Paul,
      May be of interest to group.

     Kelly Troyer

--
Dyke Delta/13B Rotary Power

So far, the prop has been the least of my trouble.  At 7300rpm, my prop
turns 2560~ and Launie Prince, Prince Props, says I can go to 8800/3100rpm
before the tip breaks supersonic.  I climb out at 7000, at 120kts, 
+1600 fpm rate.RV6A.  I had originally thought I would get 7500, but not
yet. At 7300 I get 164kts (190mph)at 3000 ft alt.  Temperatures start to
climb after 6500, however, 85F OAT. Perhaps, this fall, I can push the upper
limit.  

Jerry Bass      you can send this to Paul Lamar.


Well Jerry what ARE your thoughts on this subject?
Jim

  Jim and Larry,
      Recent posts from Tracy Crook have indicated that
he has a commercial customer that wants 2.85 drives for
their a/c. If so he will probably produce them. Paul
Lamar of the "ACRE" newsletter has been actively 
promoting the use of the 2.85 drive. He thinks we are
giving up about 20 hp because of prop tip speed 
restrictions with the 2.17 drive. He thinks being able
to turn 7000 rpm+ for takeoff is not a problem.(I agree)
      Talk to Jerry Bass and see what he thinks. The
biggest problem is probably props. Most off the shelve
props are optimized for 2700 rpm. Paul Lamar and others
on the group think this problem can be solved. The three
of us Delta builders with Ivoprops are using an extra 
blades and/or more diameter. We have yet see how the Ivo
fares.

     Kelly

Dyke Delta/13B Rotary Power                    

 
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