I wondered how long I could go biting my tongue. and since I was sort of
invited in
I will give my call on this argument. The EZ's and their variations are very
fine
aircraft, but a canard does not represent the optimum cure all airframe by
any
means. I thnk it was almost 15 years ago that I made the statement that you
will probably never see Mr Rutan ever use a canard as the primary pitch
control again, and I think that pronouncement has held true. With a canard,
you must never never work the main wing to it's maximum capability, because
if the canard does not stall first you will lose control of the aicraft. The
limited pitch authority of this configuration generally will prevent the
classic stall spin situation, but that did not come free. This is even more
pronounced
with the Tandem configurations, if you are too slow, low, you cannot flare.
Putting flaps on a canard usually involves variable geometry canards or
other
aerodynamic tricks. I also do not believe that three surface is the best of
both
worlds, more like the reverse of that, A typical three surface configuration
is
primarily a conventional configuration, with the added front surface moving
the center of lift so you can move the main spar out of the cabin.
Aerodynamically
it is much like a very extreme reverse stagger unequal biplane.

With the exception of the Voyager, no canard has set any major speed or
efficiency record in any class,. Sailplanes are a strong test of efficiency,
and the canard sailplane was not a good call.
Vance

That latter statement is not true. I don't have all the details, but
Dick Rutan set many records in his Long-EZ in the early days.
Jim Price set a couple altitude records with his plane, over 30,000 feet
with a normally aspirated airplane. Canards also won some of the early
CAFE efficiency awards. Many of these awards have probably been
superceded by now, but I bet some of them still stand.

The Long-EZ is a dream machine to fly. I don't care if it's not the
aerodynamic ideal!

Perry

You will admit Perry, it is not exactly a short runway airplane.
As I recall you used to plan your long cross countries around 
runway lengths :) Klause is building a short wing Long EZ so we
shall see how he does at 2500 foot SZP.

Paul Lamar
 
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