Return-Path: Received: from smtphub0.shell.com ([134.163.253.248]) by ns1.olsusa.com (Post.Office MTA v3.5.3 release 223 ID# 0-64832U3500L350S0V35) with ESMTP id com for ; Thu, 4 May 2000 09:56:50 -0400 Received: from icbmsxh1.newcos.com (icbmsxh1.shell.com [138.58.22.22]) by smtphub0.shell.com (8.8.8+Sun/8.8.8) with ESMTP id JAA17205 for ; Thu, 4 May 2000 09:02:40 -0500 (CDT) Received: by ICBMSXH1 with Internet Mail Service (5.5.2448.0) id ; Thu, 4 May 2000 09:02:40 -0500 Message-ID: <4F7B567978D9D1118C9B00805FA7BB3E047EA52D@ICBMSX01> From: "Fullinwider RR (Ranson)" To: "'lancair.list@olsusa.com'" Subject: NACA submerged inlet Date: Thu, 4 May 2000 08:51:15 -0500 X-Mailing-List: lancair.list@olsusa.com Mime-Version: 1.0 <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> Concerning inlets. Marv has on his website under 'Scoops & Ducts' three NACA research papers from 1945, 1948, and 1951. These papers indicate, from empirical testing, that the most important part of the duct or inlet is the lip at the rear of the inlet. It's airfoil shape is critical. The 1951 paper also points out that there needs to be a slight bump on the upper and lower edges to prevent the flow from leaving the aircraft surface and forming two vortices within the throat of the inlet. I have yet to see any homebuilt add these small ridges along the upper and lower sides. I am toying with the idea of using a pair of inlets on top of the cowling to cool the engine in place of the High Drag Holes on the front. Just a few thoughts. On well, back to work. Ranny Fullinwider Equiva Trading Inc. (713) 277-5234 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML website: http://www.olsusa.com/Users/Mkaye/maillist.html Builders' Bookstore: http://www.buildersbooks.com/lancair Please send your photos and drawings to marvkaye@olsusa.com. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>