The T2C has carbon fiber sprogs and carbon outboard leading edges. These changes lead to other changes. Wills Wing can turn down the carbon fiber sprogs on the T2C four turns compared to the T2 and get the same pitching moment. They in fact ship the T2C with the sprogs turned down two turns. They would appreciate it if you left them there.

Steve Pearson has been working with the sprogs for a number of years going through various permutations of support cable thickness, weight, etc. In testing these sprogs he setup a T2C and a T2 at the factory with the keel and the tips are stands. He placed 40 pound weights on the tips of the outboard sprogs. The T2 with the the aluminum outboard leading edge, aluminum sprogs and lighter cable support deflected 12 inches under this load. The T2C deflected 7 inches with the heavier support cable (the one that comes standard with the T2C).

The deflection is due to a very slight bending in the sprog, stretch in the support cable (about half the deflection), and torsional distortion in the leading edge. Obviously the T2C is better equipped to handle extreme loads on the sprogs which explains its great ability to maintain the same pitching moment with initially lower sprogs.

The torsional loads from the outboard sprogs would normally be transmitted all the way along the leading edges to the nose plate (which would feel significant forces because of the long lever arm). The T2's have a cross bar junction that was designed specifically to stop the transmission of these torsional forces at the junction. Of course, the inboard sprog is at the cross bar/leading edge junction so torsional loads from this sprog are absorbed at the junction also.

Steve Pearson's design philosophy is to build the carbon fiber outboard leading edges as heavy as the aluminum ones but stronger. Other carbon fiber outboard leading edges are thought of as lighter than their aluminum counterparts, and that's a benefit for sure, as it reduces the rotational inertia of the glider.

Steve's outboard leading edges are 20% stiffer in bending and 30% stronger in torsion than the aluminum outboard leading edges that they replace. This increased strength and stiffness has the obvious advantage of allowing for a lower sprog setting. Two different design approaches. Steve Pearson writes:

The bending strength is almost twice that of the 7075 aluminum rear leading edge it replaces--in fact we proof test each carbon rear leading edge to what would be ultimate load on the 7075 spar. Practically, the ultimate strength doesn't have as much significance as the increment in stiffness, it just means that it's very unlikely that it would be the first component to fail but it's nice to have an extra margin of strength and durability in composite parts which are sometimes harder to inspect and more subject to damage.

The hardware on the sprogs have been changed to allow of them to be quickly turned up or down one full turn. You no longer have to fiddle with the hardware next to the leading edge, but just undo a clip at the end of the support cable half way down the sprog.

The new T2's have different sail configurations (than the previous T2's) and in particular the sail mounting hardware at the end of the leading edge. This has been changed and beefed up after Wills saw what happened after Dustin put some wear on the previous version looping the glider.

There is now a tensioning bolt that allows you to easily adjust the sail tension.

In addition there is a new mechanism for adjusting the tips up or down. There is one bolt in the leading edge near the tip. You just rotate the easily accessible bolt and the leading edge is rotated. Much simpler than the previous means of adjustment.

Steve Pearson writes:

The leading edge sail tension can be precisely adjusted with the eye-bolt. The wand receptacle can be adjusted for turns or other tuning parameters by turning the jack-screw at the rear of the assemble rather than twisting the endcap. This adjustment articulates the wand straight up and down rather than on a conical path.