X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from rwcrmhc12.comcast.net ([216.148.227.152] verified) by logan.com (CommuniGate Pro SMTP 5.0.9) with ESMTP id 1099043 for flyrotary@lancaironline.net; Wed, 10 May 2006 10:43:17 -0400 Received-SPF: none receiver=logan.com; client-ip=216.148.227.152; envelope-from=rlwhite@comcast.net Received: from Quail (c-68-35-160-229.hsd1.nm.comcast.net[68.35.160.229]) by comcast.net (rwcrmhc12) with SMTP id <20060510144222m12008mtbge>; Wed, 10 May 2006 14:42:32 +0000 Date: Wed, 10 May 2006 08:43:18 -0600 From: Bob White To: "Rotary motors in aircraft" Subject: Re: [FlyRotary] Airworthiness Message-Id: <20060510084318.ca228d26.rlwhite@comcast.net> In-Reply-To: References: X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.3; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Wed, 10 May 2006 07:31:17 -0700 "Al Gietzen" wrote: > Good News: Velocity N755V received FAA airworthiness certification > yesterday. Also survived an intensive 4-hr inspection by a factory > authorized insurance inspector with a small list of minor items to attend > to. > > > > Not So Good News: Main issue now seems to be cooling during ground > operations, particularly oil cooling, and the secondary temporary issue of > mixture reprogramming (again, after software update). With the wing root > cooler in a pusher configuration there is almost no oil cooling when > standing still. So running at significant power to adjust mixture allows > little time to do anything before reaching temp limits. Then, with cowl on, > it takes hours for it to cool down. > > > > My expectation was for enough natural convection cooling on the ground to > handle low power taxi operations. Earlier static running suggested that > there would be sufficient time, but I'm finding that; a) taxi maneuvering > with brake steering takes more power than anticipated, and b) the 3" thick, > 16 fins/in. oil cooler core has almost no natural-convection cooling. Have > no good ideas at the moment how to improve this situation. Haven't gotten > to high speed taxi yet to see if temps stabilize. > > > > Tracy; can you tell me the basics of your water spray system? > > > > The in-cowl coolant rad gets reasonable air flow because of negative > pressure generated by the prop aft of the cowl. > > > > More later, > > > > Al > Congratulations Al. I'm glad to hear you got your paperwork. Can you set up a blower to provide oil cooling until you get your mixture tuned in? Bob W. (Back to the airport for MORE fiberglass work.) -- http://www.bob-white.com N93BD - Rotary Powered BD-4 (first engine start 1/7/06) Custom Cables for your rotary installation - http://www.roblinphoto.com/shop/