The AG2x airfoils are intended to be used on composite versions of the 
Bubble Dancer and the Allegro-Lite.  They have very similar lift 
characteristics to the AG3x airfoils.  The main advantage of the AG2x 
is their thinner trailing edges, which reduces foam core volume and weight,
especially at the tips where weight is critical.  The thinner TE's also 
*slightly* improve the max L/D, but the difference is probably within 
variations from manufacturing tolerances.  Finally, the faceted upper 
surface of the AG3x airfoils is superfluous with composite construction.
The AG2x airfoils are smooth.

The direct substitutions are:

AG35 -> AG24
AG36 -> AG25
AG37 -> AG26
AG38 -> AG27


Note:  The AG2x airfoils are considerably thicker and more cambered 
than the AG1x airfoils of the original composite Allegro.  The AG2x 
will therefore produce a slightly lower sink rate, but penetration 
capability will be worse.  The AG2x are probably better suited for 
a composite Allegro-E-Lite.

- Mark Drela