Return-Path: Received: from mv-relay-1.splasers.com ([65.119.109.133] verified) by logan.com (CommuniGate Pro SMTP 4.2b5) with ESMTP id 164337 for flyrotary@lancaironline.net; Wed, 16 Jun 2004 01:44:00 -0400 Received: from usmtv-mx01.spectra-physics.com ([10.209.9.220]) by mv-relay-1.splasers.com (8.11.6/8.11.6) with ESMTP id i5G5hV017620 for ; Tue, 15 Jun 2004 22:43:31 -0700 Received: by usmtv-mx01.spectra-physics.com with Internet Mail Service (5.5.2653.19) id ; Tue, 15 Jun 2004 22:43:31 -0700 Message-ID: <5FA49D34561C5945BA9258B31BF64880DB844C@usmtv-mx01.spectra-physics.com> From: "Wynn, Mike" To: flyrotary@lancaironline.net Subject: Cooling airflow Date: Tue, 15 Jun 2004 22:43:24 -0700 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2653.19) Content-Type: text/plain; charset="iso-8859-1" Dear All, I have been reading with interest for a long time and wanted to ask what maybe a dumb question... Everywhere I have looked people use the standard `Lyc.' type cowls with cheek openings and place the A/C `radiators' either side of the PSRU behind suitable ducts. I assume this is because it is easier to adapt the existing rather than to build a new cowl. However, would it not allow a straighter and less draggy cooling setup if one were to design a cowl with a single opening under the prop (a bit like, but much smaller than, a P40) and then use a single duct to expand the area into the rads (placed under the engine), and then continue straight out under the cockpit - perhaps with some augmented airflow from the exhaust??? Surely this would allow a more efficient airflow and enable smaller intake area and avoid the air having to fight its way round the engine bay to get out? Is it just the fiberglass work people are avoiding, is it the avoidance of the unknown (surely Rusty will have a go here???) What am I missing? Thanks Mike