Lancairs - at least the early ones - used an NLF0125 natural laminar flow
airfoil.
It was found that this airfoil and others like it didn't achieve minimum cruise
drag
until the flaps were reflexed. If you talk to a good airfoil designer, they
will
tell you
that a properly chosen airfoil shouldn't need to be reflexed in cruise; if it
does,
the
airfoil has too much camber and requires too much tail downforce, which
increases
drag.
Since then (1985), airfoil designers have been able to achieve as much drag
reduction
as the NLF series with less problematic profiles.
Given that the Europa airfoil is a optimized custom design, I would suspect
that
reflexing the flaps wouldn't improve matters.
Shaun
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