X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from [161.88.255.139] (account marv@lancaironline.net) by logan.com (CommuniGate Pro WebUser 5.0.1) with HTTP id 834511 for lml@lancaironline.net; Thu, 17 Nov 2005 16:51:57 -0500 From: "Marvin Kaye" Subject: Re: [LML] Re: Exhaust leak To: lml X-Mailer: CommuniGate Pro WebUser v5.0.1 Date: Thu, 17 Nov 2005 16:51:57 -0500 Message-ID: In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format="flowed" Content-Transfer-Encoding: 8bit Posted for "Chuck Jensen" : Do you know if your cabin is at a negative or positive pressure to the ambient/surrounding air (one way to tell is by opening/closing the alternate air source and watching the altimeter)? Since it happens primarily in climb and slow flight, the plane is at a higher angle of attach and there is less air flow past the cabin, it may be the cabin pressure is slightly negative to the area toward the rear of the plane where your exhaust stream travels past the plane. If the cabin is slightly negative, it'll pull a few of those fumes into the cabin. The dynamics may change at cruise and you have a slight positive pressure in the cabin, hence the traces of the exhaust stream no longer seep into the cabin. If you operate your fresh air vents wide open and don't get a CO alarm, it may be because you are pressurizing the cabin and preventing migration of CO into the cabin and not just diluting and flushing away the in-seepage of CO. That's one advantage of flying a Velocity pusher. All those problems are behind us. Chuck