Monty Roberts wrote:

Russell,
Please describe the low pressure area which you are referring to.

As the fuselage sides and bottom begin to slope inward, a low pressure area will
be formed.  Your intake scoop appears to be a few inches aft of where the bottom
and sides transition from parallel to inward-sloped.  Thus it appears that the
intake scoop will be in a low pressure area.  If you move the intake a few inches
(6?) forward, you'll be clear of the low pressure area.

The location of the scoop is about the same as the original Rutan design. The
inlet area is a little different.

I'm not an aerodynamicist, so perhaps Burt knows something I don't.  However,
until I hear otherwise, I'm sticking with my opinion that the current scoop's
opening is at the leading edge of a low pressure area.

The reason that I angled the strakes rearward is that it is the same as the
original aircraft. I was trying not to introduce any unforeseen moments in the
pitch axis. I wanted to maintain
the flying qualities of the original design. The strakes do tend to disturb the
airflow into the prop. On the Long EZ Burt seemed to address this by placing the
prop center line and the strake in the same plane, or at least much closer than
the Vari. Granted this is much preferable. Unfortunately, the prop is also
closer to the trailing edge of the wing in the Long EZ. One of the reasons that
I like the Vari is the greater distance between the trailing edge and the prop.
I placed the prop in the same location as the 8 inch prop extension to move it
out of the wing wake as far as possible. The airfoil on the Long is I understand
superior to the Vari. Also the anhedral is unnecessary with ailerons on the
wings. I built this model when I was intending to construct a Vari with a single
rotor engine. Since then I have decided to go with the two rotor and a Long EZ
(I figure Herb Sanders has had experience with both, and he recommends the Long,
so why argue) The main thing I was trying to illustrate with this model is that
the base drag issue can be addressed with a liquid cooled engine without a large
increase in frontal area. Also the use of an ejector type exhaust for ground
cooling and max efficiency.

OK.  I can see value in your keeping the design the same in order to minimize the
number of experiments you commit with the aircraft.  :-)

Russell Kent

 
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