Fast glass biplanes

My take on this is that while it is true that both surfaces on a canard or
tandem wing design are lifitng surfaces, the canard cannot use all of the
available lift from the main wing - if you want the stall protection - and thus
the main wing needs to be made much larger than needed for cruising flight if
one is to expect a reasonable landing speed.

In the case of my Quickie the Eppler main wing stalls at a fairly high angle of
attack but it's peak Cl is not that good. The result is that during landing
the canard is doing more than it's share of the work. Some Quickies (all
Quickies are single seat - the 2 seaters are Q-2/200's) land as fast as the
much maligned BD-5.

Another factor to consider is just because the little wing is in the back it
must not necessarily be providing down force. It can also lift and still be
part of a pitch stable plane.


props.. Flat out, the Glasair was faster, but only slightly -- 215
vs. 210
mph.

Even this surprises me, I had been led to understand
that the canard design is inherently more efficient
because the canard wing, besides its basic function
as a stabiliser, also helps to generate lift; wheras
the stabiliser in a conventional design must push down.
So that for every 100 lbs of weight, the main wing in
a conventional design carries 110 lbs, in a canard only 90.