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In a message dated 2/19/03 8:38:20 PM Eastern Standard Time, 
[EMAIL PROTECTED] writes:

> 
>      "No R.P.M. restrictions are required on any Met-L-Props except for 
those
>      models specified in notes 7, 8, 9, 15, 18, 19, and 20."
>  

This applies to RPM restrictions that originally were imposed on some 
installations.  I'm sure there are some coupes around with a placard on
the 
panel that something like "Avoid continuous operation between 1950 and
2150 
RPM".  These restrictions have since been lifted (In McCauley SB-13, back 
around 1949).  Regardless, the prop TCDS sets limits on which model props
are 
permitted to be installed on which engines and what the dimension limits
are 
for such installations.  Further more, the aircraft TCDS further restricts

the choices and dimensions and takes precedence over the prop TC.  The
prop 
TCDS states that the installation on the 85 horse engine is limited to
2575 
RPM.  They do not specify that they refer to a continental C85, so I
suppose 
there may be another 85 horse engine out there, and it may be certified
for 
more than 2575 RPM.  McCauley is simply stating that that installation
would 
be limited to 2575 RPM.  In reality, however, they are saying that the 
airframe manufacturer should not include that engine/prop combination.

What concerns me is that McCauley has specifically said that when
installing 
the prop on an O200, which operates above 2575, for the purpose of 
maintaining an adequate vibration profile, the MINIMUM diameter is 71".
The 
coupe TCDS stateds that on the C85 installation, the MAXIMUM diameter is
71"  
So, if you have your prop reworked while the O200 crank STC is being 
installed in your C85, and put the two together and decide to fly at
greater 
than 2575 RPM, you are operating in a range that McCauley specifically 
prohibits, as does Continental and ERCO.  You are offically a test pilot
and 
all bets are off.

Why bother anyhow?  If you want to go fast, buy a [real] Mooney.

Over and out, as the uninformed say,
John
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