X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Sat, 03 Nov 2007 22:05:00 -0400 Message-ID: X-Original-Return-Path: Received: from elasmtp-kukur.atl.sa.earthlink.net ([209.86.89.65] verified) by logan.com (CommuniGate Pro SMTP 5.2c1) with ESMTP id 2454352 for lml@lancaironline.net; Sat, 03 Nov 2007 20:18:38 -0400 Received-SPF: neutral receiver=logan.com; client-ip=209.86.89.65; envelope-from=mnewman@dragonnorth.com Received: from [70.91.142.49] (helo=PCmike2) by elasmtp-kukur.atl.sa.earthlink.net with asmtp (Exim 4.34) id 1IoTBe-0004ti-Sn; Sat, 03 Nov 2007 20:17:59 -0400 From: "Michael Newman" X-Original-To: "'Jeffrey Liegner, MD'" X-Original-Cc: "'Lancair Mailing List'" References: Subject: RE: Speeds at Altitude X-Original-Date: Sat, 3 Nov 2007 20:18:43 -0400 Organization: Dragonnorth Group X-Original-Message-ID: <098401c81e78$429f15d0$0601a8c0@sentira.net> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0985_01C81E56.BB8D75D0" X-Mailer: Microsoft Office Outlook 11 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 In-Reply-To: Thread-Index: AcgeN7F/kgNXscv5TXWiW/r1f/l2fAAPwU3Q X-ELNK-Trace: 4981850a937e3365551c28c27865cf0a239a348a220c260994a119effc054bf09c2e434fbd6b2d2ea7ce0e8f8d31aa3f350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 70.91.142.49 This is a multi-part message in MIME format. ------=_NextPart_000_0985_01C81E56.BB8D75D0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit My cabin pressure runs about 9K at FL250 about 5 pounds differential. I run LOP this is required to keep the TIT temperatures in reasonable range. It is possible to be very rich of peak at slightly more power but I don't like the range at 20+ GPH (don't fly there and don't have exact numbers). My experience with pressurization was that I had leaks around the door seal. I added some foam for the seal to seat against and the door seals better and I am now able to get 5 pounds. If you can not get 5 pounds I suspect there is a leak. I climb at 30 to 31 inches 2500 rpm to get to FL 250. I manage my airspeed to maintain CHTs at 400 degrees (or less) I can only climb 800 to 1000 fpm continuously at about 160 to 180 kts depending on temperature. I can climb faster for short periods. The power is there, with better engine cooling faster climb at lower airspeeds would be possible. _____ From: Jeffrey Liegner, MD [mailto:liegner@embarqmail.com] Sent: Saturday, November 03, 2007 12:16 PM To: Michael Newman Cc: Lancair Mailing List Subject: Re: Speeds at Altitude What is your pressurization status at this sub-28" MAP and FL250....cabin altitude and PSI differential? I've noticed that my IAS is about the same 188-192 regardless of MAP power setting (30" to 36", 2500 RPM). Obviously, fuel flow is different. And you are LOP with 15.3 gph, which makes the power output here even lower than ROP operations, here at something ~50%. And what are your cruise CLIMB power settings to get to FL250? Thanks. Jeff L I saw 343 Kts groundspeed today. FL 250 2450 rpm 27.5 inches 15.3 gph 270 TAS wing tape installed Lancair IV-P N776CM _____ Michael Newman Dragonnorth Group 319 Dean Rd. Brookline, MA 02445 Cell: 617 821-4608 Home: 617 566-7975 Fax: 617 566-7975 www.dragonnorth.com mnewman@dragonnorth.com -- New email address: liegner@embarqmail.com ------=_NextPart_000_0985_01C81E56.BB8D75D0 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Re: Speeds at Altitude
My cabin pressure runs about 9K at FL250 about 5 pounds = differential. I=20 run LOP this is required to keep the TIT temperatures in reasonable = range. It is=20 possible to be very rich of peak at slightly more power but I don't like = the=20 range at 20+ GPH (don't fly there and don't have exact numbers). My = experience=20 with pressurization was that I had leaks around the door seal. I added = some foam=20 for the seal to seat against and the door seals better and I am now able = to get=20 5 pounds. If you can not get 5 pounds I suspect there is a=20 leak.
 
I=20 climb at 30 to 31 inches 2500 rpm to get to FL 250. I manage my airspeed = to=20 maintain CHTs at 400 degrees (or less) I can only climb 800 to 1000 fpm=20 continuously at about 160 to 180 kts depending on temperature. I can = climb=20 faster for short periods. The power is there, with better engine cooling = faster=20 climb at lower airspeeds would be possible.

From: Jeffrey Liegner, MD=20 [mailto:liegner@embarqmail.com]
Sent: Saturday, November 03, = 2007=20 12:16 PM
To: Michael Newman
Cc: Lancair Mailing=20 List
Subject: Re: Speeds at Altitude

What is your pressurization status at this sub-28" MAP and = FL250....cabin=20 altitude and PSI differential?

I've noticed that my IAS is about the same 188-192 regardless of = MAP power=20 setting (30" to 36", 2500 RPM).  Obviously, fuel flow is = different.

And you are LOP with 15.3 gph, which makes the power output here = even lower=20 than ROP operations, here at something ~50%.

And what are your cruise CLIMB power settings to get to = FL250?

Thanks.

Jeff L


I saw = 343 Kts=20 groundspeed today.
 
FL=20 250
2450=20 rpm
27.5=20 inches
15.3=20 gph
270=20 TAS
wing = tape=20 installed
Lancair = IV-P=20 N776CM
 
Michael Newman
Dragonnorth = Group

319 Dean Rd.
Brookline, MA=20 02445
Cell: 617 = 821-4608
Home: 617=20 566-7975
Fax: 617 566-7975
www.dragonnorth.com
mnewman@dragonnorth.com
 

--
New email address: = liegner@embarqmail.com
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