> It's a beautiful aircraft, a striking compromise between conventional
> and canard planforms. I wonder what the stall characteristics are like?
> With the canard it's almost impossible to stall as the nose drops on the
> approach to a stall.
Technically speaking, it isn't a true "canard" design, but is a
lifting surface with no pitch controls. The aircraft has a traditional
T-tail. The other aspect of the aircraft, which is unusual, is that
the fuselage is a "lifting body". So, you have three lifting surfaces.
The tail itself is not a lifting surface, but is neutral. Nearly every
jet and turboprop aircraft has a flying tail with negative lift, which
translates to drag. But the flying tail of a standard aircraft is
typically designed to stall before the main wing which translates to a
slight pitch down or a reduced effectiveness of pitch control. Because
of all this, the Avanti flies nearly identically to any other
conventional turboprop with the exception that the actual stall
characteristics are a bit more mushy without a direct break.
"Common Wisdom" and Wikipedia say that the Avanti has a flying tail
that is used as part of the lift of the aircraft, but this is not
true. The tail surfaces are nearly neutral. As proof, the Avanti is
designed to use very little trim adjustment. Of course, most aircraft
in this class don't trim the control surface, but actually change the
entire angle of the horizontal "surface" so the elevators can stay in
a neutral position.
As is typical with most "canard" or dual-wing aircraft designs, there
has a been design alterations required to correct for all-weather and
icing conditions use. It seems like every designer wants to use a
laminar flow wing for the canard, but fly an approach in heavy rain or
icing conditions and the aircraft becomes a lawn dart. I believe that
the Avanti uses laminar flow for the main wing, but has a more
conventional wing design for the forward wing.
I'm sure Jim can weigh in an the aerodynamics stuff.
AG
AG
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