X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [66.219.56.248] (HELO qnsi-xch.qnsi.net) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1125003 for flyrotary@lancaironline.net; Tue, 23 May 2006 13:21:52 -0400 Received-SPF: none receiver=logan.com; client-ip=66.219.56.248; envelope-from=bhughes@qnsi.net Content-class: urn:content-classes:message Return-Receipt-To: "Bobby J. Hughes" MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Subject: RE: [FlyRotary] Re: Pusher cooling .. For John Disposition-Notification-To: "Bobby J. Hughes" X-MimeOLE: Produced By Microsoft Exchange V6.5.6944.0 Date: Tue, 23 May 2006 12:23:33 -0500 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [FlyRotary] Re: Pusher cooling .. For John Thread-Index: AcZ0pyvRZ9k/90b3QDeAuwBa7NkmigJ5jSCw From: "Bobby J. Hughes" To: "Rotary motors in aircraft" John, Is the 6" tube the only air exit from your cowl? Bobby -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of John Slade Sent: Wednesday, May 10, 2006 9:58 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Pusher cooling > they are used in the augmentor tube to suck and expel the hot air from under the cowling. I think Buly's right. Exhaust augmentation has a big effect on ground cooling. I have the exhaust letting out into a 6 inch stainless tube which exits the cowl at the rear. The exhaust pipe stops about 2 inches short of the end of the tube. All the air expelled has to come through the NACA, into a plenum, then through the coolers. I had a fan installed, but it didn't any measurable difference (probably because it was just circulating air) so I removed it. Without the fan my engine stabilizes at about 195F during prolonged taxiing on a 90F day. As long as I save any significant use of power until the run-up right before take-off, I can taxi for as long as I have fuel. John -- Homepage: http://www.flyrotary.com/ Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/