Subject: Alternative Powerplant
From: Rotary Engine
Date: 11/9/2008, 8:53 AM
To: AAA Put this in the To box



   Has anyone heard of an experimental aircraft using a japanese
   4-cylinder motorcycle engine? The advantages seem obvious when
   compared to other non-rotary auto conversion choices. Modern 1000cc
   engines make 180hp, are liquid-cooled, lightweight, and inexpensive.
   If such an engine was de-tuned to 100-120hp by lowering the redline
   (say from 13k to 9-10k), it might give close to a 1:1 power:weight
   ratio with high reliability.

   I can't be the first person to think of this. If it hasn't been done
   before, why?

   -Chris Wood

   Probably a cooling issue. Motor cycle engines, like car engines, are
   light duty. Several people have tried air cooled BMW engines for the
   past twenty
   years but they never caught on.

   http://www.kawasaki.com/Products/product-specifications.aspx?id=345
   Engine Type Four-stroke, liquid-cooled, DOHC, four valve per cylinder,
   inline-four with VVT
   Displacement 1,352 cc

   Maximum Torque 100.3 LbFt @ 6,200 rpm
   Compression Ratio 10.7:1

   Curb Weight 670.3 lbs. 679.1 lbs. (ABS model)

   ------------------------------------------------------

   No mention is made of the red line or the HP surprisingly.
   At 670 pounds for the whole bike the engine block could easily
   weigh 200 pounds or more.

   100 ft pounds of torque at 6200 RPM is 119 HP. About the same power
   to weight
   ratio as a Continental O-200 direct drive aircraft engine. Of course
   you will
   still need a 20 to 30 pound gear box. Motor cycles are designed for
   side ways
   mounting... chain drive so it is no easy matter to design a gear box
   that will
   take the power out inline or turn the drive 90 degrees for a propeller.

   That is also half the displacement of a Mazda 13B rotary engine with
   about the
   same block weight but the rotary will easily put out 200 HP in side
   port form
   and 250 HP in p-port form.

   These engines in new shape are also not cheap.

   Paul Lamar

   I've heard of one.  They are running a Yamaha R-series liquid cooled
   engine rated at 150 hp.  It uses a reduction gear and a drive shaft
   to a ducted fan.  So far, I've only seen graphics on the test rig.
   This is a multi-year development program by a University, so things
   tend to progress in short spurts.  Haven't heard any feed back.
   This engine is also used in the Yamaha 4-stroke PWC's.  From one
   graphic it's clear they are giving a lot of thought to the cooling
   system with a separate plenum pumped by the discharge from the fan.
   This program has been funded by the Light Aircraft Industry
   organization of the country via the government.  You suspect in
   small yearly grants.  The monitors for the program are pretty well
   known engineering types.

   George W

Well George as you well know a ducted fan and drive shaft is not the greatest for a 200 MPH airplane :) Perhaps they have been taken in by Mark Moore.

http://www.rotaryeng.net/PAV.html

What country and what University?

Paul Lamar

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