Return-Path: Received: from mail.cruzio.com ([208.226.92.37]) by truman.olsusa.com (Post.Office MTA v3.1.2 release (PO203-101c) ID# 0-44819U2500L250S0) with ESMTP id AAA4943 for ; Thu, 1 Oct 1998 19:18:30 -0400 Received: from testelectronics.mail (sa-207-251-8-144.cruzio.com [207.251.8.144]) by mail.cruzio.com with SMTP id QAA17362 for ; Thu, 1 Oct 1998 16:18:26 -0700 (PDT) Received: from main [192.168.1.1] by testelectronics.mail [192.168.1.1] with SMTP (MDaemon.v2.5.rB.b2.32-R) for ; Thu, 01 Oct 98 16:13:17 -0700 Received: by localhost with Microsoft MAPI; Thu, 1 Oct 1998 16:13:16 -0700 Message-ID: <01BDED56.65BA7210.ed@testelectronics.com> From: Ed Armstrong Reply-To: "ed@testelectronics.com" To: "Lancair [Lancair.List@Olsusa.Com] (E-mail)" Subject: fiberglass and carbon fiber Date: Thu, 1 Oct 1998 16:13:15 -0700 Organization: Test Electronics X-Mailing-List: lancair.list@olsusa.com Mime-Version: 1.0 <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> A while ago I wrote: That means that the body of my plane is going to take up most of the stress, and my longeron is not going to do much of anything. Any one have a word of encouragement for me? Now that I thought about this more, I realize that the longeron is not supposed to be structurally used for load carrying. I think we are just too familiar with things needing frames, and the whole idea behind composite construction is to reduce framework by making the surface strong. The wings are flat and need spars to keep them from bending, but the fuselodge is big and round like a pipe. A pipe is a strong shape, yes it is a pipe with a hole cut in the side for the canopy cover, but it is still a strong shape. I imagine this as kind of unibody construction. The whole body acts to support forces. If you look under the longeron the whole body is carbon fiber over honeycomb material. As we all know, the carbon fiber has a very strong tensile strength and the honeycomb keeps it from bending. We all know how this 90% of forces on the surface and 10% of the forces inside theory works. If you look inside the firewall, you can see, the load forces are distributed evenly across all of this. I think the wooden strips are probably just for vibration dampening, and conveniently double for mounting the old style canopy. I think all the calculations being done on these wood strips are not applicable because they are neglecting to add in the support offered by the body design. Regards, Ed Watsonville CA.