X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmmtao102.cox.net ([68.230.241.44] verified) by logan.com (CommuniGate Pro SMTP 5.1.12) with ESMTP id 2394281 for flyrotary@lancaironline.net; Thu, 18 Oct 2007 15:32:51 -0400 Received-SPF: none receiver=logan.com; client-ip=68.230.241.44; envelope-from=steve@stevet.net Received: from fed1rmimpo02.cox.net ([70.169.32.72]) by fed1rmmtao102.cox.net (InterMail vM.7.08.02.01 201-2186-121-102-20070209) with ESMTP id <20071018193137.PEOG15207.fed1rmmtao102.cox.net@fed1rmimpo02.cox.net> for ; Thu, 18 Oct 2007 15:31:37 -0400 Received: from [192.168.2.203] ([68.6.58.190]) by fed1rmimpo02.cox.net with bizsmtp id 1vXc1Y00746FLUs0000000; Thu, 18 Oct 2007 15:31:36 -0400 Mime-Version: 1.0 (Apple Message framework v752.2) In-Reply-To: References: Content-Type: text/plain; charset=US-ASCII; format=flowed Message-Id: <513E5407-266F-4F41-A424-BDF88BAE0B88@stevet.net> Content-Transfer-Encoding: 7bit From: Steve Thomas Subject: Re: [FlyRotary] Re: Math Help Date: Thu, 18 Oct 2007 12:31:35 -0700 To: "Rotary motors in aircraft" X-Mailer: Apple Mail (2.752.2) Perfect! Thanks so much, Ron. Best Regards, Steve ____________________________________________________________________ On Oct 18, 2007, at 12:07 PM, Ron Springer wrote: > Steve, > > For a flat plate 90 deg to the flow, the drag > coefficient is about 1.17. The drag is equal to the > drag coeff. times the plate area time the dynamic > pressure. For a fixed true airspeed of 200 mph, the > dynamic pressure varies with altitude. It is 0.71 psi > at sea level and 0.52 psi at 10,000 ft. > > So, the drag force is 12.5 lbs at sea level and 9.2 > lbs at 10,000 ft. Hope that helps. > > Ron > >