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>The Lancair Columbia and the Cirrus SR20 received type certification.

>They are both good, fixed wing aircraft, made out of fiberglass, and

>they are both related to the Stallion.  The wing and tail design for

>the Lancair ES (the aircraft from wich the Columbia was designed)

>came from the Stallion.   On the Columbia however, a new wing airfoil

>was selected by its designer (not me).  This airfoil was not spin resisant

>and as such, cuffs had to be added to the wing tips during certification.

>This is an after thought and would not have happened if Lancair had

>kept the original (Stallion) ES airfoil.  And the Cirrus SR20 is somewhat

>of a copy of the Lancair ES.



I believe the information in Hollman's newsletter is seriously in err.

According to Hollman's own book (Modern Aircraft Design), the Stallion, the

ES, and the IV all use the same airfoil for the wing.  (For the

technically-minded, Hollman reports that the wing root is RXM5-217, the wing

tip is NACA64212, and there is a linear interpolation from root to tip.).  I

spoke with several IV owners and Neico folks at Sun-N-Fun about the stall

characteristics of the IV.  Alll indicated that while the IV is wonderful to

fly, the stall is quite sharp and often involves a wing drop.  Unless I'm

missing something, a wing drop in a straight, coordinated stall is not a

property of a spin-resistant airfoil.  Since the Stallion and ES share the

same airfoil as the IV (albeit with a wider span), it stands to reason that

they are not spin resistant either.  I suspect the folks at Neico knew what

they were doing when they redesigned the wing for the Columbia.  If anyone

has any other information about this, I'd be interested.