X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from elasmtp-galgo.atl.sa.earthlink.net ([209.86.89.61] verified) by logan.com (CommuniGate Pro SMTP 6.0.9e) with ESMTP id 7090867 for lml@lancaironline.net; Tue, 12 Aug 2014 12:41:56 -0400 Received-SPF: none receiver=logan.com; client-ip=209.86.89.61; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=SjIp7yzbKF9Ns9nljqJOFx+SHy9rV8H6XNprcjwqtSzkFNhXp2G9XmCSn/njTjff; h=Received:From:Mime-Version:Content-Type:Subject:Date:In-Reply-To:To:References:Message-Id:X-Mailer:X-ELNK-Trace:X-Originating-IP; Received: from [71.181.111.109] (helo=[192.168.1.24]) by elasmtp-galgo.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1XHF8S-0006O2-3T for lml@lancaironline.net; Tue, 12 Aug 2014 12:41:22 -0400 From: Colyn Case Mime-Version: 1.0 (Apple Message framework v1085) Content-Type: multipart/alternative; boundary=Apple-Mail-177-57747607 Subject: Re: [LML] Re: Fwd: John Deakin on climbing with a tsio-550 Date: Tue, 12 Aug 2014 12:41:17 -0400 In-Reply-To: To: "Lancair Mailing List" References: Message-Id: <3415AF2B-4E97-4C1D-8B21-34E979303A10@earthlink.net> X-Mailer: Apple Mail (2.1085) X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da940a5d2a8428177d9135a7893d57c80e34e350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 71.181.111.109 --Apple-Mail-177-57747607 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 I had to size them down a bit to get by Marv but if you double click = them you should be able to view them in a pre-viewer and get them to a = legible size. On Aug 12, 2014, at 9:25 AM, Bill Bradburry wrote: Those landmark charts are not really legible. Can they be blown up for = better understanding? Can they be found somewhere with an explanation attached? =20 From: Lancair Mailing List [mailto:lml@lancaironline.net] On Behalf Of = Colyn Case Sent: Monday, August 11, 2014 2:13 PM To: Lancair Mailing List Subject: [LML] Fwd: John Deakin on climbing with a tsio-550 =20 =20 fyi - I put the question to John. Here's what I got back. =20 Begin forwarded message: =20 From: John Deakin Date: August 11, 2014 2:33:16 PM EDT To: Colyn Case at earthlink Subject: Re: climb with a tsio-550 =20 Are you still answering aps questions? =20 You bet! =20 =20 > With a tsio-550 you have these interactions: > - decreasing rpm moves theta-pp back toward TDC > - decreasing MP if mixture were constant moves theta-pp away from TDC > - decreasing throttle from max reduces mixture > =20 > Do you have any idea of the magnitudes of these effects? =20 For magnitude, I can only refer to the =93Landmarks=94 chart (see = below). It doesn=92t directly address your question, though. =20 We=92ve long suggested 200 RPM off takeoff power for noise reduction. = It=92s not exactly good for the engine, but it won=92t do any harm. = Better chance of harm of the TSIOs and TIOs, but still pretty benign. =20 Then George did some noise certification work for the FAA, which = involved heavy instrumentation of the Ada airport and surroundings. He = got a lot of interesting data! One item was with only 100 RPM off the = top end you get 90% of the noise reduction you get with 200 off! =20 So full takeoff power from LIMITATIONs, reduced by 100 RPM for noise. = Very, very minor effect. Now, if you=92re talking big radials at 60=94 = MP, and often operating in detonation, that=92s another story! =20 =20 > It is also commonly thought that reducing MP to 31 inches and rpm to = 2500 is easier on the engine. > So far as I can tell, this is NOT true. =20 You are correct! NOT true. Full power to cruise altitude, UNLESS there = is a time limit on full power IN LIMITATIONS. =20 Best... John Deakin jdeakin@advancedpilot.com www.advancedpilot.com Next LIVE seminar in Ada OK, 10/24/2014 =20 =20 --Apple-Mail-177-57747607 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 I had = to size them down a bit to get by Marv but if you double click them you = should be able to view them in a pre-viewer and get them to a legible = size.

On Aug 12, 2014, at 9:25 AM, Bill Bradburry = wrote:

=

Those landmark charts are not = really legible.  Can they be blown up for better = understanding?

Can they be found somewhere with an explanation attached?

 

From: Lancair Mailing List = [mailto:lml@lancaironline.net] On = Behalf Of Colyn Case
Sent: Monday, August 11, = 2014 2:13 PM
To: Lancair Mailing List
Subject: [LML] Fwd: John = Deakin on climbing with a tsio-550

 

 

fyi - I put the question to John.  Here's what I got = back.

 

Begin forwarded message:

 

From: John Deakin <jdeakin@advancedpilot.com>= ;

Date: August 11, 2014 2:33:16 PM EDT

To: Colyn Case at earthlink <colyncase@earthlink.net>

Subject: Re: climb with a = tsio-550

 

Are you still answering aps = questions?

 

You bet!  <grin>

 

 

With a tsio-550 you have these = interactions:

- decreasing rpm moves theta-pp back toward = TDC

- decreasing MP if mixture = were constant moves theta-pp away from = TDC

- decreasing throttle from max reduces = mixture

 

Do you have any idea of the magnitudes of these = effects?

 

For magnitude, I can only refer to the =93Landmarks=94 chart (see below).  It doesn=92t directly address your question, = though.

 

We=92ve long suggested 200 RPM off takeoff power for noise reduction.  It=92s not exactly good for the engine, but it won=92t do any harm.  Better chance of harm of the TSIOs and TIOs, but = still pretty benign.

 

Then George did some noise certification work for the FAA, which involved heavy instrumentation of the Ada airport and surroundings.  He got a lot of interesting data! =  One item was with only 100 RPM off the top end you get 90% of the noise = reduction you get with 200 off!

 

So full takeoff power from LIMITATIONs, reduced by 100 RPM for = noise.  Very, very minor effect.  Now, if you=92re talking big = radials at 60=94 MP, and often operating in detonation, that=92s another = story!

 

 

It is also commonly thought that reducing MP to 31 inches and = rpm to 2500 is easier on the engine.

So far as I can tell, this is NOT = true.

 

You are correct!  NOT true.  Full power to cruise = altitude, UNLESS there is a time limit on full power IN = LIMITATIONS.

 

Best...

Next LIVE seminar in Ada OK, 10/24/2014

 

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=

= = --Apple-Mail-177-57747607--