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Here is an image showing the windward and leeward sides of the Moth Wing when sailing. We left the spreaders off for the testing. This resulted the mast deflecting a bit to windward in the panel below the hounds, which is not desirable. So we either need to stiffen the mast or put the spreaders on (or both). However, apart from a few wrinkles which we can tune out, the section shapes were good. Windward telltails are streaming and a couple near the luff are actually going forward - indicating the stagnation point is aft of the luff pocket in the mid section. This would suggest about a 12 degree angle of attack. All the leach telltails are streaming so there is still good attachment on the leeward side. On the leeward image, the telltails are all streaming nicely. The leach telltails at the top of the wing are just angling to leeward a bit. This may indicate a little more twist is warranted, though this is still along way from stalling. From our modelling this pattern would suggest that the top of the sail is at about 13-14 degrees AoA.  See Image below for an approximation of the test configuration.