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Date: Tue, 25 Apr 2006 09:18:59 -0400
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From: Walter Atkinson <walter@advancedpilot.com>
Subject: Re: [LML] P&W CHT


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One should keep in mind that those are very low compression engines=20
(6:1) which operate under relatively low ICPs.  I work very hard to=20
keep my own personal P&W engines on my Twin Beech under 380.  Prior to=20=

doing that I replaced five cylinders in the first 200 hours of=20
operation.  After adhering to the lower CHT, I have not replaced a=20
single cylinder in the last 800+ hours.  I realize that anecdotal=20
evidence is a poor substitute for hard data, but it is in harmony with=20=

the hard data.  Those high CHTs are a result of poor cooling baffle=20
design.  I have worked diligently to improve them with moderate=20
success.

Walter


On Apr 24, 2006, at 11:43 PM, Paul Lipps wrote:

My airline pilot friend, who is building a Lionheart, told me what the=20=

CHTs were=A0on the P&Ws he flew on the twin-engine Convair. Max CHT,=20
260C, 500F. METO, 232C, 450F. RECOMMENDED cruise, 204C, 400F. This was=20=

the temperature that they were supposed to adjust their cowl flaps to=20
achieve during cruise! BTW, I was asked, on my first posting about CHT,=20=

to reference=A0the source of my opinions, which I subsequently did. I=20
hope all that respond with other views=A0will do likewise.=

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One should keep in mind that those are very low compression engines
(6:1) which operate under relatively low ICPs.  I work very hard to
keep my own personal P&W engines on my Twin Beech under 380.  Prior to
doing that I replaced five cylinders in the first 200 hours of
operation.  After adhering to the lower CHT, I have not replaced a
single cylinder in the last 800+ hours.  I realize that anecdotal
evidence is a poor substitute for hard data, but it is in harmony with
the hard data.  Those high CHTs are a result of poor cooling baffle
design.  I have worked diligently to improve them with moderate
success.


Walter


On Apr 24, 2006, at 11:43 PM, Paul Lipps wrote:


<fontfamily><param>Arial</param>My airline pilot friend, who is
building a Lionheart, told me what the CHTs were=A0on the P&Ws he flew
on the twin-engine Convair. Max CHT, 260C, 500F. METO, 232C, 450F.
<bold><italic>RECOMMENDED </italic></bold>cruise, 204C, 400F. This was
the temperature that they were supposed to adjust their cowl flaps to
achieve during cruise! BTW, I was asked, on my first posting about
CHT, to reference=A0the source of my opinions, which I subsequently did.
I hope all that respond with other views=A0will do =
likewise.</fontfamily>=

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