X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fmailhost01.isp.att.net ([204.127.217.101] verified) by logan.com (CommuniGate Pro SMTP 5.2.16) with ESMTP id 3883301 for flyrotary@lancaironline.net; Mon, 12 Oct 2009 12:38:32 -0400 Received-SPF: none receiver=logan.com; client-ip=204.127.217.101; envelope-from=bbradburry@bellsouth.net Received: from desktop (adsl-157-211-223.mco.bellsouth.net[70.157.211.223]) by isp.att.net (frfwmhc01) with SMTP id <20091012163758H0100jm03de>; Mon, 12 Oct 2009 16:37:58 +0000 X-Originating-IP: [70.157.211.223] From: "Bill Bradburry" To: "'Rotary motors in aircraft'" References: In-Reply-To: Subject: RE: [FlyRotary] Re: where's the missing power? Date: Mon, 12 Oct 2009 12:38:08 -0400 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0019_01CA4B38.DAAD1B30" X-Mailer: Microsoft Office Outlook 11 Thread-index: AcpK/XQwooMENI+0TfmipnNOospeIAAXEVNA X-MimeOLE: Produced By Microsoft MimeOLE V6.0.6002.18005 This is a multi-part message in MIME format. ------=_NextPart_000_0019_01CA4B38.DAAD1B30 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Al, That is true. But if you set the altimeter to your field elevation, you can read the barometric pressure in the Kollsman window. The reported baro pressure is at ground level, so this will not work at altitude. Only when you are on the ground. Also at 18K feet and above, the Kollsman window is always set at 29.92. Bill _____ From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen Sent: Monday, October 12, 2009 2:33 AM To: Rotary motors in aircraft Subject: [FlyRotary] Re: where's the missing power? I think your manifold pressure at full stop should read the same as your altimeter if it is set to the field elevation. Bill Bill; No. The altimeter setting is the air pressure at sea level - for whatever the conditions are at your elevation. If you are flying at 18000 ft, surely the air pressure would not be 29.92. Al ------=_NextPart_000_0019_01CA4B38.DAAD1B30 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable

Al,

That is true. But if you set the altimeter to your field elevation, you can read the barometric pressure in the Kollsman window. The reported baro pressure is at ground level, so this = will not work at altitude. Only when you are on the = ground.

Also at 18K feet and above, the Kollsman window is always set at = 29.92.

Bill

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen
Sent: Monday, October 12, = 2009 2:33 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: = where's the missing power?

I think your manifold pressure at full stop = should read the same as your altimeter if it is set to the field = elevation.

Bill

Bill;
=
No. The altimeter setting = is the air pressure at sea level – for whatever the conditions are at = your elevation. If you are flying at 18000 ft, surely the air pressure = would not be 29.92.

Al

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