If you know or even care:
In general, LNC2's as originally designed seemed to better tolerate a CG at
the forward edge of the envelope rather than flight at or towards the
rear. This includes adequate elevator control at flare during
landing. Lancair tested the long engine mount on an LNC2 that moved
the forward CG edge +1.5" and there were no flight problems.
Hmmmmmm.........
Consider that the LNC2 wing has a dramatic change in pitch forces when
the flap is moved between its designed standard position and into -7 degrees
reflex. In my airplane at around 140-160 KIAS the difference in those
two flap positions is approximately a measured 6 degrees in attitude
(couldn't measure the AOA delta). It is clear that moving the flaps
sightly out of reflex (1 or 2 degrees) can help resolve uncomfortable flight at
rear CG conditions by pitching the nose down some and altering the AOA.
Perhaps the rear CG and small tail at cruise leads to some flight instability
that cannot be overcome by the size of the tail?
So, here is the question: If the CG range was calculated for the
normal state of the wing (flaps not in reflex), is it possible that the range is
too far back for normal cruise flight with the flaps in full reflex?
If so, should the POH aircraft data include two ranges based on these
two flap positions? What does such a change do to the forward CG
limit?
Of course, this might raise the same question with the 200 series
aircraft. Why? Well, the faired in position of the flaps for 200
series aircraft is the not-in-reflex position while the plane cruises with the
flaps reflexed and not faired in. The 300 series aircraft has the flaps in
reflex when they are faired in to the
fuselage.
When considering an answer, remember that wings designed to operate by
changing shape (TE goes through some reflex angles) have been primarily used in
tailless airplanes and the TE position controls the pitch balance of the
airplane. I have no idea how the CG range for such an aircraft is
determined.
Your humble servant,
Grayhawk