This must be for a power airplane, in which case airfoil choice is not likely to be very critical. The NASA GA airfoils are great for the size, application, and speed range they were designed for - full size General Aviation - but they are not a good choice for models operating well below Re =1M. Why do you want to use that airfoil in particular? There are literally hundreds of airfoils designed for model use since the 1980's that would be a better choice, as well as the real Clark Y, some of the NACA 4 series, etc. I really don't want to go through all that to see data that I'm not sure of. I happened to have a dat file of the LS(1) on hand, so I didn't have to do anything this time. If I need to rearrange airfoil ordinates into a dat or other format, I use Excel to do the data sorts because I have used it for 30 years. Airfoils with nice smooth curves at the appropriate Re will be much easier to fly, and the Clark Y also has considerably better performance as well. They also have a strange stall at lower Re as the bubble moves and collapses, as seen at the sudden decrease and then increase in drag around Cl = 0.9. At lower Re they have poorly controlled laminar separation bubbles as evidenced by the high drag in the "bucket" at moderate Cl. The NASA General Aviation (GA) airfoils were designed for long laminar flow runs for low cruise drag at considerably higher Re than on models. There may be better airfoils for your application than the Clark Y, but it would certainly be better than the LS(1) at model Re. The Clark Y has considerably better performance everywhere, and much better stall characteristics (attached). Since I don't know anything about the model you are planning, I just did a quick Profili (XFoil) run at Re=200k against a Clark Y.
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