id 19iTb5-0005WX-00 for lml@lancaironline.net; Thu, 31 Jul 2003 23:41:03 -0700 X-Original-Message-ID: <00d701c357f8$b93881e0$5840b041@f3g6s4> Reply-To: "Dan Schaefer" From: "Dan Schaefer" X-Original-To: "Lancair list" Subject: Re: MT prop questions X-Original-Date: Thu, 31 Jul 2003 23:47:05 -0700 MIME-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1158 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1165 To those asking why going to an MT prop might move the cg forward. It depends on what you're replacing. My LNC2 (early 235) started life with a fixed pitch wood prop with various heavy chunks (battery, hydro pump, etc.) arranged to get an acceptable weight and balance/cg set-up. The wood prop was subsequently replaced a with an electric C/S MT and the airplane has also gone a bit nose heavy. The reason is simple: the wood prop and spinner probably weighed in around 17 - 18 pounds and the MT more like 27 - 30 (maybe more, I've forgotton the exact numbers). Granted, the composite blades on the MT are light weight but the hub is HEAVY (in comparison, that is). As I said, I don't know exactly what the hub weighs but it looks like it was designed for a 300 HP engine. I love German engineers - they build things to last (a few pounds more than absolutely needed, but hey! who's counting)? (My wife's '82 Mercedes 240 Diesel has 260,000 miles on it and it still hums right along, so if my MT hub is a bit stout, I can live with it)! Only problem noted: Had to beef up the pitch-trim springs just a bit to keep from running out of nose-up trim during slow flight (landing phase). Never run out of elevator authority, just couldn't trim out the stick pressure in the pattern. There were no discernable negative effects on other flight regimes from the noseward shift in cg. Dan Schaefer LNC2 (Early 235)