Message-ID: <35F577DA.15E77381@flash.net>
Date: Tue, 08 Sep 1998 13:30:50 -0500
From: Ken Harwood <kenharw@flash.net>
To: John Cooper <heyduke@digital.net>, Lancair List <lancair.list@olsusa.com>
Subject: RE: MT Prop
Mime-Version: 1.0

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John, 

I have been running my Lancair 360 with the 200 HP+ engine and the
3-bladed MT12B prop for over 6 years now and have had very little
problem with it.  Once, when running the Sun 100 race I had the prop go
to 3500 rpm due to  cavitation of the prop governor due to oil getting
too hot and foaming up in the governor.  This was not a problem with the
prop itself.  Because of this over speed of more that 25 percent I had
the prop disassembled and checked.  There was no damage.  Since that
time [over 5 years] the propellor has had no internal maintenance.  The
ability to withstand that kind of overspeed is a pretty good indication
that the prop is tough.  I have checked with the manufacturer and found
that the prop should go 1500 to 2000 hours before maintenance is
required.  Once in awhile, if the plane hasn't been flown for quite some
time during the winter I will get a trace of grease escape from the hub
of the prop.  I have heard that this is normal.  The prop now has 550
hours on it.  

I believe the MT prop is a good choice for the Lancair due to the
tremendous speed range the plane is capable of.  You don't have to worry
about harmonics between the engine and the prop as you do with all metal
props.  

Ken Harwood
N15KH